Devided into two parts.
WHEREIN IS TAUGHT
the three kindes of Sayling, Horizontal,
Paradoxal, and Sayling upon
a Great Circle
Also an Horizontle Tyde-Table for the
easie finding of the Ebbing and Flowing of the
Tydes, with a Regiment newly Calculated for the
finding of the Declination of the Sun, and many
other most necessary Rules and Instruments
not hereforte set by any.
Newly Corrected and ammended, and the
Eigth time printed
Printed by Gartrude Dawson, living in Bartholomews Close,
the second door from the Half Moon Tavern's Alley
that goes into Alderfgast-street, 1657.
To the right honorable Lord, Charles
Haward, Baron of Effingham, Knight of the noble
Order of the Garter, Lieutenant of her najesties Conties of
Suffix and Surrey, Constable of her Majesties Honour and Castle of
Winsor, Lord high Admiral of England, Ireland, and Wales, and
of the Dominions and fifes of the fame, of the Town of Callis
and Marches thereof, Normandy, Gal oxy, and Greyves, Captain General of
her Jajesties Seas and Navie Royal, and one of her Majesties most
Honourable privie Council, John Davis witheth encrease
of Honour and perfect felicity.
ceive favourable place in the Honourable opinion of Nobility, by so
ight Hounourable, and my special good
Lord as by the instinct of nature, all men
are desirious of knowledge, and take plea-
sure in the varieties of understanding, so
it is lidewise ingrated by the same bene-
fit of nature, in the hearts of true Nobili-
ty, not only to excel the vulgar fort, but
also to cherish, support, and countenance
all such as shall in due course prosecute
their vocation; and as such practices ei-
ther speculative or mechanical, shall re-
much the more shall the practice be estemed: which is the cause
at this time wmvoulswnwrh mw ro pewawnr unro your most Honor-
able favor this finall Treatise of Navigation, being a brief collection
of such practices as in my several voyages I have from experience col-
ected. Among which in three several attempts for the discovery of
the Northwest passage, thereby to find a short and Navigable course
into the rech and fameous Countries of Cathyo China, Pegu, the isles
Molucan and Phillipins, that thereby to the great and inestimable
benefit of our Country, there might be a rich and plentiful trade pro-
cured between us and the said Nations, in short time to be performed,
and with great sefety in regard to the courte: which action and dis-
covery (by means of that honorable Counseller, Sir Frances Wal-
fingham, Knight, Principal Secretary to her Majesty) was with a
good resolution accepted by the Merchants of London, but in the
The Epistle Dedicatory
decay of his honourable life, the attempt was lidewise equaled: but
however mens minds alter, yet undoubtedly there is passage Na-
vigable, and easie to be performed by that course (whensorever it shall
please God to reveal the same) by invincible reasons ad sufficient
experience to be proved: and although before I entred into that dif-
covery, I was sufficiently perswaded of the certainty thereof, by hi-
storical relation, substantially confirmed, whereof to the Adventures
I made sufficient proof, but especially to my worshipful good friend
Mr. William Sanderson, the only Merchant that to his great charges,
with most constant travel, did labour for the finishing thereof: yet I
thank God that of late it hath been my very good chance, to receive
better assurance than ever before of the certainty of that passage, and
such was my vehement desire for the performance thereof that where-
by I was only induced to go with M. Candish in his second attempt
for the South Seas, upon his constant promise unto me, that when we
came to Callifornia, I should there have his Pinnace with my own
Bark (which for that purpose went with me to my breat charges) to
search that Northwest discovery upon those back parts of America,
but God hath otherwise disposed our purposes in his divine judge-
ments, for Mr. Candish being half way through the Straits of Magi
lane, and impatient of the tempestuous furiosness of that place, ha-
ving all his Ships and company eith him, returned for Brasil, by the
autority of his command, when with a leaking wind we might have
passed the same, and returning more than 80 leagues toward Brasil,
my self being in his SHip named the Desire without Boat, Oares, Sails,
Cables, Cordage, Victuals, or health of my Company sufficient for
that attempt, was separated in a freit of weather, and forced to seek
the next shore for my relief, & recovering a Harborow by us named
Port Desire, being in the latitude of 48 degr. did there repair my most
miserable wants, and there staying four months in the most lamentable
distress did again conclude with my Company, to give another at-
tempt to pass the Straits, as my best mean to gain relief. And three
times I was in the South Seas but still by furious weather forced back
again: yet notwithstanding all this my labour to perform the voyage
to his profit, and to save my self (for I did adventure, and my good
friends for my sake, 1100 pounds in the action) Mr. Candish was
content to account me to be the Author of his overthrow, and to
write with his dying hand that I ran from him, when that his own
Ship was returned many months before me.
I am bold to make this Relation to your Lordship, only to sa-
tisfy your Honour of my conversation, for were I faulty of so foul
a crime, I were worthy of ten thousand torments, in presuming to
present this Treatise to your Honourable Lordship, and now refer-
ing my case to your Lordships consideration, I will again return to
In those Northwest voyages, where navigation must be executed
in most exquisite sort, in those attempts I was enforced to search all
possible measn required in sayling, by which occasion I have ga-
theree together this brief Treatise, which with my self I do dedi-
cate to your honourable protection, being disirous of it lay in my
power to do far greater matters in your Loreships service, hoping of
your honorable pardon, because it is only done to shew my ditiful
affection, and not for any singularity that the work containeth, For
I think there be many hundreds in England that can in a far greater
measure and more excellent method express the noble art of Navi-
gation, and I am fully persuaded that our Country is not inferiour
to any for men of rare knowledge, singular explication, and exquisite
execution of the Arts Mathemetick, for what strangers may be com-
pared with Mr. Thomas Digs Esquire, our Country man the great
Master of Archmastryu, and for Theorical Speculations and most
cunning calculation, Mr Dee and Mr. Thomas Heriotts are hardly to
be matched: and for the mechanical practices drawn from the Arts
of Mathematic, our Country doth yield men fo principal escellen-
cy, as Mr Emery Mullenenx for the exquisite making of Globes-
bodies, and Mr. Micholas Hellya for the singularity of portracture,
have the praise of Europe, Mr Baker for his skill and surpassing
grounded knowledge for the building of Ships advantageable to all
purposes, hath not in any Nation his equal.
And now that I may return to the Painful Seaman, it is not un-
known unto all Nations of the Earth, that the English goeth efore
all others in the practices of Sayling, as appeareth by the excellent
discovery of Sir Francis Drake in his passages through the Straits of
Magilane, which being then so rashly known, he could not have
passed, unless he had been a man of great practice asn rare resoluti-
on: so much I may boldly say, because I have seen and tasted the
frowsrdness of the place, with the great unlikelihood of any pas-
sage to be that way.
I might here repeat the most valiant and excellent attempts of Sir
Hugh Willoughbie, Sir John Hawkins, Sir Humphrey Gilbert, and your
Lordships servant, Mr. George Raymond, with divers others that have
given most resolute attempts in the practices of Navigation, as well
for the discovery as other execution, whereby good proof is made,
that not only in the skill of Navigation, but also in the mechanical
execution of the practices of sayling, we are not to be matched by
any Nation of the earth.
And such Navigtion is the mean whereby Countries are discovered
and community drawn between Nation and Nation, the Word of
God published to the blessed recovery of the forreign off c_fts, from
whence it hath pleased his divine Majesty as yet to detain the bright-
ness of his glory: and that by Navigation Common weilles through
mutual trade are not only sufficiently sustained, but mightily enrich-
ed; with how great esteem ought the painful Seaman to be embraced,
by the whole hard adventures sach excellent benefits are achieved, for
by his exceeding great hazards the form of the earth, the quantities
of Countries, the diversity of Nations, and the natures of Zones,
Clumats, Countries and people are apparently made known unto us
Besides, the great benefits mutually interchanged between Nations,
of such fruits, commodities, and artificial practices, where with God
hath blessed each particular country, coast, and Nation, according
to the nature and ldituation of the place.
For what hath made the Spaniard to be so great a Monarch, the
commander of both Indies, to abound in wealth & all natures benefits
but only the painful industry of his subjects in Navigation, their for-
er trade was only figs, oringes, and oyl, but now through Navigati-
on is brought to be gold, silver, pearls, silks, and spice, by long and
painful trade revovered. Which great benefits only by her Majesties
loving clemency and merciful favour he doth possisse: for if her
Highnesse and her most honoragle Lords would not regard the small
distance between her Dominions and those fameous rich Kingdoms,
the ea_nesse of the passage being once discovered (the North west I
mean) with the full sufficiency of her Highnesse subjects to effect the
fame, there could then be no doubt, but her stately seat of London
should be the store house of Europe, and nurse to all Nations, in
yielding all Indian commodities ina far better condition, as a more
easie rate than now brought unto us exchanging commodities of our
own store, with a plentiful return at the first hand, which now by ma-
ny exchanges are brought to us.
Then should the Spaniards again return to his old trade, and our
Sacred Sovereign be seated the Commander of the earth: which trade
and most fortunage discovery, we above all nations ought most prin-
cipally to regard, because of the singularity and invincible force of
our Shipping, which is not the commanding Forttresse of our
Country, but also the dread of our Adversary, and the glory of our
Nation: wherein we do in no sort flatter our selves, fit it was made
apprant to all Nations of the earth, by the late most famous con-
quest that her Majesty had against the huge supposed invincible
Fleet of the Spaniard, being by her Navie under the command o
your Lordship, who there in person and in place of her Majesty, to
your eternal glorious fame did disgrace their glory and confound
their force, and manifest their weakenesse by their dastardly flight,
through Gods providence and your Lordships stately resolution.
Then fith Navigation is a matter of so great moment, I suppose that
every man is bound in duty to give his best furtherace thereunto:
among whom as the most unmeet of all, yet whshing all god to the
painful traveler, I have published this short Treatise, anming it the
Seamans Secrets, because by certain questions demanded and answe-
red, I have not omitted any thing that appertaineth to the secret of
Navigation, whereby if there may grow any encrease of knowledge
or ease in practice, it is the thing which I cheifly desire.
