of Miaco in Iapan I questioned with them concerning their shipping and maner of sayling They described all things farre different from ours and shewed that in steade of our Compas they vse a Magneticall Needle of sixe ynches long and longer vpon a pinne in a dish of white China earth filled with water In the bottome whereof they haue two crosse lines for the foure principall windes the rest of the diuisions being reserued to the skill of their Pilots Vpon which report of theirs I made present triall howe a Magneticall Needle would stand in water and found it to proue excellently well not doubting but that many conclusions of importance in Marine affaires will thereby more readily be performed I finde that as the Portugals traueiled in their very first discoueries for the East Indies they got a Pilote of Melinde that brought them from thence in 33. dayes within the sight of Calecute and had euen then in vse the Compas the Carde and the sownding line Ludouicus Vartomannus testifieth that in his voyage from Bornco vnto Giaua the Pilots of those Countreys had the vse of both Compas and Carde and had skill to take direction from the South Pole as ours doe from the North euen in those dayes when it was a very daintie matter for any of our Pilots to haue performed the like being as then possessed with an opinion that the Compas would turne round assoone as euer they came vnder the Equator as some doe yet surmise it would doe vnder the Pole or neere the fantasticall Rocke of the purest Magnes Philander in his annotations vpon Vitruuius sheweth that some men deemed it not a newe but an olde inuention and tooke it to be that Nauticall instrument which is called by Plautus in Trinummo and Mercatore by the name of Vorsoria But this Adrianus Turnebus in no case will allowe affirming it rather to bee a kinde of tackle wherewith they turned their Sayle If of olde time they had not this Instrument it seemeth impossible that euer they could haue performed such voyages as they did And if euer they had it then were it as strange that all memorie thereof should be vtterly suppressed and that Ptolomey had not found some mention thereof made in Marinus Tyrius or other Cosmographers whose workes were extant in his time Experience testifieth that this began to be in common vse about the time that Printing was inuented and the making of Gunnes Both which although they are of very excellent vse and great wonderments to the world yet doeth this farre excell and exceede For all things performed by them are marshalled within the limittes and bounds of humane reason and therefore their causes being knowen their wonder ceaseth But this being incomprehensible vnto humane reason carieth it away captiue vnto the astonishment thereof and leadeth it to the admiration of him whose wisedome comprehendeth all things and distributeth knowledge and vnderstanding among men according to such measure times and meanes as seemeth best vnto himselfe opening the eyes of the blind and giuing vnderstanding to the simple destroying the wisedome of the wise and making the vnderstanding of the prudent for to hide it selfe Considering the fowle abuses and errors that dayly are committed in the making and framing of this worthie Instrument I haue thought good heere briefely to note the faults and therewithall to shew the way how they may bee amended Let no man mistake me I speake not saue onely of ordinarie Compasses being the most that euer I sawe such as are in common vse and are sale-ware for Masters and Pilots What some discreete skilfull men carefully doe prouide for themselues I speake not of First therefore for the most part the Carde of the Flie is negligently diuided not only in the Compas which they ordinarily saile by hauing the 32. common partes but as great negligence may be found in the double Flie for their Compasse of Variation where the vttermost Ring which they make moueable about the ordinary Flie is diuided into degrees and there a degree or two oddes breaketh no square with them The wyers of the Flie are as rudely set together hauing their ends not sitted euen and close as were meete but starting a side eache from other not somuch as filed smoothe but rough euen as they were broken whereby they are also disabled from taking so strong a touch as they would if they were made smoothe For remedie hereof it were good to drawe the ouale lines vpon the Carde of the Flie in such sort that the endes being euen with the circumference of the Flie both the middles and the endes may haue an equall distance from the Center Then according to those lines bow and cut the wyers fitting their endes smoothe and so closely ioyning them that they may both seeme to be but one After that holding them together dippe the endes in a little moulten Tinne or if at the first they be welded together it is the better and with the edge of a dull knife scrape off the Tinne againe asmuch as you can come by which will be all in a maner sauing onely a very little that keepeth the endes together and that will hold them so fast that you may conueniently handle them at your pleasure and fasten them on their place according to your desire But before they be set on let them be touched as abouesaid and being set on their touchings at the ends must be refreshed Thus shall your Flie stand and turne equally vpon his pinne if not in stead of the ordinary dawhing with waxe two or three drops at the most will counterpoyse any swaruing and many times you shall not neede any at all which is most commendable The Capitall is commonly wide from the Center of the Flie and likewise the pinne whereon the Flie standeth from the Center in the bottome of the Boxe both grosse and absurd faultes and yet easie to bee auoyded The glasse that couereth the Boxe is commonly crackeled and snarled by the sides and diuerse times also too little These faults they couer with their thicke border of Rosen but better were it to amend them with a little heede taking The Glasse ought therefore to be somewhat thinne smoothe and of euen thickenesse hauing the edges smoothed on a grinding stone or by some other meanes and made very fitte to the Boxe So shall you neede but little quantitie of Simmond onely to keepe out the ayre which is the better both for the clearer view of the Flie and that your Boxe may hang the steaddier and that will it not doe if your Glasse be much thicker on the one side then on the other or els being too little bee thrust neerer the one side then the other and the voide place filled vp with Rosen according to ordinary custome The Boxe is hanged in two Circles the one within the other hauing the pinnes that they turne on a quarter of a Circle in the one distant from the other But these Circles
Eastwards or Westwards and according to discretion set your Flower de luce as may best fitte the way of your course And therefore if it be most South or North let the longer sides of your Table stand in steade of those partes if it be East or West then name the sides accordingly For example if it be Eastwards Northerly set downe a pricke betokening your Radicall place vpon the West end of the South side if it be any other way set downe your pricke as may be answerable thereunto and placing your Ruler square vpon equal diuisions in the sides East West with the edge thereof touching the said Pricke drawe a line representing the Parallele of the Ships Radicall place and hard by the point or pricke of your Radicall place note the Latitude there of in degrees and minutes Then set the Center corner of your Quadrant vnto the Radicall point eleuating the limbe of the Quadrant aboue the Parallele according to the quantitie of that Angle whereon the Ship made her first way and reckoning in the edge of the Quadrant the leagues of the Ships way at the ende thereof make a pricke as close vnto the edge as may be Lastly fastening your Ruler directly vpon the pricke and square with the sides of East and West drawe a line which shal serue for the Parallele that the Ship at that instant is in And this order of working must from time to time be iterated till at length opportunitie be offered by your Instruments Mathematicall to make an obseruation of Latitude But if it so fall out that the Shippes way doe conteyne moe leagues then there are diuisions in the side of the Quadrant then applying either side of the Ruler close vnto the edge of the Quadrant by that meanes you may pricke downe the number Hauing vpon shift of windes as it happeneth made diuerse Trauerses if you desire to knowe howe the place your Ship is in beareth from your Radicall place which is called the Angle of position and likewise the distance from it as also the Latitude together with the Difference of Longitude when you haue made as yet no obseruation doe after this sort Set the one end of your Ruler where the numbers doe beginne to the Radicall point and directing the other end towards the pricke of your Ships last place cause the edge to lie iust euen vpon it Then reckon howe many diuisions you do finde betweene the two points and so many leagues distance there is If it fall not full vpon a diuision but vpō one of those pricks betweene they signifie English miles Looke howe many diuisions are conteyned betweene the two Paralleles the one of the ships Radicall place and the other of her last place euery twentie of those doe make a degree euery seuerall diuision 3. minutes and euery pricke one minute Moreouer as occasion serueth you may accompt 4. or 5. diuisions for a league or more or lesse yea euery pricke for a league if you finde it requisite as experience in diuers shiftes of windes will shewe you to be most conuenient To knowe howe much the Ships last place doeth differ from his Radicall place in Longitude also the Angle of Position SEt the Ruler square North and South so that the Radicall place may touche the side thereof marking what diuisions the Ruler doeth cut in the North and Southsides Againe set the Ruler in like maner square touching the point of the Ships last place the number of partes conteyned betweene those two places of the Ruler in either of the two sides North or South is the difference of Longitude If the ships last place from the Radicall be Easterly the Longitude is so much encreased if Westerly it is lessened Alwayes haue you respect to the Meridian from whence Longitudes doe beginne to be reckoned that you may expresse the number answerable thereunto Moreouer place your Ruler where the numbers begin at the Radicall point and the