M. Blundevile his exercises containing sixe treatises, the titles wherof are set down in the next printed page: which treatises are verie necessarie to be read and learned of all yoong gentlemen that haue not bene exercised in such disciplines, and yet are desirous to haue knowledge as well in cosmographie, astronomie, and geographie, as also in the arte of navigation ... To the furtherance of which arte of navigation, the said M. Blundevile speciallie wrote the said treatises and of meere good will doth dedicate the same to all the young gentlemen of this realme.

How to know the diuersities of the ascentions and descen∣tions, as well in the right as oblique Spheare. Chap. 33.

THat is to be knowne most exactly by the Tables of ascentions calculated of pur∣pose by Iohannes de Monte Regio, and by Reinholdus called in Latine Tabulae directionum, and you may knowe it also without hauing respect to euery minute by marking and obseruing the same in a materiall Spheare or Globe, that hath a standing foote with a firme Horizon, for if you will know the diuer∣sities of ascentions in a right Spheare, then you must lay the Spheare or Globe so as the Horizon may passe through both the Poles, and in turning about with your hand the Equinoctiall, to∣gether with the Ecliptique from East to West, marke with what degrée of the Equinoctiall any signe beginneth to ascend, & marke that degrée of the Equinoctiall with a little peece of waxe, then turne the Globe or Spheare towardes the West, vntill the last de∣grée of the sayd signe doe appeare iust with the vpper edge of the Horizon, and then marke what degrée of the Equinoctiall is aun∣swerable to the said last degrée of the foresaid signe, and there set another péece of waxe, then count the degrées of the Equinoctiall contayned betwixt those two markes, and if it be more then 30. that signe is said to ascend rightly, if it be lesse then 30. then that signe ascendeth obliquely, if it be iust 30. then it hath a meane as∣cention, & by allowing 15. degrées of the Equinoctial to an houre, and 4′· to a degrée, you shall know in what time that signe riseth. As for example if you would know what ascention the whol signe Taurus hath in a right Spheare, and also in what time it riseth, doe thus, First lay both the Poles of the Spheare iust vpon the Horizon, so as the same Horizon may passe through both y^e poles, then bring the first point of Taurus to the East part of the Hori∣zon, so as it may touch the vpper brimme or edge of the Horizon, and staying it there with your hande, looke what degrée of the E∣quinoctiall doth also touch the Horizon at that instant, which you shall finde to be 27. degrées 54′· and marke that degrée of the Equinoctiall with a little péece of waxe, or some other thing

that may be easily put out or taken away, that done, put forwarde the foresaid signe Taurus still towardes the West, vntill the last degrée of the saide signe be ascended vp euen to the vpper edge of the Horizon, and there staying it with your hande, looke againe what degrée of the Equinoctiall doth rise withall, which you shall finde to be 57. degrées 48′· and there set another marke vppon the Equinoctiall, then by telling the degrées conteyned in the Equinoctiall betwixt the two markes, you shall finde the number of degrées to be 29. degrées 54′· and by allowing 15. degrées to one houre, and 4′· to a degrée, you shall finde that the whole signe Taurus spendeth in his rising one houre, 59′· 36″· But now sith the Meridian in any place (as hath béene said before) doth alwaies shew the right ascention of any starre, signe, arke, or point, be∣cause that cutteth both the Equinoctiall and the Horizon with right Angles: you may therefore find the right ascention of the sayd signe, or of any other signe or starre without remoouing the Spheare from your owne eleuation or Latitude in this manner following, bring the first degrée of Taurus close to the mooueable Meridian, and there staying it marke what degrée of the Equi∣noctiall the Meridian cutteth at that present, which you shall find to be 27. degrées 54′· which is the right ascention of the first point of Taurus, then hauing brought the last point of Taurus to the foresaide Meridian, marke what degrée of the Equinoctiall the sayd Meridian cutteth at that present, and you shall finde it to bée the 57. degrées 48′· now by counting vpon the Equinoctiall, the degrées conteyned betwixt those two markes, you shall finde the number to be 29. degrées 54′· and you may finde the selfe same number by subtracting the right ascention of the first point of Taurus, out of the right ascention of the last point of Taurus, & thereby you shal know the time of his rising to be the same that you found in the right Spheare. Now if you would know the as∣cention of any signe in an oblique Spheare, then hauing placed your Spheare according to your Latitude, which for example sake suppose to be 52. degrées, and that in such Latitude you would know what ascention the whole signe Taurus hath, and in what time he riseth, you must first bring the first degrée of Tau∣rus to the East part of the Horizon, so as it may méete euen with the vpper edge of the Horizon, and there staying it, marke what

degrée of the Equinoctiall riseth therewith, which you shall finde to be 12. degrées 48′· and hauing marked that degrée, put forward the foresaid signe Taurus towards the West vntill the last degrée thereof be ascended vp to the vpper edge of the Horizon, and then make another marke vpon the point of the Equinoctiall, which riseth at that instant with the last degrée of Taurus, which you shal finde to be 29. degrées 42′· and by counting the degrées contained in the Equinoctiall betwixt the two markes, or by taking the lesser ascention out of the greater, you shall finde the number of degrées to be 16. and 54′· whereby you may conclude that the ascention of Taurus in that Latitude is oblique, and that he spendeth in his rising one whole houre 7′· 36″· And looke what order is héere taught to finde out the ascention of any signe, the same order is to be obserued for the finding out of the descention of any signe, sauing that you must séeke for the descention of any signe in the West part of the Horizon of the Spheare or Globe, and not in the East part. As for example, if you would knowe what descen∣tion Taurus hath, and in what time he descendeth in the foresaide Latitude: here hauing brought the first degrée of Taurus to the West part of the Horizon, so as it may touch the vpper edge ther∣of, and hauing also marked what point or degrée of the Equinoc∣tiall toucheth the same Horizon at that instant, which you shal find to be 42. degrées 30′· cease not to turne the Spheare or Globe, vntill all the whole signe of Taurus be descended vnder the Hori∣zon, and that the last degrée thereof doe méete iust with the vpper edge of the Horizon, and there stay it vntill you haue againe mar∣ked that point of the Equinoctiall which toucheth the Horizon at that instant, which you shall finde to be 84. degrées 54′· and by counting the degrées contained betwixt the two markes on the E∣quinoctiall, you shall find the number of degrées to be 42. degrées 24′· so as you may conclude that the descention of Taurus in that Latitude is right, and that he spendeth in his going downe two houres 48′·

How shall I knowe the right or oblique ascention of any of the fixed starres, and also at what houre of the day or night they rise & set, and how long they abide aboue the Horizon: finally when they are at the highest, and when they are at the lowest, called the depression or lowest Meridian Altitude of

the starres?

All these things are most truely knowne by Tables calcula∣ted of purpose, and also they are to be knowne by helpe of the cele∣stiall Globe in such manner as shall be declared hereafter when we come to treate of the said Globe.