To manifest the necessary conclusions of Navigation in brief and
short terms, is my only intent, and therefore I omit to declare the
causes of trms and difinition of artificial words, as matters superflu-
ous to my purpose, neither have I laid down the cunning conclusi-
ons apt for Schollers to practice upon the shore, but only those things
that are needfully required in a suficient Seaman: beseeching your
honorable Lordship to pardon my boldnesse, and with your favor-
able countenance to regard my dutiful affection, I must humbly com-
mit your good Lordship to the mercies of God, who long preserve
your health, with continual encrease of honour.
From samdrudge by Dartmouth
the 20, of August, 1594.
(Page completely covered with the cosmology of the earth centered Universe)
Your Lordships in all dutiful
service to Command,
(made in a series of 11 concentric circles -- the spheres ?? )
(inside to out Luna, Mercurius, Venus, Sol, Mars, Jupiter, Saturnus,
the Firmamet, Griftalin, The first mouable, Imperiall. )
A very necessary
of the Tydes,
mamed an horizontall
(round instrument for calculating tides)
What is Navigation ?
Navigation is that excellent Art, which demonstrateth by in-
fallible conclusions, how a sufficient Ship may be conducted
the shortest good way from place to place, by Table and
What are these infallible Conclusions ?
Navigation consiseth of three parts, which being well understood
and practiced, are Conclusions infallible, whereby the skilful pil-
ote is void of all doubt to effect the thing purposed, Of which, the first
is the Horizontal Navigation, which manifesteth all the varieties of
the Ships motion within the Horizontle plain superficies, where every
line drawn is supposed a parallel.
The second is a Paradoral or Cosmographical Navigation, which
demonstrateth the true motion of the ship upon any course assigned in
longitude, latitude, and distance, either particular or general, and is the
skilful gathering together of many Horizontal Corses, into one infal-
lible and true motion Paraboral.
The third is a great Circle Navigation, which teacheth bow upon
a great Circle, drawn between any two places assigned (being the only
shortest way between place and place) the Ship may be conducted and
to performed by the skilful application of Horizontal and Paraboral
What is a Corse ?
A Corse is that paraboral line which passeth between place & place,
according to the true Horizontal position of the Magnet, upon
which line the Ship prosecuting her motion, shall be conducted between
the said places.
What is a Travers ?
A travers is the vaiety of alteration of the Ships motion upon the
shift of winds within any Horizontal plain supersicies, by the good
collection of which Traberses, the SHips uniform motion of Corse is
What instruments are necessary for the execution
of this excellent skill ?
The Instruments neccessary for a skilful Seaman, are a Sea Com-
pass, a Cros-staff, a Quadrant, an Astrolaby, a Chart, an In-
strument Magnetical for the finding of the variation of the Compass,
an Horizontal plain Sphere, a Globe, and a Paraboral Compass. By
which instruments, all conclusions and infallible demonstrations,
Hidrographical, Geographical, and Cosmographical, are without
controlement of erroz to be performed: But the Sea Compass, Chart
and Cros-staff, are instruments sufficient for the Seamans use: the
Astrolaby and Quadrant being Instruments very uncertain for Sea-
What is the Sea Compass ?
The Sea Compass, is a principal Instrument in Navigation, re-
presenting and distinguishing the Horizon, so that the Compass
may conveniently be named an Artificial Horizon, because by it are
manifested all the limits and divisions of the Horizon, required to
the perfecture of Navigation, which directions are 32 points of
the Compass, where by the Horizon is divided into 32 equal parts, and
every of those points has his proper name, as in the figure following
appeareth. Also every point of the Compass both contained degrees
minuts, seconds, and Thirds, _c. Which degrees are called de-
grees of azimuth, whereof there are in every point 1 1/4 so that the whol
Compases Horizon containeth 360 degrees of Azimuth, for if if you
multiply 1 1/4 degrees, the degrees that each point containeth by 32 the
points of the compass, it yieldeth 360 the degrees of the Compass.
And of minutes each point containeth 45 being 1/4 of an hour, so that
the whole Compass is hereby divided into 24 hours, by which accompt
there are in an hour 15 degrees, so that every degree containeth 4 mi-
nutes of time, for an hour consisting of 60 minutes hath for his fifteenth
part 4 minutes of time, and in every minute there is _rtyseconds, and
every second contains _rty thirds, either in degrees applies to time
or degrees applied to measure: so that the general content of the Com-
pass is 32 points, 365 degrees, and 24 hours with their minutes,
seconds and thirds.
What is the use of the 32 Points of the Compass ?
The use of the 32 points of the Compass, is to direct the skilful Pi-
lote by Horizontal Travers, how he may conclude the Course or
Paraboral motion of his Ship, thereby with the greater expedtion to
recover the place desired because they divided the Horizon in such limits
as are most apt for Navigation, they do also distinguish the Winds
by their proper Names, for the Wind receiveth his name by that part
of the Horizon from whence it bloweth.
What is the use of 360 degrees of Azumuth ?
By the degrees of Azumuth is known the quantity of the rising and
setting of the Sun, Moon, and Stars, whereby is known the
length of the days and nights in all Climates, and at all times; they
also show a most precise Horizontle dilination of the motion of the
Sun, Moon, and Stars, whereby the certainty of time is measured,
and the vairation of the Compass, with the Poles height, is ingeni-
ously known at all times, and in all places with the help of the Globe.
How is the Hour of the Day known by the Compass ?
It hath been an ancient custome among Mariners, to divide the
Compass into 24 equal parts, or hours, by which they have been used to
distinguish time, supposing an East Sun to 6 of the Clock, a South-
east Sun 9 of the clock, and a South Sun 12 of the clock &c. as in
the figure following shall plainly appear. But this account is very
absurd, for with us in England (the Sun having his greatest North de-
clination) it is somewhat past 7 of the Clock at an East Sun, and at
a Southeast Sun it is past 10 of the Clock: also when the Sun is in
the Equinoctial, the Sun is half the day East, and half the day West,
to all those that be under the same: so that the Sun then, and to those
people useth but 2 points of the Compass to perform the motion of
twelve hours: therefore the difinations of time may not well be given by
the Compass, unless the Sun be upon the Meridian, so that you be far
toward the North, in such places where the Suns Horizontle motion
is very oblique, for there the hour may be given by the Compass with-
out any great error, but else-where it cannot. Therefore those that
travel must either use the Globe, or an Equinoctial Dial by whom
time may be most certainly measured, if there be good consideration
of the variation of the Needle by which the Equinoctial Dial is di-
sected, for this is a general thing to be regarded, as well as the Com-
pass, as any Dials, or other Instrument, or conclusion whatsoever
whatsoever wherein the use of the Needle is required, that unless there be
good regard unto the variation of the same, there can be no god Conclu-
sion follow of any such practices.
(follows compass rose with points named)
What is the next necessary thing to be learned ?
Having perfectly learned the Compass, the next necessary thing for
a Seaman to know, is the alteration or th_fting of Tydes, that
thereby he may with the greater safety bring his ship into any barred
Port, Haven, Creek, or other place, where Tydes are to be regarded.
And this difference of Tydes in the alteration of flowing and reflow-
ing, is by long experience found to be governed by the Moons motion, for
in such proportion of time as the Moon both separate her self from the
Sun, by the swiftness of her natural motien: in the like proportion of
time both one Tyde differ from another, therefore to understand this
difference of the Moons motion, is the only mean whereby the time of
Tyde is most precisely known.
Of the Moons Motion.
Yeu must understand the Moon hath two kinds of Motions: a na-
tural motion, and a violent motion: her violent motion is from
the East toward the West, raused by the violent swiftnes of the diur-
nal motion of Primum Mobilie, in which motion the Moon is carried
about the Earth in 24 hours and 50 minutes neerest one day with ano-
ther, for although the diurnal period of the first Mover be performed
in 24 hours, yet because the Moon every day __her flowest natural mo-
tion moveth 12 degrees, therefore she is not carried about the Earth
until that her motion be also carried about, which is in 24 hours and
50 minutes nearest.
Her natural Motion is from the West toward the East, contrary
to the motion of the First Mover, wherein the Moon hath three dif-
ferences of moving, a swift motion, a mean motion, and a flow moti-
on: all which is performed by the Divine Ordinance of the Creater
in 27 daies and 8 hours nearest, through all the Deg. of the Zodiack.
Her slow Motion is the in the point of Auge or Apogeo, being then far-
theist distantant from the Earth, and then she moveth in every day 12 de-
Her swift motion is in the opposite of Auge or Perigeo, being mearest
onto the Earth at which times she moveth 14 degrees, with small
difference of minutes in every 24 hours.
Between those two Points is her mean Motion, and then she mo-
veth 13 degrees nearest: all which differences are caused by the excen-
tricity of her Orbe wherein she moveth and are only performed in
the Zodiack, but the Seamen for their better ease in knowledge of the
Tydes, have applied this the Moons motion to the points, degrees,
and minutes of the Compass, wherebyf they have framed it to be an Ho-
rizontle motion, which __uth by long practice is found to be a rule of such
certainty, as that the arror thereof bringeth no danger to the expert
Seaman, therfore it is not amis to follow their practised precepts
In every 29 dayes 12 hours 44 minutes, with another through the
year, the Sun and Moon are in conjunction and therefore that is the
quantity of time between Change and Change, for although the Moon
in 27 days and 8 hours, performing her natural motion, both return
to the same minute of the Zodiack from whence she departed, yet being
so returned, she doth not find the Sun in that part of the Eliptick
where she left him, for the Sun in his natural motion moving every
day 1 degree toward the East, is moved so far from the place where
the Moon left him, as that the moon cannot overtake the Sun to come
in Conjunction with him, unitl she have performed the motion of 2
days 4 hours, and 44 minutes nearest, more than her natural revolu-
tion, and that is the Cause wherefore there are 29 days 12 hours, 44
minutes between Change and Change one with another through the
whole year: but the Seaman accomp_eth the Moons motion to be uni-
form in all places of teh Zodiac alike, limiting her general separati-
on from the Sun to be such as is her slowest natural motion, which is
12 degrees, or 48 minutes of time, and in every 24 hours.