side thereof vpon the point of the Ships last place Then apply the Center corner of the Quadrant vnto the Radicall point the Ruler still keeping his place in such sort that the side of the Quadrant doe lie euen with the Ruler Looke howe much of the eleuated limbe aboue the Parallele the Parallele it selfe cutteth off that is the Angle of Position vpon which the last place of the Ship doeth beare from the Radicall places But whenso euer you haue opportunitie to obserue the Latitude drawe your Parallele vpon the Trauerse boorde according thereunto and where the line of the Ships course doeth crosse the Parallele you must conclude that to be the place which your ship was in at the time of your obseruation correcting by that meanes the other Parallele and distāce taken by the dead reckoning so farre forth as it doth differ from this For of those three helpes before specified the Latitude is only certaine The Angle of the Ships way is reasonable good but the dead reckoning is an vncertaine ghesse And if you please to call it a probable coniecture you shal grace it with the vttermost notwithstanding it is admitted into Art for want of better helpes In considering the Angle of the Ships way by all meanes you must haue carefull regard both vnto the Set and the Variation of your Compasse Otherwise assure your selfe you shall make but wide reckonings I haue knowen a very expert Nauigator that making his reckoning without regard of the Variation which for all that he obserued though he did not reckon by it ouershot the way of his Ship 70. leagues in a voyage not of so farre distance as hence to Cape Verde Whereas casting ouer his reckoning with due respect of his Variation he made a perfect good accompt of of the very same voyage Hauing found the place of your Ship in the Trauerse-boorde howe to pricke it in your Carde FOr the conclusions to be performed vpon your Carde it is requisite that you haue a Ruler of some fine wood made very thinne of an inche a halfe broad and of sufficient length also a Quadrant like vnto the former sauing that his two sides must haue their diuisions agreeable to the Scale of leagues expressed in your Carde and finally 2. paire of Compasses Being furnished with these seeke out your Radicall place from whence you did proceede Apply the Cēter-corner of your Quadrant vnto it his limbe respecting the way answerable to the Angle of position in your Trauerse-boorde Set one foote of your Compasse vpon any Parallele of conuenient distance from it on which side it skilleth not reaching the other precisely vnto it in the nearest distance Then remoue one foote vpon that Parallele the other keeping his scantling vntill the diuision of the Angle of Position in the limbe the point of the other foote doe meete exactly together the Center-corner stil abiding in his place but mouing the limbe to or fro and likewise the Compas as before I specified til they meete Last of
A B. from whence the degrees of the Quadrant beginne a line precisely equall vnto a namely D F. And from the points D and F. to the Semidiameter A C. raise two Paralleles D E. and F G. Againe from F. toward B. at a distance conuenient take the second line K H. equall vnto a. And from the points H K. rayse other Paralleles H I. and K L. equidistant to the former Afterwards applying the one ende of your Ruler to the Center A. and the other to euery the degrees of the Quadrant B C. drawe lines athwart betweene the Paralleles aforesaid so shall all the lines thus drawen cōteyned betweene the Paralleles be the degrees of the Meridian sought for taking their several Denominations of their correspondent degrees in the Quadrant as by the figure here ensuing is manifest Of what sort soeuer your Cardes be you must alwayes remember that the knowledge of the vse of the Globe must be a moderator vnto them and that thereby you shall still become master ouer your Card to espie and amend his faults whereas otherwise you shall be mastered by your Cards blindly embracing their errors By meanes hereof it was that the famous Nauigators of the World performed their discoueries renowmed voyages hauing no maner of Cardes to sayle by And an easie matter it is for a man that already hath ordinary skill and practise in sayling by vsuall Cardes to learne in one fourthnight so much of the vse of the Globe that vpon his obseruations he may either keepe or change his Points for his best aduantage And of any places whose Longitudes or Latitudes are knowen may tell without any Carde vpon what point they lie and howe farre they are distant from you Also vpon what Point they lie each from other the distance betweene them with diuerse other things that are necessarie and helde for rareties in that facultie For in very many of them Enuie doth so reigne that almost euery one keepeth his owne knowledge to himselfe without imparting it vnto others whereas they should all profite a great deale more if they would communicate their knowledges one with an other for the publique benefite But in so much as eache one affecteth to be singular disdayning the knowledge of others they haue farre lesse knowledge amōg them all then otherwise they might haue for of necessitie many mens practises must cōcurre to make experimental knowledge exact It were greatly to be wished that many of them might be founde so well minded towardes their owne trade as was that notable Pilot Steuen Burrowes who for his skill industrie and performance may iustly be reckoned among the chiefe of our Nation and of the world also if we respect that only in stead of al which he worthily atchieued in the first Moscouian discouerie by the Scythian Sea who if he had bin employed one Sommer more againe towardes the Riuer of Obbe I doubt not but proceeding with his former successe he would haue performed more in that Sommer for trial of a Passage any or none that way vnto Catthay then for the space of these 40. yeeres all Christendome hath done besides not hauing asitseemeth added vnto his 40. leagues of good discouerie euer since The good mind he bare towards his profession he testified herein that by his very earnest meanes he procured that learned and easie Treatise of Martine Curteise concerning the Arte of Nauigation to be translated into our English tongue The which doubtles hath giuen great light vnto all of skil in that faculty that euer were since of our Nation And is more almost then all our Nauigators haue holpen the Arte of Nauigation withall besides A great helpe also would it be for the furtherance of skill if those that are practisers in that Arte and such as are Students of the Mathematikes might often conferre together For except there be a vniting of knowledge with practise there can be nothing excellent Idle knowledge without practise ignorant practise without knowledge serue vnto small purpose But certaine it is that all the good partes which may be wished for or aymed at shall neuer absolutely concurre in one man And therefore if there be but some conuenient mixture of them in any that party is to be esteemed For although many things appertayning to Nauigatiō may be learned taught by rules of Arte yet some necessarie points without which all the rest is nothing are beyond the compasse of Arte As for a man to be of a ready and valiant mind to handle and order those things that are within the reache of his knowledge with dexteritie vpon euery present occasion These and such like are iustly termed the giftes of God For although all things tearmed by Arte are the giftes of God sith euen Arte it selfe is giuen by God who is the Authour and fountaine of all knowledge yet these are tearmed his giftes more peculiarly because the other are giuen by meanes and these without meanes Suppose that a man haue all the knowledge that may be wished for be notwithstanding faint hearted his wits as they say to seeke whē he hath most neede of them his knowledge will ayde him very little Againe if he be of neuer so bolda courage want discretion knowledge iudgement he is very vnfit for the gouernement of a Ship But if such a one be also as most cōmonly they are wilfull taking it for a glorie to be foolehardie this is as great a mischiefe as all other dangers of the Sea if they were all set together Where therefore boldnes of courage directed moderated by discretion iudgement also a body enhabled to brooke the Seas are matched with a willing mind vnto Marine affaires endued with the feare of God wheresoeuer I say these speciall giftes of God are to be found there the ornaments of Arte as necessary additaments will alwayes most effectually take place are most easily attained vnto But where those former at the least in some comperent measure are not al the rest is vanitie It is euen a most irkesome and wofull sight to behold a company of courageous yong Gentlemen to be led on blindfolded as it were in marine actions by such as haue no feare of God before their eyes and many times by those that are very ignorant of almost any thing that good is if any thing might be accompted good where the feare of God is not but onely can tell of their owne experience howe they haue dissimboched from Terra Stolida making their voyage toward the Isle of Pickery gracing themselues as they suppose with swearing and staring and wishly lookes A few such monsters hauing the chiefe gouernement in Ships and voyages are a great deale more dangerous then all the monsters in the Sea And for euery one that is bereft of life by these a hundred at the least are destroyed by the other The serious consideration of these things haue occasioned me of a friendly mind and entire good will wherein toward your profession I wil giue place vnto no man liuing to admonish you of these points which I haue thought necessary Beseeching Almighty God who is the Lord both of Sea dry Land by his holy Spirit of true wisedome to gouerne direct you in all your actions that employing your diligent endeuour in your Arte in his feare and calling vpon him in the time of trouble he may heare and deliuer you from all your distresses And that being deliuered you may accordingly glorifie him yeelding praise and thankes for his mercies before the sonnes of men Let Staffe Carde Compasse Ship and Skill Depend vpon Gods blessed will * * * Cap. 1. Cap. ◠Cap. 3. Cap. 4. Cap. 5. Cap. 6. Cap. 7. Cap. 8. Cap. 1. Cap. 2. Cap. 3. Cap. 4. Cap. 5. Cap. 6. Cap. 7. Cap. 8. Cap. 9. Cap. 10. Cap. 11. Cap. 12. Cap. 13. Cap. 14. Cap. 15. Cap. 16. Cap. 17. Cap. 1. Cap. 2 Cap. 3. Cap. 4. Cap. 5. Cap. 6. Cap. 7.