By which accompt there are 30 dayes reckoned between the Change
and Change, being 11 hours, 16 minutes, more than in truth there
is: but because this difference breedeth but small error in their accompt
of Tydes, therefore to alter practised Rules where there is no urgent
cause, were a matter frivolous, which considered I think it not amiss
that we proceed therein by the same method that commonly is exercised
Allowing the Mood in every 24 hours to depart from the Sun 12
degrees, or 48 minutes of time, and in this separation, the Moon mo-
veth from the Sun Eastward, until she be at the Full: for between
the Change and the Full, it is called the Moons separation from the
Sun: for after the Full, she both apply towards the Sun, so that be-
tween the Full and the Change, it is called the Moons Application to
the Sun, in which time of Application she is to the Westward of the
Sun, as in her separation she is to the Eastward, or I may say in the
Seamans phrase all the time of her application is before the Sun,
and in the time of her separation she is abaft the Sun.
Then if the Moon do move 48 minutes of time in 24 hours, it follow-
eth that she doth move 24 minutes in 12 hours, and in 6 hours she mo-
veth 12 minutes: therefore every hour she moveth 2 minutes, and such
as is the difference of her motion such is the alteration of the Tydes, and
therefore every Tyde differeth from the other 12 minutes, because there
is 6 hours between Tyde and Tyde: and in every hour the course of
flowing or reflowing altereth 2 minutes, whereby it appeareth that in
24 hours the four Tydes of flowing and reflowing do differ 48 min.
of time. Anduth the whole knowledge of this difference or alteration of
Tydes, as also the quantity of the Moons Separation and Application
to, and from the Sun, dependeth upon the knowledge of the Moons
age, it is therefore necessary, that next you learn how the Sun may be
For the performance whereof, there are two Numbers especially re- ]
quired named the Prime and the Epact, for by the Prime the Epact is ] *
found, and by help of the Epact the Moons age is known. ]
Of the Prime, or Golden Number.
The Prime is the space of 19 years in which the Moon per-
formeth all the varities of her motion with the Sun, at the end
of 19 years beginneth the same Revolution again, therefore the prime
never accedith the number of 19 and this Prime both always begin
in January, and thus the Prime is found: Unto the year of the Lord
wherein you desire to know the Prime, add 1, then divide that num-
ber by 19, and the remaining number which commeth not into the quo-
tient is the Prime.
Example: In the year of our Lord 1590, I desire to know the
Prime, therefore I added 1 unto that year, and then it is 1591, which
I divided by 19, and it yieldeth in the Quotient 83, and there remain-
eth 14 upon the division, which cometh not into the Quotient which
14 is the Prime in the year of our Lord 1590.
_______ 1591 (83
1591 199 ????
The Epact is a number proceeding from the over-plus of the Solar
and Lunar year, which number never exceedith 30, because the
Moons age never exceedith 30, for the finding whereof this number
only serveth: and thus the Epact is known, which Epact doth always
begin in March, multiply the prime by 11 (being the nearest difference
between the Solar and Lunar year) divide the product by 30 and the
remainder is the Epact. Example : In the year of our Lord 1590 I
would know the Epact, first I seek the Prime of that year, and find
it to be 14, I therefore multiply, 14 by 11 and that yieldeth 154, which
being divided by 30, it giveth the quotient 5, and there remaineth
4 upon the division, which 4 is the Epact in the year 1594, which be-
ginning in March, both continue until the next March of the year 1591.
11 25 (4(5
* Note: these 3 lines were not in the 1643 edition.
Epact = intercalary. a) The period of about 11 days by which the solar
year exceeds the lunar year of 12 months.
b) The age, in days, of the calendar moon on the first of the year.
Of the Solar and Lunar Year.
The Solar year, or the Suns year, consisteth of 12 months, being
365 days and about 6 hours, the Lunar year or the Moons year,
containeth 12 moons, and every moon hath 29 days, 12 hours, 44
minutes nearest, which amount unto 354 days, 5 hours, 28 minutes,
the content of the Lunar year, which being subracted from 365 days,
6 hours, there resteth 11 days and 23 minutes, the difference between
the said years, from which difference the Epact commeth.
By this Table the Prime and Epact may forever be found, for when
the year be expired, you may begin again and continue it forever
at your pleasure.
(insert circular diagram)
How to find out the Moons Age:
The first Circle containeth Years of our Lord, the second the
Prime, and the third and inner Circle sheweth the Epact: under e-
very year you shall find his Prime and Epact, the Prime beginneth in
January, and the Epact in March.
First, Consider the day of the Month wherein you seek the Moons
age, then note how many Months there are between the said Month
and March, including both Months, unto those Numbers adde the Epact
of that year, that is, you must adde into the one sum the day of the Month,
between March and your Month, reckoning both Months and the Epact,
all which numbers joyned together, if they exceed* not 30 is the Moons
age, if they be more than 30, cast away 30 as often as you can, and the
remainder is the Moons age, if it be just 30 it is then New Moon, of
the last Quarter day, if 15 it is Full Moon, if 22 it is then
the last Quarter day, andthus the Moons age is found forever.
And now being able for all times either past, present, or to come,
to give the Moons age, I think it good by a few Questions convent-
ent for the Seamans practice, to make you understand the necessary
For the account of Tydes.
When you desire to know the time of Full Sea in any place at all
such seasons as occasion shall require, you must first learn what
Moon maketh a Full Sea in the same place, that is, upon what point
of the Compass the Moon is, when it is Full Sea at the said place,
you must also know what hour is appropriated* to that pointof the Com-
pass as before is shewed: For upon the Change day it will always
be Full Sea in that place, at the same instant of time, by which con-
siderations you must thus proceed for the search of Tydes.
Multiply the Moons age by 4, divide the product by 5, and to the
Quotient adde the hour, which maketh Full Sea in that place upon
the Change day: if it exceed 12, cast away 12 as oft as you may, and
then the hour of Full Sea remaineth: and for every 1 that resteth
upon your Division, allow 12 minutes to be added to the hours, for 2.
24 minutes: for 3,36: and for 4,48 minutes: for more then 4 will
never remain: and thus you may know your Tydes to a minute:
Example: The Moon being 12 days old, I desire to know the
time of Full Sea at London: First it is found by experience, that a
Southwest and Northeast Moon makes Full Sea at London: next I
consider that 3 of the Clock is the hour appropriated to that point of
the Compass, which number I keep in memory, then I multiply the
Moons age, being 12 by 4, and that yieldeth 48, which being divi-
ded by 5, it givith the Quotient 9, and 3 remaineth: I adde the
Quotient 9 to the bout* 3 and it maketh 12 hours: and for the remain-
ing number 3, I also adde 46 minutes so that I find when the Moon
is 12 days old, it is 12 of the Clock and 36 minutes past, at the in
stant of the Full Sea at London: &y this order you may at all places &
times know the certainty of your Tydes at your pleasure.
But those that are not practiced in Arithmatick, may account these
Tydes in this sort, knowing how many daies old the Moon is he must
place the Moon upon that oint of the Compass which maketh Full Sea
at the place desired, & then reckoning from that point with the Sun ac-
cording to the diurnal motion, must account to many points, and so
many times 3 minutes, and there finding the Sun, he must consider
what is the hour allowed to that point where he findeth the Sun, for
that is the Hour of Full Sea.
As for Example: The Moon being 12 daies old, I desire to know
the hour of Full Sea at London, now finding by former experience,
that a Southwest Moon maketh Full Sea at London, I Therefore
place the Moon upon the point Southwest, then I account from the
point Southwest 12 points, reckoning with the Sun according to the
diurnal motion, Southwest and by West for the first point, West
Southwest for the second, West by South for the third, West for the
fourth point, and so forth, until I come to North, which is 12 points
from the Southwest, and because the Moonmoveth 3 minutes more
than a point in every day, I therefore add 3 times twelve which make
36 minutes to the point North, at which place I find the Sun to be, and
knowing that 12 of the clock is appropriated to the point North. I
may therefore boldly say that at twelve of the Clock 26 minutes past, it
is Full Sea at London, when the Moon is 12 days old, which 36 mi-
nutes are added, because the Moon hath moved 36 minutes more than
12 points in those 12 days, which is 1 point and 3 minutes for every
day, as before.
Here followeth a very necessary Instru-
ment for the knowledge of the Tydes, named
An Horizontle Tyde-Table.
Of this Instrument, and his Parts.
This necessary Instrument for the young practicing Seamans use,
named, a Horizontle-Tyde-Table, whereby he may shift his Sun
and Moon (as they term it) and know the time of his Tydes with ease
and very certainly. (Besides the answering of may pleasant and
necessary Questions used among Mariners) I have contrived into
this method, only for the benefit of such young practicers in Naviga-
The first part of this Instrument is a a Sea Compass, divided into
32 points, or equal parts: the innermost circle of which Compass
is divided into 24 hours, and every of those into 4 quarters, each quar-
ter being 15 minutes, and against every point of the Compass those
places are layd down, in which places it is Full Sea when the Moon
cometh upon the same point, so that whatsoever is required as touch-
ing time, or the points of the Compass is there to be known.
The next movabl circle upon this Compass, is limited to the Sun,
upon whose Index the Sun is laid down, which Circle is divided into
30 equal parts or days, signifying the 30 days between Change and
Change according to the Seamans account, so that whatsoever is de-
manded as touching the age of the Moon, is upon that Circle to be
The uppermost moveable Circle is applied to the Moon upon whose
Index the Moon is laid down, which is to be placed either to the points
and parts of the Compass, or to the time of her age, as the Question
requireth: which considered, the use of this Instrument is largely ma-
nifested, by these Questions and theire Answers following.
How to know the hour of the Night by the Moon,
being upon any point of the Compass
by this Instrument.
1. Q. The Moon 10 days old, I demand what is a Clock when
she is East Northeast ?
1. A. In this Question the Moons age and the point of the Com-
pass is given, thereby to know the hour, I therefore place the Index of
the Moon upon the point East Northeast, there keeping the same not
to be moved, then because the Moon is 10 days old, I move the In-
dex of the Sun until I bring the 10 day of the Moons age unto the In-
dex of the Moon, and there I look by the Index of the Sun, and find
upon the Compass that it is 12 of the Clock at noon and 30 minutes
past, when the Moon is upon the point East Northeast, being 10 days
2. Q. The Moon being 12 days old I demand at what hour she
will be upon the point S.S.E ?
2. A. In this Question the point of the Compass and Moons age
is given as in the first, therfore I place the Index of the Moon upon the
point S.S.E. And there holding it without moving, I turn the Index
of the Sun, until the twelfth day of the Moons age come to the Index
of the Moon, and then the Index of the Sun showeth me upon the Hori-
zon the hour 8 therefore I say that 8 of the clock at night, the Moon
was upon the point South Southeast.
And thus you may at all times know the hour of the night by the
Moon, upon any point of the Compass, so that the Moons age be also
How by this Instruction, you may know at all times upon
what point of the Compass the Moon is.
1. Q. When the Moon is 10 dyas old, upon what point of the
Compass shall be at 9 of the Clock in the morning ?
1. A. In this Question the hour of the day and the Moons age is gi-
ven, thereby to find upon what point of the Compass she is at the same
time. I therefore place the Index of the Sun upon the Compass, at
the hour 9 of the Clock in the morning being upon the point Southeast,
then I turn the Index of the Moon untill I bring it to the 10 day of her
age, and then I see upon the Compass, that the Moon is North and by
East, and 15 minutes to the Eastwards, of the 9 of the Clock when she is
10 days old.
2. Q. When the Moon is 20 days old, upon what point of the
Compass will she be at 2 of the Clock in the afternoon ?
2. A. I place the Index of the Sun upon the hour 2, noted in the
Compass, there holding the same without moving, then I trun the
Index of the Moon until I bring it unto the 20 day of her age, and there
I see upon the Compass that she is Northeast and by North, and 15
minutes to the Northward, at 2 of the Clock in the afternoon, when she
is 20 dayes old.
To find the Moons age by this Instrument.
1. Q. When the Moon is North at 7 of the Clock in the fore-
noon how old is she ?
1. A. In this Question the point of the Compass and the hour is
given, for the finding of the Moons age: therefore I set the Index of the
Sun upon the hour 7 in the forenoon, there holding it without moving,
then I bring the Index of the Moon to the point North, and then upon
the Circle containing the dayes of the Moons age, I see the Moon is 8
dayes, and about 18 hours old, when she is North at 7 of the Clock in
2. Q. When the Sun is East, and the Moon Southeast, how old
is the Moon.
2. A. In this Question the points of the Compass are only given
for the finding of the Moons age, therefore I awr rhw Inswz of the Sun
upon the point East, there holding him steady, then I put the Index
of the Moon upon the point Southwest, and there I see that the Moon
is 18 dayes and 19 hours old, when the Sun is East, and the South-
After this order by the variety of these few Questions, you may
frame unto your self many other pleasant and necessary Questions,
which are very easily answered by this Instrument: and entering into
the reasons of their Answers, you may very readily by a little practice,
be able by memory to Answer all such Questions with ease.
How to know the time of your Tydes by this Instrument.
1. Q. When the Moon is 12 days old, I desire to know the time
of full Sea at London.
1. A. To answer this Question, I first look through all the points
of the Compass of my Instrument, until I find where London is writ-
ten, for when the Moon cometh upon the point of the Compass, it will
then be full Sea at London: Therefore I place the Index of the Moon
upon the same point, which I find to be Southwest of Northeast there
holding the Index not to be moved, then I turn the Index of the Sun
until I bring the 12 day of the Moons age to the Index of the Moon,
and then the Index of the Sun sheweth me that at 12 of the Clock 36
minutes pst it is full sea at London, the Moon being 12 days old.
2. Q. The Moon being 21 days old, at what time is it Full Sea
2. A. I find upon my Instrument that Dartmouth is noted upon the
points East and West, whereby I know that when the Moon is East
or West, it is always Full Sea at Dartmouth: Therefore I place the
Index of the Moon upon the point East, and there holding it without
moving, I turn the Index of the Sun, until I bring the 21 day of the
Moons age unto the Index of the Moon, and the Index of the Sun
sheweth me upon the Compass, that at 10 of the clock and 48 minutes
past, it is Full Sea at Dartmouth, when the Moon is 21 days old, and
not only at Dartmouth, bur my Instrument sheweth me that at the
same instant it is full Sea at Exmouth, Weymouth, Plymouth, Mounts Bay,
at Linne, and at Humber: and thus with great facility the time of flow-
ings and reflowings is most precisely known.
And now that there may be a final end of the uses and effects of the
Compass, it is convenient that I make known unto you how many
leagues shall be sailed upon every particular point of the Compass, for
the raising or laying of the degrees of latitude, and in the distance sail-
ing how far you shall be separated from the meridian from whence the
said courses are begun, for as every point of the Compass hath his cer-
tain limited distance for the degrees of the Pole elevation, so do they
likewise lead from longitude to longitude, every point according to his
ratable limits, which differnces of leagues are without alteration,
keeping one and the same positon in every particular Horizon of any
latitude, but the degrees of longitude answerable to such distances, do
differ in every altitude, according to the nature of the parallel, as here-
after shall be more plainly manifested.
And now know that in sailing North and South, you depart not from
your meridian, and in every 20 leagues sailing you raiseth a degree:
North and by East raiseth a degree in sailing 20 leagues and one mile,
and leadeth from the meridian 4 leagues: North-North-east raiseth a
degree in sailing 21 leagues and 2 miles, leadeth from the meridian
8 leagues and 1 mile: Northeast by North, raiseth a degree in sailing
24 leagues, and leadeth from the meridian 13 leagues and a mile:
NorthEast raiseth a degree in sailing 28 leagues and a mile, and lead-
eth from the meridian 20 leagues: Northeast by East raiseth a degree
in sailing 36 leagues, and leadeth from the meridian 30 leagues,
East North East raiseth a degree in sailing 52 leagues and a mile, and
leadeth from the meridian 48 leagues and 2 miles: East and by North
raiseth a degree in sailing 102 leagues and a mile, and leadeth from
the meridian 100 leagues and 2 miles: East and West do no raise
or lay the Pole, but keep still in the same Parallel: The like al-
lowance is to be given every quarter of the Compass, as is laid
down upon this Northeast quarter.
Leagues separated from the Meridian in raising a degree.
Q. I perceive that degrees are to great purpose in Navigation.
What is a degree ?
Answ. It is most true that Degrees are of very great employment
in Navigation, and a Degree is the 360 part of a Circle,
how big or litle soever the Circle be, being applied after the several
sorts, for the better perfections of the practises Gubernautick, so that
there be degrees of Longitude, degrees of Latitude degrees of Azu-
muth, degrees of Altitude, degrees applied to Measure and degrees
applied to Time.
A Degree of Longitude is the 360 part of the Equinoctial.
A Degree of Latitude is the 360 part of the Meridian.
A Degree of Azumuth is the 360 part of the Compass, or Hori-
A Degree of Altitude is the 90 part of the Vertical Circle, or the
90 part of the distance between the Zenith and the Horizon.
Every Degree applied to measure, doth contain 60 minutes, and e-
very minute 60 seconds, and every second 60 thirds etc. and every de-
gree of a great Circle so applied containeth 20 leagues, which is 60
miles, so that every minute standeth for a Time in the accompt of mea-
sures, and a mile is limited to be 1000 paces, every pace 5 foot, every
foot 10 inches, and every inch 3 barley corns dry and round, after our
English accompt, which for the use of Navigation is the only best of
all other: So by these rates of measure you may prove that a Degree
is 20 leagues, or 60 miles, a minute is a mile, or 5000 feet, a second
is 83 feet, and 2 thirds; and a third is 16 inches and 2 thirds: and
thus much of a Degrees and their parts applied to measure.
Of Degrees applied to Time, there are 15 contained in every hour,
so that every degree of Time standeth in the accompt of Time for four
minutes, for an hour consisth of 60 minutes of Time, hath for his fif-
teenth part 4 minutes, so that a degree being the fifteenth part of an
hour, containeth 4 minutes of time so that 15 degrees, or 60 minutes
make an hour, 24 hours make a natural day, and 365 days 6 hours
are contained in a year: and thus much as touching Time and De-
grees applied to Time.
What is the use of Degrees ?
The use of a Degree is to measure between place and place,
to find Altitudes, Latitudes, and Lontitudes, to describe Coun-
tries, to distinguish Courses, to find the variation of the Compass, to
measure time, to find the places and motions of all Celestial Bodies,
as the Sun, Moon, Planets, and Stars: To conclude, by Degrees
have been performed al Mathemetical observations whatsoever, whose
use is infinite.
What is tha Poles Altitude, and how it may be known.
Altitude is the distacne, height, or mounting of one thing above a-
nother, so that the Altitude of the Pole, is the distance, height, of
mounting of the Pole from the Horizon, and is defined to be that posi-
tion of the Meridian which is contained between the Pole and the Hor-
izon, which Altitude or Elevation is to be found either by the Sun, or
by the sired Stars, with the help of your Cross-Staff, Quadrant, or
Astrolaby, but the Cross-Staff is the only best Instrument for the Sea-
And in the observation of this Altitude there are five things especial-
ly to be regarded: the first is, that you know your Meridian distance
between your Zenith and the Sun or Stars, which by your Cross-Staff
or Astrolaby is given: the second, that the declination be truly known
at the timeof your observation. And the other three are, that you con-
sider whether your Zenith be between the the Equnoctial and the Sun or
Stars, or whether they be between your Zenith and the Equator, for there is
a several order of working upon each of these differences.
Latitude you must also know, That so much as the Pole is above
the Horizon, so much is the Zenith from the Equinoctal, and this di-
stance between the Zeith and the Equator is called Latitude or wide-
ness, and is that position of the Meridian which is included between
your Zenith and the Equator: for it is a general Rule for ever, That
so much as the Pole is above the Horizon, so much the Zenith is from
the Equinoctal: so that in this sense, Altitude and Latitude ia all one
thing, the one having relation to that part of the meridian, contained
between the Pole and the Horizon: and the other to that part of the
meridian which is containied between the Zenith and the Equinoctal.
You must further understand, that between the Zenith and Hroizon,
it is a quarter of a great Circle containing 90 degrees so that know-
ing how much the Sun or any Star is from the Horizon, if you take
that distance from 90, the remainder is the distance between the said
Body, and the Zenith.