or Degree the Needle is at And then working in all respects as before I declared the Variation is made knowen vnto you If you haue a Crosse-needle well made it will serue in steade of the Perpendicle better then the Perpendicle it selfe In as much as it is not subiect to the whirling of the winde but is quiet therefrom being defended by the Glasse close symmond round about The taking of the height of the Sunne at Sea PLace the Verticall vpon his handle the limbe towards you and his perpendicular side ouer against you and turning your backe towards the Sunne keepe the two sights of the Directory euen with the parting of the water and the Element ouer right against you Moue also the sight Ruler of the Verticall vp or downe till at one instant you may see both the Sunne-beame through the vpper sight to fall vpon his due place in the neather and ioyntly therewithall the parting of the water and Element Then haue you the degrees minutes of the sunnes height by meanes of the Proportionall Quadrant as heretofore is specified This may in like maner be performed by looking toward the Horizon directly vnder the Sunne placing the Perpendicular side towardes you and the limbe from you and thrusting the Directory with his long sights from you or else drawing it towards you as you may most conueniently discerne the sunne-beame of the vpper sight to be vpon his iust place in the neather For the better effecting whereof it is requisite to haue a third square sight forked on the neather side with a couple of small peakes to be placed the one on the one side and the other on the other side of the Center of the sight Ruler ready to be taken off or on and hauing a little marke with two Crosse-lines of equall distance to the holes of the other two sights and the Fiduciall line To the end that this third sight being fastened right ouer the Center of the sight Ruler with his lower edge somewhat aslope and not at right angles with the Fiducial line you may the more easily discerne by meanes of the said marke when the sunne-beame hath perced the other two sights aboue And then haue you all things as before Wherefore if two obseruations be made together the one from the Sunne and the other towards it and both these agree in one The whole Operation must needes bee exact and without any doubt of error The ordinary staues so that they be well made and good regard had to the Eccentricitie of the eye be very commodious for so much as they can performe which cannot be much aboue 45. degrees because the eye at one viewe is scarce capable of a larger Angle And therefore in great Altitudes of the Sunne they are vnseruiceable the Astrolabe or searing as some terme it comming in place of them And yet the vse of this also in a hie Sea is very vncertaine But with the Instrument that nowe is described vnto you you may take the height of the Sunne at what angle so euer yea although he be verticall Herein this and the staffe agree that both of them haue a speciall respect to the Horizon but they differ in the danger of the Eccentricitie of the eye whereunto the staffe is subiect but this is not so and neuer requireth any Angle in the eye of the Obseruer that shall exceede the capacitie of 20. degrees Somewhat also might here haue beene added of the diuerse placing of the sights vpon the Directorie but for breuitie sake I referre it to the consideration and choise of the Practiser vpon diligent triall thereof The Hemisphere The Scope of this Treatise TWo things there are in euery Instrument of speciall and most necessarie consideration the one the body as it were and substance of it the other the ende or purpose whereunto it serues The body or substāce of euery Instrument and namely of this whereof nowe wee treate I call the Materiall partes of which it consists together with their peculiar formes such as whereby that end may be best atteyned best I meane with the greatest both certeintie and facilitie possible The purpose or end I terme the manifold commodities to be reaped thereby and especially in this Instrument the singuler most pleasant and profitable vses whereunto it is and may be applied All which fully to discourse of would require farre more leysure then either my vocation or other many affaires of importance may permit me I shall therefore sufficiently content my selfe in this behalfe if first I deliuer to the skilfuller and more industrious sort a briefe and perfect viewe of the Instrument by a particular and euident description to the eye of all the Members thereof which once conceaued the thing of it selfe without any further words of mine wil most easily and readily vnto them declare his owne vse from point to point in Astronomie Geographie Nauigation and such like excellent faculties But because that the Nauigatour is the man for whose sake chiefely I haue taken these paines And among those of that trade the most part are though commendably perhaps furnished with experience yet but weakely assisted with fitte Instruments and of themselues for want of some contemplatiue knowledge Mathematicall not able either to inuent fitter or to reforme and better those that presently they vse I thought it requisite for them together with the description and frame of the Instrument to adde in the second place some fewe principall admonitions concerning the seuerall most necessarie vses thereof vpon sea or land And in so doing I wil leaue many things to the Readers owne ingenious practise Many also will I omit or rather presuppose as already knowen namely what a Pole is an Equinoctiall a Meridian c. being such as are the first Principles of this Arte wherewith euery man is commonly acquainted and by diuerse in our owne vulgar speache haue in the largest maner oftentimes be handled The names of all the partes of the Hemisphere NOwe if any desire to knowe what this Hemisphere is by it selfe and so must he first if hee will orderly proceede to the getting of perfect knowledge in the vse for no man can well handle an Instrument that he knoweth not a generall declaration of the partes accompanied with their Mechanicall description and a briefe comparing of them with the Globe may so throughly suffice as more herein is not to be required There are therefore in this Instrument two sides to be considered the one more principall which I terme the Face the other lesse which I cal the Backe The Face consisteth of whole Circles and halfe Circles The whole Circles are two in nūber whereof the one being the Base as it were of all the Instrument and immoueable is the fixed Meridian because that turne most commonly it serueth the other moueable I call the Deferent for that it carieth vp downe vpon and in it selfe according to any greater or lesser Eleuation or Latitude
marine trades should be ayding vnto those Faculties whereby the greatest part of their well gotten goodes doeth accrewe vnto them And especially that honorable Citie which is not onely made riche but by the meanes of Nauigation is growē famous also throughout the whole World As therefore I vnfainedly acknowledge that in diuers good respectes no one Citie of the whole Earth is comparable vnto it so doe I heartely wish an increase in all commendable actions among which this was none of the least and not a decrease The rather sith the augmentour of the publique benefite in that behalfe shall thereby highly commend his owne true loue towards his Citie and Countrey vnto all Posteritie and become more renowmed by such actions then by any painted glorious Tombe or the like kinde of monuments The onely good methode of teaching and learning Cosmography after a fewe principles of Geometry and Arithmetike first knowen is to beginne with the Celestiall Globe and to be perfect therein before you deale with the Terrestriall for this dependeth on that and the former being once reasonably vnderstoode the other is not two dayes worke After you haue thus receaued a sufficient impression of the Globe wherevnto all true Mappes and Cardes haue a necessarie reference then will the consideration of them become exceeding pleasant and easie vnto you but neuer before This I mention because I haue heard ere nowe of certaine Teachers that vndertaking men of good habilitie to be instructed by them haue beene a great while about a little spending the time about diuerse pretie particular toyes which full easely would haue beene knowen of themselues without any teaching if they had taken the course that I speake off But such imitate ill disposed Surgeons which loue to protract a cure of purpose to sucke the more gaine therefrom Mappes and Cardes of the Globe of the Earth are of three sortes most vsuall distinguished by their seuerall kindes of Meridians and Paralleles The first hath his Meridians and Paralleles described by Circular lines And among those I take that manner of Proiection which Rumoldus Mercator hath vsed proposed long before by Orontius in his Frenche Cosmography as I haue heard to be of all