As for Example: If the Sun be 40 degrees 37 munutes from the ho-
rizon, I subrtact 40 degrees 37 minutes from 90, and there remain-
eth 49 degrees 23 minutes, which is the differance between my Zenith
and the SUn, &tc. Those Instruments that begin toe accompt of their
degrees at the Zenith, concluding 90 in the Horizon, are most ease
for the finding of the Latitude by the Sun or fixed Stars, because they
give the difference between the Zenith and the Body observed without
further trouble, and that is the number which you must have, and for
which you do search in your Observation: All which things considered,
you must in this sort proceed for the finding of the Poles height or Al-
By the Sun, or fixed Stars, being between the Zenith
and the Equinoctial, the Latitude is thus found,
in what part of the world soever
First, Place the Cross-Staff to your Eye, in such good sort as that
there may grow no error by the disorderly using thereof, for unless
the Center of your Staff, and the Center of your Sight do joyn toge-
ther in your observation, it will be erroneous what you conclude there-
by: Your Staff so ordered, then move the Transversary upon your
Staff to and fro as occasion requireth, until at one and the same instant
you may set by the upper edge of your Transversary, halfe the body of the
Sun, or Stars, or that the lower edge of or end thereof so likewise touch
the Horizon, at that place where it seemeth that the skie and the Seas are
joyned, having special regard in this your observation, as that you
hold the Transversary as directly uprightly as possible you may, and
you must begin this observation somewhat before the Sun or Stars be
at South, and continue the same so long as you percieve that they rise:
for when they are at the biggest, then are they upon the Meridian, and
then you have the Merioninal altitude which you seek, at which time
they will bedue South from you if your Compass be be good and without
variation, and then both the Transversary shew upon the staff the
degrees and minutes that the said body is from your Zenith, if the de-
grees of your instrument be numbered from the Zeinith toward the
Horizon: or else it shewith the distance between the said body and the
Horizon, if the degrees of your Instument be numbered from the Horiz-
ion, concluding 90 in the Zenith, as commonly Cross-Staffs are
marked, which is not the easiest way: but if your staff be a accompted
from the Horizon, then subtract the degrees of your observation from
90, and the remainder shewith the distance between your Zenith and
the Sun or Stars, which is the number you must know: unto that
number so known by your instrument, add the declination of the bo-
dy by which you do observe, whether it be the Sun or ante Star, and
that which cometh by the addition of those two numbers together, is the
Poles height, or the Latitude of the place where you are: as for Ex-
ample, In the year of our Lord 1621, the third day of March, the Sun
being then between my Zenith and the Eqinoctial, I observed the
Suns Meridional altitude from the Horizon to be 72 degrees and 20
minutes, but because I must know the distance of the Sun from my Ze-
nith, I therefore subract 72 degrees 20 minutes from 90 degrees, and
there remaineth 17 degrees 40 minutes, the distance of the Sun from
my Zenith, to that distance I add the Suns declination for that day,
which by my Regiment I find to be 43 minutes 2 degrees of South de-
clination, and it amounteth unto 20 degrees 23 minutes, so much is the
South Pole above the Horizon, and so much is my Zenith South from
the Equinoctical, because the Sun having South declination, and being
between me and the Equinoctical, therefore the necessity the Antarctick
Pole must be above my Horizon.
89 -- 60 -- the distance between the Zenith and the Horizon.
72 -- 20 -- the Suns Altitude.
17 -- 40 -- the Suns degree from the Zenith.
2 -- 43 -- the Suns Declination.
20 -- 23 -- the Poles height.
When the Equinoctial is between your Zenith and the Sun or Stars
the Altitude is thus found in all places.
By your Instrument, as before is taught, you must sa___ the Merdio-
nal distance of the Sun or Stars from your Zenith: which being
known, subtract the Declination of the Sun or Stars from the said di-
stance, & the remaining number is the Poles height, or latitude which
you seek: Example.
The 20 of October 1625. I find by my Instrument that the Sun is
60 deg. 45 minutes from my Zenith at Noon, being then upon the
Meridian, the Equator being then between my Zenith and the Sun:
I also find by my Regiment that at that time the Sun had 13 deg. 57
min. of South Declination, because the Equinoctical is between me
and the Sun, therefore I subract the Suns declination from the ob-
served distance, and there resteth 46 deg. 48 min. the latitude desired:
and because the Sun hath the South declination, and the Equinoctical,
being between me and the Sun, therefore I may conclude that the Pole
Artick is 46 deg. 48 min. above my Horizon so that my Zenith is so
much toward the North from the Equator.
60 -- 45 -- the Suns distance.
13 -- 57 -- the declination.
46 -- 48 -- the latitude.
When your Zenith is between the Sun or Stars and the Equinoctial,
the Latitude is thus found.
By your Instrument, as in the first example is shewed, you must ob-
serve the Meridional distance, of the Sun or Stars from your Ze-
nith: you must also by your Regimient or other Tables search to know
the Declination of that body which you observe, then subtract the ob-
sed distance from your Zenith out of the Declination, and the re-
maining number is the Latitude desired: Example. The Sun ha-
ving 20 deg. of North declination, and being upon the Meridian is 5
deg. 9 min. from my Zenith, I therefore subtract 5 deg. 9 min from
20 deg. and there resteth 14 deg. 51 min. the Latitude desired: and
because the Sun hath North Declination, my Zenith being between
the Sun and the Equinoctical, therefore I conclude. That the North
Pole is 14 deg. 51 min. above my Horizon.
19 -- 60 -- the Declination.
5 -- 9 -- the Suns distance from my Zenith
14 -- 51 -- the Poles height.
How shall I know the true order of placing the Cross-Staff to
mine eye, to avoid error in my observation ?
To find the true placing of the Staff at your Eye, thereby to amend
the Parallax, or false shadow of your ____ do thus: Take a staff
having two crosses, a long Crosse which endith in 30 degrees, and a
short Cross which beginneth at 30 degrees where the long Cross en-
deth, put the long Cross upon his 30 degrees, and there make him fast:
then put the short cross likewise upon his 30 degrees, there fasten him
without moving: then set the end of your staff to your Eye, moving it
from place to place about your Eye, until at one instant you may see the
end of both Crosses, which when you find, remember that place and
toe standing of your body, for so must your Staff be placed, and your Bo-
dy ordered in all your Observations.
Are these all the Rules that appertain to the finding
of the Poles height ?
Those that Travel far towards the North, under whose Horizon
the Sun setteth not, shall sometime have occasion to seek the Lati-
tude by the Sun, when the Sun is North from them, the Pole being
then between the Sun and their Zenith. When such observations are
made, you must by your Instrument seek the Suns height from the
Horizon, subtract that height from his Declination, and the remain-
ing number sheweth how far the Equinoctial is under the Horizon up-
on the point North for so much is the opposite part of the Equator a-
bove the Horizon upon the point South, subtract that Meridian La-
titude of the Equinoctial from 90, and the remaining number is the
Poles height desired: Example.
The Sun having 22 degrees of North declination, his Altitude from
the Horizon is observed to be 3 deg. 15 min. therefore subtracting 3
deg. 15 min. from 22 degrees, there rest 18 deg. 45 min. which is the
distance of the Equinoctical from the Horizon, which being taken from
90, there resteth 71 deg. 15 min. the Poles elevation desired.
21 -- 60 -- the Suns Declinations.
3 -- 15 -- the Suns Altitude.
18 -- 45 -- the Altitude of the Equinoctical.
89 -- 60 -- the distance between the Zenith and Horizon.
18 -- 45 -- the Altitude of the Equator.
71 -- 15 -- the Altitude of the Pole.
But you must know, That the Declination found in your Regiment
is not the Declination which in this case you must use: for the Regi-
ment sheweth the Suns Declination upon the Meridian or South
point, in the place for whose Meridian the same was calculated, and
not otherwise: Therefore it is necessary to know the Suns Declina-
tion at all times, and upon every point of the Compass: for I have
been constrained in my Northwest Voyages, being within the Frozen
Zone, to search the Latitude by the Sun, at such time as I could see
the Sun, upon what point of the Compass soever, by reason of the
Fogs and Mists that those Northern parts are subject unto: And
there is consideration also to be had upon every difference of Lontitude
for the Suns Declination, as I have by my experience found at my be-
ing in the Straits of Magilane, where I have found the Suns Declina-
tion to differ from my Regiment calculated for London, by so much as
the Sun declineth in 5 hours, for so much is the difference between the
Meridian of London, and the Meridian of Cape Froward, being in the
midst of the said Straits.
How may this Declination be found for all
times, and upon all points of the
First, Consider whether the Sun be comming towards the Equinocti-
al, or going from him: That being known, consider the time
wherein you seek the Declination, then look for the Suns Declination
in your Regiment for that day, and also seek his Declination for the
next day, subtract the lessor out of the greater, and the remainder is
the whole declination which the Sun declineth in 24 hours, or in his
moving through all points of the Compass, from which number
you may by the Rule of Proportion find his Declination upon every
point of the Compass for every hour of the day, as by these Examples
In the year 1625, the 20 of March, I desire to know the Suns De-
clination when he is upon the North part of the Meridian of London,
I seek the Suns Declination for that day, and find it to be 3 deg. 59
min. the Sun then going from the Equator. I also search his Decli-
nation for the next day, being the 21 day of March, and find it to be 4
deg. 22 min. I then subtract 3 degrees 59 minutes from 4 degrees
22 * minutes, and there resteth 23 minutes so much the Sun doth decline
in 24 hours, or in going through all the points of the Compass. Then
I say by the rule of Proportion, if 24 hours give 23 minutes of Decli-
nation, what will 12 hours give, &c. I Multiply and Divide, and
find it to be 11 min. 30 sec. the Suns Declination in 12 hours motion
to be added to the Declination of the 20 day being the Suns going
from the Equator: Or for the points of the Compass, I may say, if
32 points give 22 min. of Declination, what will 16 points give,
* textual variation, seems to be 12 in the 1657 version
which is the distance between South and North: I Multiply and
Divide as the rule of Proportion requireth, and find that 16 points
give 11 min. the Suns Declination in moving through 16 points of
the Compass, which is to be added to the Declination of the 20 day,
because the Sun goeth from the Equator, so I conclude the Declina-
tion to be 3 deg. 52 min. the Sun being North the 20 of March.
In this work the 30 seconds are omitted.
ho. mo. ho.
24 -- 23 -- 12 -- 11
22 xxx (11
po. m. po. m.
32 -- 22 -- 16 -- 11
132 xxx (11
Being West from the Meridian of London 90 degrees of Longi-
tude, I desire to know the Suns Declination when the Sun is upon
the Meridian the 20 of March 1625, I must here consider that 90 deg.
of Longitude makes 6 hours of Time, for every hour containeth 15
deg. whereby I know that when the Sun is South at London, he is
but East from me, for when it is 12 of the Clock at London, it is but
6 of the Clock in the morning with me: & when it is 12 of the Clock
with me, it is then 6 of the Clock in the afternoon at London: there-
fore I must seek for the Declination of the Sun at 6 of the clock in
the afternoon, and that is the Meridional Declination which I must
use being 90 degrees West from London, which to do the last Example
both sufficiently teach you, whereby you may easily gather the perfect
notice of whatsoever is requitue in any of these kind of observations,
If you read with the eye of Reason, and labour to understand with
judgement that you read.
The day and year proposed being the 20 of March 1625: Declina-
tion the 3 deg. 59 min. the next dsy the 21 of March 4 deg. 22 min. De-
duction made resteth 23 min. the proportionall part to be found for 90
deg. West, 026 hours of time. Day if 24 hours give 23. What 6
hours ? Facit 5 min. 18 seconds which being that the Declination en-
creaseth abbe 5 min. 18 seconds, to the Declination for the day pre-
fired: that total is the Meridional Declination for 90 deg. of
Westerly longitude from the meridian of London.
There is another way most excellent for the finding of the Suns De-
clinationn at al times, that is to search by the Ephemerides the Suns
true place in the Ecliptick for any time proposed whatsoever, and then
by the Tables of Sinus the Declination is thus known: Multiply the
Sinus of the Suns Longitude from the Equinoctial points of Aries or
Libra, to which soever be nearest, by the Sinus of the Suns greatest
Declination, and divide the Product by the whole Sinus, and the Arke
of the Quotient is the Declination desired: but because Seamen are
not acquainted with such Calculations, I therefore omit to speak
further thereof, fith this plain way before taught is sufficient for their
The Use of this Instrument.
By this Instrument you may sufficiently understand, the reasons of
whatsoever is before spoken for the finding of the Poles Elevation,
or the latitude of your being: into the consideration whereof be-
cause the young practiser may the better enter, I thinke it not amisse by
a few examplesto express the necessary use thereof.
1. Q. The Sun being 7 deg. of North Declination and the Pole
Articke being 45 deg. above the Horizon, I demand what will be the
Suns Meridional distancefrom my Zenith.
1. A. First I turne the Horizon until I bring the North Pole to be
45 deg. above the same, there holding the Horizon not to be moved. I
then bring the third* that is falted* to the Center of the Instrument,
7 degrees from the Equinoctial towards the North, because the Sun
* = word that is unclear in both versions.
hath so much North Declination, and the third* both shew me upon the
vertical Circle, that the Sun is 38 deg. from the Zenith.
2. Q. The Pole Artick being 50 deg. above the Horizon, and the
Suns distance 30 deg. from the Zenith, I demand what is the Suns
2. A. As in the first question I place the North Pole 5 deg. above
the Horizon, there holding the Horizon not to be moved, then I bring
the third* to the 30. deg. upon the vertical Circle, because the Sun is 30
deg. from my Zenith, and the third* sheweth upon the Meridian
between the Tropick of Cancer and the Equinoctical, that the Sun hath
20 degrees of North Declination.
3. Q. The Sun having 10 deg. of South Declination, being upon
the Meridian, is 53 deg. from my Zenith, I demand what is the
Poles height ?
3. A. In the first question the Precise height and the Suns decli-
nation are given for the finding the Suns meridional distence from
the Zenith, In the second the Poles height is given, and the Suns
meridional distance from the Zenith, thereby to find the Suns de-
clination, And in this question the Suns declination and meridionall
distance, is given for the finding of the Poles height. I therefore
bring the third* fa__ned in the Center of the Instrument 10 degrees
South from the Equator, between the Equinoctiall and the Tro-
picke of Capricorne, there holding the third not to be moved, I then
turne to the Horizon, untill I bring the 53 degree of the verticall cir-
cle under the third, and then the Horizon seweth me, that the North
Pole is 43 degrees above the same.
4. Q. The Sun having 12 degrees of South declination, and be-
ing upon the Meridian South from me, is 30 degrees above the Ho-
rizon. I demend how far the Sun is from my Zenith, how much
the Equinoctall is above the Horizon, and what is the Poles Height ?
4. A. First, I bring the third to the place of the Suns declination,
as before, there holding in not to be moved, then I turn the Horizon
untill I bring it to be 30 deg. under the third, and then the third
sheweth me that the Sun is 60 deg. from my Zenith, and the
Horizon sheweth that the Equinoctial is 42 deg. above the Hori-
zon; although these questions are so very easie and plain, as that
they may readily be ansered by memorie, yet because the reasons
how they are answered may the better appeare, is the cause where-
fore they are demanded, and in this sort answered, only for the benefit
of such as are not altogether expert in these practices, that thereby
they might likewise frame unto themselves questions of other
variety, and so gather thereby the more sufficient judgement in this
part of Navigation.
What is the Zenith ?
The Zenith is that prick, or point, in the heavens, which is direct-
ly over your head, from whence a line falling perpendicularly,
will touch the place of your being, and so passe by the Center of the
sphere and this line may be called the Aris of the Horizon, and the
Zenith the Pole of the same, being 90 d. from all parts thereof, as
by the former figure may most plainly appear.
The use of the Tables of the Sunnes declination. *
Because the height of the pole (which is equall to the latitude of
any place) cannot be exactly known, except you have the Suns
true declination; here are Tables of the Suns declination, ecaxtly cal-
culated for the years, 1649,1650,1651,1652. which will serve untill
the year 1672. without correction, because there will be no sensible
error in their use. And these are the plainest of any Tables of the Suns
declination, that are extant; the declination is nominated, whether it
be North, or South, Between the Colums and the Equinoctiall, is sig-
nified by three black lines in March, when the declination comes to
be North; and it is signified by one black line in September, when the
declination comes to the South; and there are the years in every
month for which the declination serveth at the top of the Tables, But
besides the Tables of declination, the whole book hath not any equall
to it, of its quantity, for the direction of lyoung beginners; there be-
ing in it the principles of the Sphere, and the ground and foundation
of Navigation, with divers other things, that are very usefull, com-
modious, and pleasant. But for a further description of the Tables,
you have in every month four great columns, each of them consisting
of three lesser columns; in the first column is the dayes of the month,
in the second is the degrees of the Suns declination, under the letter
G, and in the third is the minutes, under the letter M. The first of the
great columns serving for the first year after leap year; the second for
the second year; the third for the third year; and the fourth for the leap
years, viz. 1652, 1656, 1660, 1664, 1668, 1672.
To find the Suns declination at any time, first seek the month,
then the yeare of our Lord, and the day of the month, and right against
the day of the month, under the yeare of our Lord is the Suns de-
clination. Example. the 10th day of March, 1651. I desire to know
the Suns declination, in March I look for it, 1651. and find it over the
thrid great column, and right against the 10th day I finde 00 degrees
and 02 minutes South declination, and the likes is to be done for any
Click Here for the Tables of the Sunnes Declination
The rule of the Regiment (1643)
For as much as the Poles height cannot be observed by the Sunne,
unlesse the Sunnes true declination bee knowne, I have therefore carefully
calculated these Tables or Regiment, out of Origanus, for the yeares 1625,
6.7.and 8. which will serve untill the yeere 1644. without further
correction: and because there may grow no error by mistaking the yeares,
I have over every Moneth written the yeare of the Lord, in which the
declination of the same Moneth is to be used, therefore when in any yeare
and Moneth you seeke the Sunnes declination, first looke for the moneth,
and there you shall finde 4. of those Moneths, which are the Moneths
between the leape yeares, then looke over each of those moneths, untill
you find the yeare of the Lord, wherein you seeke the declination, and
directly under that year is the Moneth wherein you must seeke the Suns
declination: Example 1626. the tenth day of Feb. I would know the Suns
declination, first I seeke out February, & under the second yeare I see
the yeare 1626, therefore this is my Moneth, against the tenth day of
which Moneth I find that the Sun hath 10 deg. 49 min of South declination,
and after the like manner you must do in all the rest as occasion requireth.
(In the 1643 edition there follows 12 pages of tables, 4 columes per page.)
* titled "The use of the Regiment" in the 1643 version
The text is much different in the earlier version, as you see.
What is the Chart ?
The Sea Chart is a speciall instrument for the Seamans use
whereby the Hydrographicall description of the Ocean Seas, with
the answering Georgrphical limits of the earth, are supposed to be in
such sort given, as the longitudes and latitudes of all places, with
the true distance and course be between place and place, might be truly
known. But because there is no proportionable agreement between
a Globus supersficies*, and a plaine superficies*, therefore a Chart both
not expresse that certainty of the premises which is thereby pretended
to be given, for things are best described upon bodies agreeable to
their own form. And whereas in the true nature of the Sphere,
there can be no Parallels described but the East and West courses
only, the rest of the courses being concurred lines, ascendent toward
the Poles, the Meridians all concurring and joyning together in the
Poles, notwithstanding in the Sea Chart all the those courses are descri-
bed as Parallels, without any diversity, alteration, or distinction to
the contraty, whereby the Instrument is apparently faulty: yet it can-
not be denied, but Charts for those courses are to very good purpose
for the Pilots use, and in long courses, be the distance never too far, if
the Pilot return by the same course, whereby in the first he prosec-
uted his voyage his Chart will be without errour, as an Instrument
of very great commodity, but if he return by any other way, then by
that which he went forth, the imperfections of the Chart will then
appear to be very great; especially, if the voyage be long, or the
same be in the North parts of the world, the farther toward the North,
the more imperfect: therefore there is no Instrument answerable to
the Globe, or paradoxall Chart, for all courses and climates whatso-
ever, by whom all declared truth is most plentifully manifested, as
shall herafter at large be declared, but for the coasting of any those, or
Country, or for short voyages, there is no Instrument more conveni-
ent for the Seamans use, then the well described Sea Chart.