other the very best hauing the Meridians and Paralleles drawen according to the Mater of Gemma Frisius generall Astrolabe The reason that I so greatly like of this is for that the proiection is very Regular and therein the natiue Geographicall description may neerest of all others obteyne their due situation An other sort there is wherein the Globe of the Earth is diuided in two Hemispheres the Center in both of them being one of the Poles and the Circumference the Equator In this the Meridians are streight lines drawen from the Poles vnto the Equator and the Paralleles are Circles These Paralleles may be described after two wayes The one enlarging the landes described towardes the Equator the other towardes the Poles The former is thus delineated Set the one end of a Ruler vpon the ende of one of the Diameters or Meridians aforesaide and the other part of the Ruler 90. degrees from that And keeping the former ende fixed vpon his place remooue the other to euery one or fifth or tenth degree of the next Quadrant till your Ruler passing through the Pole becommeth all one with the same Diameter noting continually in the Semidiameter of 90. degrees distance whence you first beganne to moue your Ruler where it cutteth the saide Semidiameter Then placing one foote of the Compasse vpon the Center or Pole the other vpon any of those diuisions of the Semidiameter describe a Circle which shall be a Parallele answerable to that diuision And so may you drawe as many or fewe as you thinke conuenient The other is thus described Beginne at the ende of any Semidiameter where it toucheth the Equator and numbring still equall degrees on eache side thereof marke what intersections your Ruler applyed vnto them maketh in that Semidiameter Then may you drawe the Paralleles here also euen as before The former of these two is represented vnto you by the figure A. the later by the figure B. This kinde of Proiection serueth most aptly to expresse in a Carde the Spirall course of a Ship which some terme Paradoxall But whether of these names being both as yet strangers shall best deserue to bee freedenized I leaue to other mens iudgements Onely I say Paradoxall is beside the purpose and astonisheth with an emptie sound but Spirall apperteineth directly to the matter and declareth the true essence of the thing signified The third sort of Cardes haue both their Meridians and Paralleles of streight lines equidistant and these onely are in ordinarie vse with Saylers Of these I neede not write any thing they are so commonly knowen and their imperfections in long voyages so manifest though in short they may well serue the turnes And yet I cannot here conceale one great secrete concerning these Cardes namely that there is a certaine draught of them very Artificiall and regular which being well vnderstoode redresseth the errours of the other and as farre as I canne discerne will so satisfie the Nauigators expectation as no Carde hitherto inuented was euer comparable vnto it neither as I thinke any that shalbe hereafter wil in al respects surpasse it Although for the Geographicall descriptions they may and must alter from time to time as newer discoueries by light of trueth shall make them better knowen vnto vs. This manner of Carde hath beene publiquely extant in print these thirtie yeeres at least but a cloude as it were and thicke myste of ignorance doth keepe it hitherto concealed And so much the more because some who were reckoned for men of good knowledge haue by glauncing speaches but neuer by any one reason of moment gone about what they coulde to disgrace it The Carde which I meane is the same that was set foorth by the excellent Cosmograpber Gerardus Mercator in shewe resembling ordinarie Sea Cardes saue that the degrees of the Meridians in it doe proportionally encrease from the Equator toward eache Pole vpon good reason and firme Demonstration thereby shewing the true Position of any one place in respect of an other which the vsuall Cardes in a farre distance cannot doe being yet the very principall point that the Nauigator desireth For the better vnderstanding and making of Sea Cardes of that sort I haue here immediatly ensewing set downe a Demonstration which I obteined of a friende of mine of like profession vnto my selfe euidently shewing the proportionall encreasing of those degrees wherein consisteth the excellencie of that Carde First determine the degree of the Equator in respect whereof you woulde frame the Meridian of your Carde for example the little line a. Next describe the Quadrant of a Circle so large that it may perfectly and distinctly receaue euery of the vsuall 90. degrees into which it must be diuided Then from the Centre A. towarde B. take in the Semidiameter
themselues cannot denie but being ouerpestered with enuie Vouchsafe therefore mine Honourable good Lord of your noble disposition fauourably to accept this small Treatise such as it is which of duetie and good will is offered vnto you protecting it so farre foorth and no further then the trueth of demonstration and commodiousnesse of the conclusions shall deserue And thus beseeching the Almightie to blesse your Lordship to encrease his good giftes in you and to prosper all your Honourable affaires I commend your Lordship and al yours in my humble and heartie prayers vnto the protection of him from whom all good giftes doe descend and with whom there is no variablenesse nor any shadowe of change but yesterday to day and is the same for euer Your Honorable Lordships in all duetie to be commanded VVilliam Barlowe Lectori S. PRaesulis eximij gnatus multisque verendis Patribus affinis pastor ipse pius Hunc foetum peperit quem si tu candide lector Excipias gremio suauis amansque tuo Dentibus haud metuet Criticorum rodier atris Quos tamen vt tener est non metuisse nequit Perlege pertenta bis terque quaterque licebit Quô mage creber eris crescet ille magis At simul hoc vsu matura adoleuerit aetas Iam benè tutus erit viribus ipse suis. To the Reader THis booke was written by a Bishops sonne And by affinitie to many Bishops kinne Himselfe a godly Pastour prayse hath wonne In being diligent to conquer sinne If to thee Reader it may welcome bee The Critickes censure it will feare the lesse For being young from feare it is not free Which otherwise more courage might professe Reade way and try but reade and often trye The rules of skill whereto it doth direct Triall may bring as much authoritie As newnesse hinder it of due respect But yet when time shall to it ripenesse giue It will haue credite of it selfe to liue Uotum Authoris SVmme Deus Coeli terraeque marisque tremende Conditor atque idem rector tersancte patenti Aure fauens facilis mea percipe vota precantis Ex vno veluti gens est humana Noacho Orta vnáque habitans linguâ celebrauit eâdem Te solum verumque Deum Babylonica turris Quum nondum aethereas caput attollebat in auras Sic iterum ô vtinam miseros miseratus in vnum Mortales redigas laceros vt corporis artus Quosfuror ille tuus dispersit ad vltima mundi Coniunctique ineant sancta vt commercia rursus Veliuolis iungas ratibus ceu pontibus ipsos Mobilibus quamuis disiunctos aequore vasto Foelici celeres vento impellente carinas Mirandaque agiles moderanti Pyxide clauos Inprimis tuus ille tuus qui cuncta gubernat Spiritus aspiret placidus Sic lampade diâ Verbo Euangelij toto noscaris in orbe F. N. O God whose power heauen earth sea declare Which being by thy word thy word obey And in their workes which Natures called are Worke but that will of thine which all doth sway Hearken O hearken for thy Christ his sake Vnto the prayer which in heart I make Looke downe with mercie from thy mercie-seate Vpon man-kinde dispersed here and there From Noahs familie which grewe so greate For at the first all but one people were Which but one law which but one language knew One God alone to serue God onely true As yet mans heart did seeke no name of prayse In stately towers which threaten might the skie When pride began great Babel for to rayse Speach was confounded with varietie Since then deuided tongues deuided heartes By sea and land into a thousand partes Yet since thy Spirit of true vnitie In clouen tongues did on Apostles sitte That so thy cursing might a blessing be And clouen tongues deuided people knitte Let that thy Spirit breathe in euery place That all may know the Gospel of thy grace And since the Sea doth some so farre deuide That they may seeme an other world to bee Teach vs our Ships like horses so to ride That we may meete in one and all in thee And as the Needle doth the North repect So all in Christ may onely thee affect A briefe discourse of the Sayling Compasse in generall THE merueilous and diuine Instrument called the Sayling Compasse being one of the greatest wonders that this World hath is a Circle diuided commonly into 32. partes tearmed by our Seamen Windes Rumbes or Points of Compasse which Circle by the touch of the Loadestone sheweth the aforesaid diuisions in all Horisons betweene the Poles according to one and the selfe same perpetuall position in respect of the true points of North and South in euery Horison This Circle is commonly described vpon Pastbord of 5. 