What is the use of the Sea Chart.
By the directions of the Sea Chart the skillful Pilot conveyeth his
ship from place to place, by such courses as by the Chart are more
known to him, together with the help of his Compass, or Crosse
Staff, as before is shewed, for the Cross-Staff, the Compass, and the
Chart, are so necessarily joynd together, as that the one may not well
be without the other, in the execution of the practices of Navigation:
for as the Chart shewith the courses, so both the Compass direct the
same, and the Crosse-Staff by every particular observed latitude both
confirme the truth of such courses, and also give the certaine distance
that the Ship hath sayled upon the same.
* the modern term is probably "surface"
And in the use, or understanding of the Sea Chart, there are five
things chiefly to be regarded.
The first is, that Countries, or Geography of the Chart be
known, with every Cape, Promontory, Port, Haven, Bay, Sands,
Roks, and dangers therein contained.
Secondly, that the lines drawn upon the Chart, with their several
properties be likewise understood.
Thirdly, that the latitude of such places as are within the Chart;
be also known, as by the Chart they are expressed.
Fourthly, that you be able to measure the distance between place
and place upon the Chart.
And fiftly, the Seaman must be able by his Chart, to know the true
courses between any Iles, Continents, or Capes whatsoever: for by
these five diversities, the Chart is to be used in the skil of Navigation.
How is the latitude of places knowne by the Chart.
The latitude is thus found by the Chart, upon the place, whose lati-
tude you desire to know, set one foot of your Compasses, then stretch
the other foot to the next East and West line (for that line is your Di
rector) keeping that foot still upon the same line, move your hand and
Compasses East, or West, as occasion requireth, untill you bring the
Compasses to the graduated Meridian, and there that foot of the Com-
passes which stood upon the place, whose latitude you would know,
both shew the latitude of the same place.
How is the course between place and place knowne ?
When there are two places assigned, the course between which you
desire to know, set one foot of your Compasses upon of the
places, then by discretion consider the lines that lead toward the other
place, stretching the foot of the Compasses to one of those lines,
and to that part of the line which is nearest to you, keeping that foot
still upon the same line, move your hand and Compasses toward the
other place, and see whether the other foot of the Compasses that stood
upon the other place, doe by this direction touch the second place, which
if it doe, then that line whereupon you kept the one foot of your Com-
passes, is the course between those places: if it touch not the place,
you must by discretion search untill you finde a line, whereupon keep-
ing the one foot of the Compasses, will lead the other foot directly from
the one place to the other, for that is the course between those two
How is the distance of places found upon the Chart ?
If the places be not farre asuder, stretch a paire of Compasses be-
tween them, setting the one foot of the Compasses upon one of the
places, and the other upon the other place, then not altering the Com-
( here are contained 6 pages of Tables before the text continues )
( Nov, Dec, Sept, Oct. July, Aug. )
passes, set them upon the graduated Meridian of your Chart, and al-
lowing 20 leagues for every degree that is contained between the two
feet of your Compasses, the distance desired is thereby known: if be-
tween the places there be 5 degrees, then they are 100 leagues asun-
der, &c. But if the distance between the places be so great as that the
Compasses cannot reach between them, then take out 5 degrees with
your Compasses, which is 100 leagues, & therewith you may measure
the distance as practice will teach you. There is also in every Chart a
scale of leagues laid down, whereby you may measure distances, as is
How doth the Pilot order these matters, thereby to conduct his
Ship form place to place ?
The Pilot in execution of this part of Navigation, doth with careful
regard, consider three especial things, wherupon the full practixes are
1. Of which the first is, the good observation of his latitude, which
how it may be knowne is before sufficiently expended.
2. The second is a carefull regard of his steredge, with diligent
examination of the truth of his Compasse, that it be without variation
or other impediments.
3. And the third is a carefull consideration of the number of leagues,
that the Ship sayleth in every hour or watch, to the neerest estimation
that possibly he can give, for any two th these three practices being truly
given, the third is thereby likewise knowne.
As by the Corse and height the distance is manifested, by the distance
and Crose the height is knowne: by the height and distance the Corse is
given, of which three things the Pilot hath only his height in certain:
the Corse is somewhat doubtfull, and the distance is but barely supposed,
notwithstanding from his altitude and Corse he concludeth the truth of
his practise, proceeding in his sort.
First, he considereth in what latitude the place standeth from whence
he shapeth his Corse, which for an example shall be the Lysart Standing*
in 50 degrees of Septentrional latitude, then directing his Corse S.W.
sayleth 3 or 4 daies or longer in such thick weather, as that he is not
to make any observation of the Poles altitude, in which time he omit-
eth not to kep an axxompt how many leagues the Ship hath sailed upon
that Corse as neer as he can guesse, which number of leagues in this ex-
ample shall be 100 according to his judgement: then having conve-
nient weather, he observeth in what latitude he is, and findeth himself
to be in 47 degrees, now with his Compasses he taketh the distance of
100 leagues, which is the quantity of the Ships run by his supposition,
and then setting one foot of the Compasses upon the Lysart, which is
the place from whence he began his Corse, and directly South West
from the same he setteth the other point of the Compasses, by the directi-
on of another pair of Compasses, in such sort as Corses are found, and
there he maketh a prick for the place of his Ships being, according to
his reckoning and Corse.
And now searching whether it do agree with his height, (for the
right, Corse, and distance must also agree together) he findeth that his
prick standeth in 46 degrees, 26 minutes, but it should stand in 47 de-
grees to agree with his observation. Therefore perceiving that he hath
given the Ship too much way, he bringeth his Corse and observed alti-
tude to agree and then he seeth that his ship hath sailed but 85 leagues,
and there he layeth down a prick for the true place of his ships being, ac-
cording to his Corse and latitude, for so by his Corse and height he findeth
the truth of his distance, and reproveth his supposed accompt to the 15
leagues too much: and after this sort he proceedeth from place to place,
until he arrive unto his desired Port: which is a conclusion infallible,
if there be no other impediments, (whereof there hath not being good
consideration had) which msy breed error, for from such negligence
there may arise many inconveniences.
What may those impediments be ?
By experience at the Sea we find many impediments that so disturb
the expected conclusion of our practice, as that they agree not with the
true positions of Art. For, First it is a matter not common to have the
wind so beneficial as that a Ship may sail therby, between any 2 assign-
ed places upon the direct corse, but that by the contrariety of winds, she
may be constrained to travers upon all points of the Compass, the na-
ture whereof I have before sufficiently expressed.
Secondly, Although the wind may be in some sort favour, yet the ship
may have such a Leeward condition, as that she may make her way 2 or
3 points from her caping.
Thirdly, The Sterage may be so disorderly handled, as that thereby
the Pilot may be abused.
And lastly, The Compass may be so varied, as that the Pilot may
likewise thereby be drawn into errour, at all which things, and many
moe, as the nature of his Sayling, whether before the wind, quartering,
or by a bowling, or whether with lofty or low sails, with the benefits or
hinderances of the Sea, tydegates, streams, and forced let therefore, &c.
of all which things (I say) the skilful Pilot must have careful consi-
deration, which are better learned by practice, than taught by pen, for
it is not possible that any man can be a good and sufficinet Pilot or skil-
ful Seaman, but by painful and diligent practice, with the assistance
of Art, whereby the famous Pilot may be esteemed worthy of his Pro-
fession as a Member meet for the Common weale.
And now having sufficiently shewed you the ordering of your Chart,
for the execution of the skill of Navigation, and being also desirous that
you should effectually understand the full nature & use of the same: I
think it good by a few questions to give you an occasion to exercise your
self, in the perfect accomplishment of such conclusions as are by this
excellent and commodious instrument to be performed.
Necessary Questions for the better understanding of the
commodious use of the Chart.
1. Q. If I sail 70 leagues upon the Southwest course, I demand
how many degrees I shall lay or depress the Pole ?
A. The difference will be 2 degrees, 30 minutes.
2. Q. If in sayling West Northwest I raise the Pole 3 degrees, 30
minutes, I demand how many leagues I have sailed ?
A. The distance sailed is 180 leagues.
3. Q. If in sayling 180 leagues between West and North, I raise
the Pole 3 degrees, I demand upon what course I have sayled, and how
far I am from the Meridian from whence I began that course ?
A. The Corse sailed is Northweat by West, and the distance from
the Meridian is 90 leagues.
4. Q. If in sayling 154 leagues I be 80 leagues West from the Me-
ridian form whence I began my Corse, I demand upon what point of
the Compass I have sailed, and how much I have raised the Pole ?
A. The Corse is Northweat by North, and the Pole is raised 6 de
5. Q. If I sail Northwest until I be 50 leagues from the Meridian,
where I began my Corse: I demand how many leagues I have sailed,
and how much the Pole is raised ?
A. The distance sailed is 71 leagues, and the Pole is raised 2 de-
grees, 32 minutes.
6. Q. If in sayling W.N.W. I do in 30 hours raise 2 degrees, how
many degrees should I have raided the Pole if the same motion had
been North and by West ?
A. You should have raised 5 degrees.
7. Q. A Ship sayling towards the West, for every 80 leagues that
she sayleth in her Corse, she departeth from the Meridian from whence
she began the same Corse 45 leagues, I demand upon what point of the
Compass, and how many leagues she hath sayled, in raising the Pole
5 degrees ?
A. She hath sayled Northwest by North 120 leagues.
8. Q. A Pilot sayling toward the West 100 leagues, hath forgot-
ten his Corse, yet thus he knoweth that if he had sayled upon such
a corse, as that in 160 leagues sayling he would have raised the Pole
3 degrees, he should then have been twice as far from the Meridian
as now he is, and should also have 1/2 degrees further to the Northward
then he now is, I would now know what corse he hath sayled, how ma-
ny leagues, and how far he is separated from the Meridian, from
whence he began the said corse ?
8. A. She hath sayled 88 leagues Northwest by West, & is 73 leagues
from the Meridian nearest.
9. Q. Two ships departing from one place, the one sayling 145
leagues toward the west, hath raised the Pole 4 degrees, and the o-
ther hath the Pole 7 degrees, and is 95 leagues West from the
Meridian of the place from whence he began his corse, I demand by
what corse the said ship hath sayled, and how far they be asunder, and by
what corse may they meet ?
A. The first ship hath sayled Northwest by west, the second hath
sayled Northwest by North 170 leagues, they are asunder 65 leagues,
and the corse between them is North northeast, and South southwest.
10.Q. Two ships sayling from one place, the one in sayling 180
leagues, is to the Eastward of the Meridian where he began his corse
150 leagues, I demand upon what corse, & how many leagues the other
ship shal sayl, to bring himself 50 leagues N. by W. from the first Ship ?
A. The first ship hath sayled N.E. by E. and hath raised the Pole 5
degrees, the second ship must sayle Northeast by North 237 leagues.
sers of this excellent Art of Sayling, that they do not only by their
Although it may seem (to some that every expert in
Navigation) that these Questions are needlesse, and
without use, being so plain as not deserving in this
sort to be published, nothwithstanding that their Opi-
nion, I do in friendly courtesie advise all young Practi-
Charts prove the truth of these answerd Questions, but also endea-
vor themselves to propound divers others sorts of Questions, and
in seeking their Answers to enter into the Reason thereof: for by
such exercise, the young beginner shall understand the substantial
grounds of his Chart, and grow perfect therein: for whose ease
and furtherance only, I have at this present Published this brief
Treatise of Navigation, knowing that the expert Pilot is not un-
furnished of these Principles, but every little help doth greatly fur-
ther in every beginning: And therefore for the further benefit of
the Practicer, I have hereunto annexed a particular Sea Chart of our
Channel, commonly called the Sleve, by which all that is before
spoken as touching the use of the Chart, may be practiced, wherein
the depths of the Channel are truely laid down: being an Instru-
ment most commodious and necessary for such as seek the Chan-
nel comming out of the Ocean Sea, much of it is from my own
practice, the rest from Pilots of very good sufficiency & I have found
great certainty by the use of this Chart, for by the Altitude and
depth I have not at no time missed the true notice of my Ships be-
ing, which (through Gods merciful favour) by my lands falls I
have fourd always to be without terrour, therefore have it not in
light regard, for it will give you great evidence, and is worthy to
be kept as a special jewel for the Seamans use, be he never so ex-
And thus having sufficiently expressed all the practices appertain-
ing to the skill of Horizontal Navigation, which kind of Sayling is
now of the greatest sort only practised; I think it good for your
better memory, briefly to report that which before is spoken as
touching this kind of Navigation, and withal it will not be amisse
to shew you after what sort I have been accustomed to keep my Ac-
compts in my practises of Sayling, which you shall find to be very
sure, plain, and easie, whereby you may at all times examine what
is past, and to reform the causes laid down upon the Chart, if by
chance there should be any errour be committed. And so concluding
this part of Navigation, will in the next Treatise make known unto
you the use of the Globe, such uses I mean as Seaman may
practice in his Voyages, and that are most necessary for his know-
A Table shewing the Order how the Seamen may keep his Ac-
compts, whereby he may at all times distinctly examine his
former practises, for in every 24 hours, which is from noon to noon,
he doth not only lay down his Latitude, which the Corse and Leagues,
but also how the Wind hath blown in the same time.
The first Colume is the months and dayes of the same; the seoonc
is the observed Altitude, the third is the Horizontal Corse or mo-
ton of the Ship, the fourth the number of Leagues that the Ship hath
sayled, the fifth is a space wherein must be noted, by what Wind
those things have been performed: and the next great space is to lay
down any brief Discourse for your memory.
| ANNO 1593 | The 13 of March |
| | cape S Augujiiu in |
|Month and | | | | | Brasil, being 16 |
|dayes of the| Longi- | Corse. |Leag-| Wind | leagues East from |
|Month. | tude| | us | | me, I began this |
| | G. M. | | | | accompt. |
| March. 24 | 7 | 30 | N.N.E. | 25 | East | |
| |---|----|-----------|----|----------| Compasse varied 9 |
| 25 | 5 | 44 | N.b E.nor | 30 | E.b.N | degrees the South |
| |---|----|-----------|----|----------| |
| 26 | 4 | 1 | N.b.N. | 35 | E.b.N | point windward |
| |---|----|-----------|----|----------| |
| 27 | 2 | 49 | N. | 24 | E.b.N | Compasse variat 8 |
| |---|----|-----------|----|----------| degrees, the South |
| 28 | 1 | 31 | N.easterly| 26 | E.b.N. | points windward. |
| |---|----|-----------|----|----------| |
| 29 | 1 | 4 | N.N.W. | 9 | N.E. | |
| |---|----|-----------|----|----------| Compasse varied 6. |
| Aprill. 31 | 0 | 0 | N.b.W. | 21 | E.N.E. | deg. 40.min. the |
| |---|----|-----------|----|----------| South point west- |
| 4 | 0 | 39 | N.W.b.N | 15 | N.E. | ward. |
| |---|----|-----------|----|----------| |
| 7 | 1 | 53 | N.N.W. | 28 | N.E. | Observation, the |
| |---|----|-----------|----|----------| Pole Artick above |
| 9 | 3 | 5 | N.W.b.N | 20 | N.e.b.E | the Horizon. |
| |---|----|-----------|----|----------| |
| 10 | 4 | 5 | N.W.b.N. | 22 | N.e. | |
| |---|----|-----------|----|----------| |
| 11 | 4 | 45 | N.W. | 18 | N.e.b.N | |
| |---|----|-----------|----|----------| |
| 12 | 5 | 16 | N.W. | 14 | N.e.b.N | Compasse varied 9. |
| |---|----|-----------|----|----------| degrees, the North |
| 13 | 6 | 11 | N.W.b.N. | 23 | N.e. | point Eastward. |
| |---|----|-----------|----|----------| |
| 14 | 7 | 16 | N.W.b.N. | 24 | N.e. | |
A brief Repetition of which is before spoken.
There are three kinds of Navigation, Horizontle, Paraboral, and
Sayling upon a great Circle, performed by the Corse and Trabers.
A Corse is the paraboral line, which is described by the Ships motion
upon any point of the Compass.
A Travers is the variety of the Ships motion upon & very alteration
The Compass is an artificial Horizon, by which Corses and Tra-
verses are directed, and containeth 12 points, and a very point contain-
eth 11 1/4 degrees. or 45 minutes, being 1/4 of an hour.
By such quantity of time as the Moon separateth her self from the
Sun, be the like rate of time every tide both one differ from another.
In every hour the tyde altereth two minutes, in every flood 12 min.
and in every ebbe 12 min. and in every day 48 minutes, because that
so is the Moons separation from the Sun: for the Moon doth separate
her self from the Sun, in every day one point and 3 minutes, between
the Change and the Full she is to the Eastwards of the Sun, and then
is her separation, at which time she is before the in respect of her
matural motion but in regard of her violent motion, she is then behind
or abaft the Sun.
Between the Full & Change, she is to the Westward of the Sun, ap-
plying towards the Sun, and then is her application, at w hich time she
is behind or abaft the Sun, in respect of her natural motion, but in con-
sideration of her violent motion, she is then before the Sun.
She hath a violent motion, a natural motion, a slow, swift, and mean
In every 27 degrees and 8 hours, she performeth her natural motion
through the Zodiack.
Between Change and Change there is 29 days, 12 hours, 44 min-
The Solar year consisteth of 12 months, and the Lunar year of
The Moons Age is found by the Epact.
All Instruments used in Navigation, of what shape or form soever
they be, are described or demonstrated upon a Circle, or some por-
tion of a circle, and therefore are of the nature of a Circle.
A Degree is the 360 part of a Circle, how big or little soever the
A Degree is applyed after the 6 several sorts, to the Equator, to the
Meridian, to the Horizon, to the vertical Circle, to Measure, to Time.
Altitude is the diatance, height, or mounting of one theing above another.
The Poles Altitude is the distance between the Pole and the Ho-
rizon, or the position of the Meridian which is contained between the
Pole and Horizon.
The Altitude of the Sun above the Horizon, is that portion of the
vertical circle, which is contained between the Horizon and the Sun.
Latitude, is that arc of Meridian which is contained between the
Parallel of any place and the Equator, or that part of the Meridian
which is included between the Zenith and the Equinoctial.
Longitude is that portion of the Equator contained between the
Meridian of S. Mihels, one of the Iles of the Assores* and the Meridian
of the place whose longitude is desired: the reason why the accompt of
the longitude both begin at this Ile, is because that there the Compass
hath no variety, for the Meridian of this Ile passeth by the poles of the
world, & the poles of the Magnet, being a meridian proper to both poles. **
The Longitude between place and place, is the portion of the Equa-
tor, which is contained between the Meridian of the same places.
Declination is the distance of the Sun, Moon, and Stars, from the
Equinoctical, or that part of the Meridian which passeth by the Center
of any celestial body, and is contained between the same center and the
Hydrography is the description of the Ocean Sea, with all Iles,
Bancks, Rocks, and Sands therein contained, whose limits extend
to the Geographical borders of the earth, ther perfect notice whereof is
the chiefest thing required in a sufficient Pilot, in his excellent practice
Geography is the description of the earth only, whereby the terrestri-
al form in his due situation is given, whose distinction is by moun-
tains, rivers, vallies, cities, and places of fame, without regard of
Circles, Climates, and Zones.
Cosmography is the description of the Heavens, with all that is con-
tained within the circuit of but to the purpose of Navigation, we
must understand Cosmography to be the universal description of the
terrestial Globe, distinguished by all such circles, by which the di-
stinction of the celestial Sphere is understood to be given, with every
Country, Coast, Sea, Harborow, or other place seated in their due
longitude, latitude, zone, and clyme.
The Chart is a special Instrument in Navigation, pretending the
Cosmographical description of the terrestial Globe, by all such lines,
circles, corses, and divisions as are required to the most exquisite skill
The End of the First Book.
* Assores = Azores Islands
** There was a time when it was thought one could find longitude
from magnetic variation.
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