6. 7. or 8. inches diameter And hath sometimes subdiuisions with the relation to the 32. and sometimes hath the ordinarie diuision of Circles namely 360. In the Center of this Circle is fastened a little Diamond as it were or a Capitall as some call it of Latten being cinquebored the point thereof appearing a conuenient space aboue the Circle and the hollowed part downeward to be placed vpon the pinne In the bottome of this Circle are glewed two wyars about ¼ longer then the Diameter bended proportionally the one toward the other in the forme of a loope so that the endes ioyne close and euen together in the circumference and the Circle in this maner finished is named the Flie of the Compasse The boxe wherein this Flie is placed must bee couered with cleare glasse made close round about with waxe mingled with Rosen or some other kind of Simmond The bottome of this boxe is to be taken off and on as occasion shall serue in the Center whereof standeth the pinne of Latten of a reasonable height for the Flie to haue sufficient scope This boxe is to be hanged in two Circles of Latten within an other greater Boxe that the Flie which way soeuer the Ship swayeth may alwayes stand vpon his pinne parallele to the Horizon to which end they fasten a piece of Lead to the bottome of the lesser boxe As for the touching of the wyars of the Flie with the Loade-stone I would wish it to be perfourmed after this sort First of all haue a great care of the goodnesse the quantitie and the forme of the Stone for if he be neuer so good and very small therewith he can giue but small force vnto the Compasse And againe though he be neuer so great yet if he be of base qualitie his Touche can be but faint An ouall forme or somewhat longer reteining a like proportion from the middle to each end is very good Alwayes prouided that the length of the Stone lie according to his owne line of North and South for a stone of this forme giueth foorth his vertue in the Touche a great deale more forcibly then it can if by reason of the euil shape thereof his force in himselfe be confusedly
dispersed and not ioyntly directed to his due points The wyers before they bee touched ought to bee polished and made very cleane and fitted vnto the Flie and then touched after this maner With the North end of the Stone presse each wyer beginning at the middle and so along vnto that ende that you would haue turne Southerly And with the South end of the Stone doe the like from the middle of eache wyer vnto the ende that you would haue turne Northerly Then glewe them in such sort that the Flie may stand equally vpon his pinne hauing both the North and South endes of the wyers vncouered that their Touche may be refreshed as occasion shall require After all this is accomplished that the Instrument thus furnished may truely performe his office there must iust regard be had of the Variation as also of the diuerse Set of the Compasse And likewise that it be not placed neare any Loade-stone yron or steele By the Variation is vnderstood the difference in the Horizon betweene the true and the magneticall Meridian By the Set is meant the setting or placing of the wyers in the bottome of the Flie which sometimes you shal finde standing right vnder the Flower de luce representing the North point sometimes ½ ⅓ c. toward the East of the Flower de luce The Compasse being artificially made and fitted as he ought to be with al his iust regards we must cōceaue euery line drawen from the Center vnto each diuision to represent alwayes the semidiameter of an Azimuth bearing the same name with the diuision of the instrument The line of North South is euery where the intersection of the Meridian with the Horizon and the line that crosseth him at right angles is euery where the intersectiō of the East West Azimuth with the Horizon The like is to be vnderstood of euery one of the other according to their natures so that euery point of the Cōpas when the line thereof is by imagination produced in the Horizon vnto the Heauens is vnderstood to be the base of a Quadrant of some one Azimuth or other and the line falling from the Zenith to the Center of the Compas is as the Perpendicular cōmon to them all Wherefore which way soeuer in any situation a ship doth saile vpon any point of the Compas it must needes be that shee sayleth within the plaine of one Azimuth or other in as much as euery point is the Base of an Azimuth and so performeth alwayes her course vpon the Conuexe of the Sea in a portion or portions of one great Circle or other because all Azimuthes are great Circles Albeit therfore a voyage were to be made from any place in any Latitude more or lesse it skilleth not vnto any other of the same Latitude and that according to the common trade which should not be if great Circle-sayling were knowen brought to perfectiō keeping as neere as may be vnder one Parallele from the beginning to the ende of the voyage yet because in all this Ships motion the Compas is considered as equidistant alwayes vnto the Horizon it must needes followe that all the points of the Compasse his Variation remembred continue their mutuall respect to those of euery Horizon the line of South and North being still the Intersection of the Meridian with the Horizon the line of East and West being still the Intersection of the East and West Azimuth with the Horizon crossing one an other alwayes at right angles so that the situation of the shippe continually altering doeth neuer alter the properties of the Compas whose nature is to deriue those his diuisions vnto euery newe Horizon that hee approcheth vnto all the lines of his points euer remaining Semidiameters of Azimuthes and Bases of their quadrants the line falling from the Zenith through his Center being still the perpendicular common to them all Whereby it is manifest that in as much as the direction of the sayling Compasse is alwayes some one Semidiameter of an Azimuth and the shippe being the body mooued euer stemmeth in the plaine of the selfe same Azimuth also the winde being the efficient that moueth of his mutable propertie driueth foreright diametrally vpon the plaine of the Horizon which cannot be but according to the intersection of the foresaid Azimuth it is therefore impossible if the shippe be moued that is transferred or changed from place to place that the line or tracing of her course comprehended betweene those places should be any other but onely such as is composed of great Circular portions of which the length of the shippe it selfe is alwayes a segment And so describeth she by that meanes in her course before mentioned not a Parallele properly so called as common opinion doth wrongfully imagine consisting of one continual lesser Circular line or otherwise a Spirall line truely so named consisting of a continuall vniforme winding answerable to the nature of the said line but a course quibusdam diuerticulis as learned Nonius termeth it with certaine turnings in and out consisting of small segments of great Circles keeping alwayes as neere the precise parallele or Spirall line as arte can ayde them Wherefore it is confessed that those seuerall courses haue some shew or resemblance of the two sorts of lines aforesaide but by no meanes are they the very lines themselues in deede Who was the first inuenter of this Instrument miraculous and endued as it were with life can hardly be found The lame tale of one Flauius at Amelphis in the kingdome of Naples for to haue deuised it is of very slender probabilitie Pandulphus Collenutius writing the Neapolitane historie telleth vs that they of Amelphis say it is a common opinion there that it was first found out among them But Polidore Virgil who searched most diligently for the Inuentors of things could neuer heare of this opinion yet himselfe being an Italian and as he confesseth in the later ende of his third booke de inuentoribus rerum could neuer vnderstand any thing concerning the first inuention of this instrument Most men suppose the finding thereof to bee very newe and hardly to be proued that it hath beene in any vse in these partes of the Worlde full 200. yeeres agone But whether this propertie of the Loadstone was first knowen in the West or East partes of the world it is very doubtfull The East Indian histories are pestered with such monstrous reports and Legendarie tales that as yet they are but of very small credite Their fabulous genealogies and Frierly discourses doe breede a lingering expectation of some halting Poste that making not so much haste as good speede may with more sinceritie enforme vs of the state of those Countreis and matters vnto them belonging Some fewe yeeres since it so fell out that I had seuerall conference with two East Indians which were brought into England by master Candish and had learned our language The one of them was of Mamillia in the Isle of Luzon the other
are commonly so vnhandsomely made and ill fauouredly hanged vpon their pinnes that you should offer a Tincker discredit to compare his worke with this Adde hereunto the riuetting of the Circles with yron and hanging the bigger of them vpon yron nayles which although they be but little yet you must esteeme a litle in this case to bee a great deale too much And if they had any care of that they haue in hand they would not commit such a needelesse grosse absurditie onely as it were in despite of Arte to make expense of wit without gaine or profite The piece of Lead that is fastened to the bottome ought to be round and of equall thicknesse the pinne passing through the Center thereof If you haue it otherwise then marke the Boxe and the bottome when it hangeth aright and whensoeuer hauing taken off the bottome you will set it on againe see that you make your markes in the Boxe and bottome agree or else it can neuer with any certeintie hang as it should Although it be exceeding lothsome vnto me to deale in these mechanicall base practises yet the necessitie is such that one must needes deale therein For of all the Instruments that the Nauigator vseth this is farre the most excellent and yet of all others this is most negligently and vnartificially made Their Staues and Sea Cardes made in England are neate and fine Their Astrolabes are tolerable but these are euen such as I haue shewed vnto you which I could not so well haue shewed but by this anatomizing of them that the blame may bee apparant either in those that make them or in such as buy them that will not goe to the price of better wherein folly would shewe it selfe very eminent if when a shippe with her lading may bee woorth many thousands of poundes besides the inestimable value of the mens liues that are in her halfe a pound should be thought much to be bestowed on a perfect Compasse vpon the goodnesse whereof many times both shippe and goods and liues of men doe take their triall yea all these doe they ieopard as it were vpon a wager that their Compasse is true and perfect To conclude I would wish in any wise that Artificers of these Instruments shoulde make euen great conscience of that they haue in hand and not sleightly to passe them ouer after the order of dozen ware Also that such as exactly make them should be rewarded and esteemed accordingly And finally that they which are to vse them doe well examine their goodnesse before they buy them Moreouer it many times falleth out that the hollowe side of the Capitall is made too narrowe in the bottome and then will the Flie neuer play well except the pinne be exceeding small sharpe which assoone as by vse it is a little dulled the Flie will neuer shewe his pointes truely though hee were touched with the best stone in the world And very oftentimes the ouersight herein is imputed wrongfully to the weaknesse of the Touch. And therefore take care that the greater Boxe being square be not set together with yron nayles But if it be round then see that it be handsomely turned And in any wise that the lesser Boxe wherein the Flie standeth be well exactly turned of seasoned wood and hauing the inside coloured with some white glistering colour and not according to the common custome rubbed about with a piece of Chalke or a little white lime Furthermore because it is very necessarie that whosoeuer sayleth by any Carde ought diligently to foresee that the Set of his Compasse be answerable to his Card of the like Set I meane vnto that his Card was made by And for that the wyers being once glewed on may not well be altered or remoued And the double Flie by reasō of his vnwildie corpulēcie is nothing nimble I haue framed one after this sort a briefe description whereof I thought not impertinent here to insert The endes of the wyers must bee welded together The wyers themselues are halfe round with the otherside flatte to be placed vpon the bottome of the Flie. The Capitell hath two thinne narrowe Stayes of Latten reaching to the wyers on each side and fast soldered vnto them The toppe of the Capitell must bee skrewed on the outside and a little square piece of Latten with a small hollowe bent fitted for to skrewe vpon him vnto this ende that the Capitell being put through the bottome of the Flie in the Centre and the skrewe on the vpper side being turned on the top of the Capitell the Flie and wyers both may by this meanes bee closely combined together without any paste or glewe and bee left bare throughout to the most aduantage at any time for receauing the touche of the Stone and more easily be kept from rust being the greatest enemie that the touche of the Stone can haue vnto which all your pasted or glewed wyers are necessarily subiect insomuch as you shall very seldome and as I thinke neuer in the whole many of your vsuall Flies see any one that is not infected herewith being farre more noisome then Garlike or Oile and all the rest of those fondly surmised conceites If the skrewe come not close ynough vpon the Flie a little piece of pastboorde put on before the skrew will be a remedie sufficient therein When the wyers are thus fastened vnto the Flie you may at al times remoue them to any point or part of a point at your pleasure without anoyance vnto any thing In such as I haue caused to be made for this purpose I haue vsed a narrowe forme of a loope the distance betweene the wyers in the middle being little more then the fifth part of their length and haue abated also the mettall of the wyars about the middle of them and allowed somewhat the more towards their ends The Compasse of Variation THe Compasse of Variation is made in all respects like vnto the ordinary sayling Compasse is the very same in deede excepting these two Additions The one is that on the inside of the lesser Boxe round about iust with the height of the Flie either vpon the Boxe it selfe or else vpon Paper or Pastboorde fastened to the side thereof there be a Circle diuided into 360. partes And at euery 90. let a line be produced both vpward to the top and by the space of halfe an ynche downeward At any one of which lines make a Flower de luce representing the North and there begin your numbers on both sides thereof from 1 vnto 90. doe the like also from the opposite part betokening the South The other is that a thwart the vpper face of the Glasse there be placed a Ruler of Latten in length answerable to the Diameter of the Boxe bearing in breadth the third part of an ynche or halfe an ynche if you thinke good for a very great Compasse In the middle of which Ruler there must a line bee drawen according to the length
of the Ruler And toward eache end of equall distance therefrom fitte two Sights of three ynches or longer as your Compasis and about a quarter of an ynche broade at the toppe waxing broader toward the foote where they are to be ioynted in such sort that they may for handsomenesse sake be folded the one close vpon the other and stand erected at right angles In the one of these along the middle thereof cut out the mettall beginning a little beneath the top downe to the foote of conuenient breadth that a Lute string hauing a small pearle or bugle on it to slide vp and downe may be fastened precisely in the middle throughout from the toppe to the foote The other Sight being made after the same proportion and forme that the former was hath onely a fine small slit pearced from within very little off the toppe downe to the foote and must in his thickenesse be abated that he weigh no more then the other The Ruler thus furnished with his Sights in the space betweene the sights and the brimme of the Boxe ought to haue two loopes cut out in decent maner to looke downe through them vpon the Flie. And this Ruler must be diuided into many equall small partes as 20 to an ynche or such like the numbers beginning from the Lute string sight vnto the other and from the foote of that other to the toppe When the Ruler is finished as before I haue specified it must a little be let into the brimme of the Boxe that it may stand fast hauing the middle of it right ouer the line of North and South in the Boxe and the Sight with the Lute string ouer the South But let it in such sort be fastened that you may conueniently either take it off or set it on as occasion shall serue So that the Ruler being taken off it is a Sayling Compasse being set on it serueth for the Variation in maner following The Flie of the Compas hauing at opposite partes directly ouer the points of the wyers some markes on the vpper side easie to be discerned if it be a Meridionall Flie it needeth not in as much as the Flower de luce and the South point serue the purpose turne the Boxe toward the East in the foorenoone with the Ruler on it till the Lute string doe cast his shadowe right vpon the middle line of the Ruler or on the slit of the other Sight Then marke immediatly where the shadowe of the pearle doth light vpon what diuision if the lines be diuided otherwise marke it with a penne And also what part the Southend of the wyers or which is all one the Northend doth point vnto in the side of the Boxe In the afternoone doe the like toward the West with the pearle still vnremooued turning the Boxe till the shadowe of the pearle falleth full vpon the place that it did in the forenoone And note then also what part the endes of the wyers doe point vnto Then if the number of partes obserued in the forenoone be alone with those in the afternoone there is no Variation at all for the ends of the wyers doe shewe the true Meridian But if the one exceede the other subtrahe the lesser from the greater And halfe the remainder is the Variation of the Compasse toward that side which had the greater number in his obseruation This Compasse serueth farre better to set the land withall and to describe any Harbour Coaste Hauen Towne or Countrey then any before in common vse by looking through the slitte and bringing the thing that you would note and the Lute string both in one withall marking what partes the wyers doe shewe at that instant Likewise for taking of distances All this may also bee performed with a Circle of Latten about one quarter of an ynche broade hauing a stay going athwart perced through with loope holes that it be no hindrance to viewe the Flie and a Ruler mouing vpon it in forme like to the former Which Circle must be diuided as that within the Boxe was frō the Flower de luce which is to be placed a quarter of a Circle distant frō the line passing along the middle of the stay haue his numbers reckoned towards the endes of the same line And so must the other halfe of the Circle be diuided from the South point Being thus diuided it must be placed euen fast and very fitte close aboue the Glasse And when you will vse it turne the Boxe about till the flower de luce of the Circle stand right ouer the Northerly endes of the wyers And the Boxe so standing set the Ruler according to the forenoone and afternoones obseruation doing all things els as before And you shall finde the selfe same effect I haue tryed at land the Crosse-needle in steade of the Flie and do like it exceeding well Whether is the better at Sea I doe referre it vnto their iudgements that shall make due triall of both The Crosse-needle I call two needles the one of Steele and the other of Latten ioyned together in the Capitell where they crosse each other at right angles and so made that they be of one length very straight and equally standing vpon the pinne no end ouerweyghing the other This Needle well made and fitted as it ought to bee will besides his proper vse supply the vse also of a Perpendicle a matter of great importance to shewe the vpright standing of your Instrument which the single Needle cannot doe neither yet the Flie any whit comparable vnto this But you are diligently to note that in continuance of time as the force of the Touch of the Stone doeth decay so will the North ende of either Needle or Flie rise somewhat higher and the South end sincke lower For this is one of the wonderful properties that the touch of the Magnete hath that a needle as yet not touched standing equally vpō his pinne being once touched with whether ende of the Stone you list the one end thereof shalbe reared higher and the other fall lower The difference whereof as the goodnes of the Stone is greater will accordingly the more appeare And in processe of time as his force stil decaieth so returneth hee more and more to his euen standing againe By reason of which propertie the Artificer is constrained that he may make the Needle lie euen to abate somewhat of the falling end that the other by vertue of the touch raised vp may through this abatement be brought downe to an equalitie of situation with his fellowe When therefore you perceaue the rising of the North end as aforesaid assure your selfe the Flie or Needle is weakened in strength and hath neede to be refreshed with the Stone Otherwise if it were at the first well touched be not too busie with it but let it alone except you bee well assured of the goodnesse of the Stone and of the right maner of touching If the Northend riseth not any thing at all and
of the Horizontall must be filled vp with the Centre-pinne thereof in such sort that being from vnderneath fastened thereinto the one halfe and more of the said Pinne somewhat beyond the Diameter of his thicknes shalbe cut away and be made euen with the vpper side of the Horizontall But the other part remaining shall stand directly vpright of a conuenient length aboue the Horizontall And this I terme the Axis of the Verticall because by meanes of it the Verticall is turned round about vpon the Horizontall and made to take any maner of position The Verticall hath in it a Quadrant as bigge as it may receaue to be drawen not after the common fashion but according to the description inuented by that famous Mathematician Petrus Nonius in his Treatise of Instruments and Rules for Nauigation and of the Twilight which Quadrant in respect of the kinde of working thereby I call the Proportionall Quadrant And on that side it hath nothing else sauing the Alhidada or Sight Ruler as the maner is fastened in the Center and carying in his margen aboue the Fiduciall or Leuell-line all the seuerall numbers of the inner Quadrants vnderneath for more readinesse and certaintie sake For the speedier diuiding of the inner Quadrants doe thus Part the Fiduciall line of the Sight Ruler into halfes from the innermost circumference of the Limbe vnto the Center The medietie next vnto the Limbe diuide into 45. equall partes setting downe their seuerall denominations by fiues or tennes vpon the Ruler rightouer the diuisions their numbers decreasing from the Limbe towards the medietie after this sort The diuision next vnto the Limbe is accounted for to be 89. the next 88. then 87. 86. c. vntil you come vnto 46. next vnto the medietie it selfe According vnto these diuisions precisely answering vnto them drawe so many inner Quadrants vpon the Center of the great Quadrant of 90. Then must you with a payre of diuiding Compasses very exactly take the quantitie of a degree in the Quadrant of 90. and that will perfectly diuide euery one of the inner Quadrants into their assigned numbers Onely you are carefully to foresee that when the Verticall on the backe part thereof through the hole of his Border is firmely fixed vpon the Axis of the Center-pinne the neathermost edge on the forepart of it being equally distant from the lower side or Base of the proportionall Quadrant doe in any case precisely light vpon the Center of the Horizontall to the ende that it may alwayes serue it in steade of a moueable Diameter The backe of the Verticall hath these three necessarie Implements The first is a Compasse with his line of North and South parallele to the Verticall And the same must be handsomely and fitly let in to the border of the Verticall beneath that the Axis of the Center pinne passing through both the handle of the Compasse and the said Border may claspe it exactly close vnto both the backe of the Verticall and the plaine of the Horizontall in such sort that as the Verticall is moued round about so ioyntly together with it and in it shall the Compasse likewise The second is the Directory so named because it guideth the eye-beame directly foorth vnto the Horizon And this consisteth of two partes The Ruler and his Sights Whereof the Ruler being of a reasonable length streight and euen shall be drawen to and fro athwart the backe of the Verticall in two loopes standing parallele to the Horizontall or which is all one to the Border of the Verticall The two Sights which ought to be 2. or 3. inches long are moueable likewise but vpon the Ruler the one beyond the Verticall the other behether it towards your eye The third is the Perpendicle or threed with a little plummet hanging thereat requisite for the due placing of the Horizontall which turne the Cross-needle also will serue Last of all when you are to vse the Verticall alone by it selfe as hereafter shall be shewed you there is a handle belonging thereunto hauing the lower ende of what forme you will the best is which may best fill the hand but the vpper end must be of the same fashion and bignesse that the Axis of the Centre-pinne is of for it hath as you shall perceaue the same vse and must be fastened likewise in the same place The Mechanicall Description of those Partes The Horizontall The Compasse The Backe of the Verticall with his Border Inlets Loopes and Perpendicle The Centre-pinne The Verticall and his Sight-Ruler The Directory The handle of the Verticall The exact finding of Altitudes or Heights FOr as much as the vsuall Quadrant of 90. degrees onely doeth very seldome yeeld the precise eleuation sought for in a knowen and certaine denomination because most commonly the Sight Ruler or Alhidada as they call it cutteth not exactly at a full degree but vpon the space betweene the beginning and ending of a degree which is infinitely diuisible the proportionall Quadrant of Nonius by drawing and diuiding many inner Quadrants as before you haue seene shewes that easily within a narrowe circuite which otherwise a very large yea a huge Instrument with no small incumbrance would hardly doe in a mightie circumference For the partes being so many in a continuall traine following one an other and the Ruler euery where in a maner crossing them it must needes cut some one of the inner Quadrants vpon a full degree And so by this meanes that part of the vttermost or great Quadrant which before was but confusedly coniectured without any determinate denomination is now distinctly made knowen vnder a certaine name by the ready helpe of the Golden Rule after this maner When the Ruler sheweth some portion of a degree in the vttermost Quadrant whose certaine value in minutes seconds c. you would gladly learne obserue at the same instant what whole degree in one of the inner Quadrants it precisely cutteth And market therewithall in the side of the Ruler the entire summe of all the parts whereinto that Quadrant is diuided So haue you of foure proportionall numbers three giuen namely the whole inner Quadrant his part cut and the whole vttermost Quadrant of 90. Wherefore to finde out the fourth multiplie 90. into the partes of the inner Quadrant that the Ruler cut and the Product diuide by the whole inner Quadrant the Quotient shall tell you the degrees of the vttermost Quadrant together with the portion sought for in a fraction distinctly knowen which to reduce vnto the vsuall denomination of Minutes Seconds c. doe thus Multiplie the Numerator of your Fraction by 60 and diuide the product by the Denominator the Quotient shewes your Minutes And if any remainder be againe multiplie that by 60. and diuide in like sort as before this second Operation brings foorth Seconds And in the same maner still working as often as any thing is left of the former Operation you may proceede on to Thirds Fourthes Fifthes
c. till you haue obteyned a most sufficient precisenesse The Obseruing of the Variation at Land by the Sunne SEt the Instrument vpon a Staffe prepared for this purpose his Horizontall being parallele to the Horizon of the World And placing the Verticall vpon the line of North and South in the Horizontall turne the Horizontall about till the Needle stand equidistant to the Verticall Then fasten the Horizontall to the staffe with the skrewe pinne of his Socket which in that sort remaining steaddy and immoueable turne the Verticall in the Forenoone towards the East mouing the Sight Ruler vp and downe till the Sunne beame doth pearce both Sights and immediatly note what partes the edge of the Verticall doth cut in the Horizontall Also what part the Sight-Ruler falleth on in the Verticall where if it light not on a iust part in the vtter Quadrant marke where it doth vpon one in any of the inner Quadrants Againe in the Afternoone the Horizontall continuing still in his former place and the Ruler likewise abiding vpon the foresaid part vnchangeable turne the Verticall towards the West till the Sunne entreth in at both the sights And note therewithall what part the edge of the Verticall cutteth in the Horizontall If then the partes cut by the edge of the Verticall in the Forenoone and those other in the Afternoone bee equally distant from the South point of the Horizontall then is there no Variation at all For the line of North and South in the Horizontall is one and the selfe same with the true Meridian But if the partes of the Forenoones obseruation be fewer then those of the Afternoone subtrahe the smaller number from the greater and halfe the remainder discouereth the Variation from the South Westwards to bee so many degrees and the Northerly end of the Needle to decline so many parts from the true North towards the East Wherefore the line of North and South in the Horizontall doeth not possesse the true Meridian but swarueth therefrom as the partes obserued doe shewe Lastly if the partes of the Forenoones obseruation be moe then those of the Afternoone subtrahe as before the smaller number from the greater and halfe the remainder sheweth the Variation of the South end of the Needle to be so many degrees Eastward and the Northerly end thereof to vary so many partes Westward Nowe for the more certeinetie in your working you must euer be mindfull to make 3. or 4. seuerall obseruations in the Forenoone that although a Cloude should hinder you of your first in the Afternoone yet some one at the least of the other may be clearely obserued where otherwise if you misse of one all your labour for that whole day is lost The obseruing of the Variation at Land by the Starres THe Variation of the Compasse and so likewise the Latitude may bee taken as well by the Starres in the night as by the Sunne in the day And sithe the Almightie hath ordeyned but one Sunne and a great multitude of Starres Nauigators should offer themselues much wrong if they would not make their benefite of these as they do of that And so much the rather because the Sunne is South but once in foure and twentie houres The Starres come to the Meridian continually one after another all the night long The ordinarie instrument for the Variation is not of any vse at all in respect of the Starres no not though he haue his Astrolabe to helpe him whereas this instrument by it selfe without the ayde of any other performeth all things exquisitely by the Starres And by the Sunne so exactly with all aduantage that when many Instruments can doe nothing without a cleare Sunneshine this in a mystie or foggie weather through a Cloude if that you may but onely discerne the body of the Sunne craueth no more to accomplish your desire The maner of obseruing a Starre is this First prepare a little Notche or slit of equall deapth in the two sights of the sight-Ruler parallele to the leauell line thereof And the Instrument being placed as before is specified turne the Verticall towards the Starre being on the Eastside of the Meridian mouing the sight-Ruler vp or downe till you may perceaue the Starre euen with those two Notches Then note the partes that the sight Ruler doth cut in the Quadrant And those also that the edge of the Quadrant or Verticall cutteth in the Horizontall Afterward doe the like againe when the same starre is on the West side of the Meridian And for the rest following the same maner of Operation that aboue I deliuered you shall here obteine the selfe same trueth of Variation by any starre that there you found onely by the Sunne Touching the Latitude the like kinde of working is to be vsed for the taking thereof by a starre as is by the sunne I meane the obseruing of his Meridian height and subtrahing or adding as the nature thereof requireth And for this cause is the Verticall so placed that about an ynch of it more or lesse according to the proportion of the Instrument at that corner where the Ruler is fastened to the Center may alwayes in the turning about reache ouer the Horizontall that you may conueniently apply your eye by the sights to discerne any starre or espie the top of any body erected whose height you would measure which otherwise you could not doe if the Verticall were but euen with the Horizontall As for the other end of the Base of the Verticall it is no matter howe farre it be extended but onely according as the quantitie and comelines of the Instrument shall require so that the Border wherewith the Base of the Verticall is lengthened doe reache precisely streight and euen vnto the edge of the Horizontall for the cutting of the partes therof Moreouer if the halfe Circle of the Horizontall which is parted into degrees were diuided also into a payre of Proportionall Quadrants then both for the former vses and infinite others woulde this Instrument prooue most exact and persite But those that are willing to bestowe so much cost I wish they should doe it in mettall and not in wood If in wood then let the same especially be chosen whereof Cypers chests are made For that I take to be best as being most free from warping and receauing any worke very easily and fairely The imperfection of bricklenesse a little the more care must amend and strengthen And thus much for the vse of the Pantometer complete The maner of obseruing the Variation at Sea WHen the Verticall of the Pantometer together with his Compasse is fitted to the handle holde it directly toward the Sunne in the Forenoone in such sort that the Perpendicle keeping his due place the Sunne may pearce both the sights And noting the height of the sunne marke also at that instant what Point or Degree the Needle doth shew Againe when the Sunne commeth to the same height in the Afternoone obserue likewise what Point