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.

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Title: 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.
Author: Blundeville, Thomas, fl. 1561.
Publication: London :: Printed by Iohn Windet, dwelling at the signe of the crosse Keies, neere Paules wharffe, and are there to be solde,; 1594.
Rights/Permissions: To the extent possible under law, the Text Creation Partnership has waived all copyright and related or neighboring rights to this keyboarded and encoded edition of the work described above, according to the terms of the CC0 1.0 Public Domain Dedication (http://creativecommons.org/publicdomain/zero/1.0/). This waiver does not extend to any page images or other supplementary files associated with this work, which may be protected by copyright or other license restrictions. Please go to http://www.textcreationpartnership.org/ for more information.
Subject terms: Mercator, Gerhard, 1512-1594.; Plancius, Petrus, 1552-1622.; Blagrave, John, d. 1611.; Astronomy -- Early works to 1800.; Arithmetic -- Early works to 1900.; Trigonometry -- Early works to 1800.; Early maps -- Early works to 1800.
Cite this Item: "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." In the digital collection Early English Books Online. https://name.umdl.umich.edu/A16221.0001.001. University of Michigan Library Digital Collections. Accessed May 15, 2024.

Pages

Of the ascentionall difference and vses thereof. Chap. 34.

WHat is the ascentionall difference?

It is a portion of the Equinoctiall, wher∣by is knowne how much the right ascention and oblique ascention of any star, or portion of the Ecliptique line, or any other point in the firmament, doth differ one from another, As for example in that place where the Pole is eleuated 52. degrées, the right ascention of the first point of Taurus is 27. degrées and 54′· and the oblique ascention of the same point is 12. degrées 48′· here by taking the lesser out of the greater, that is 12. degrées 48′· out of 27. degrées and 54′· there will remaine 15. degrées and 6′· which is the ascentionall dif∣ference.

What vses hath the ascentionall difference?

The ascentionall difference being knowne, all the oblique as∣centions and descentions of the starres are easily knowne by the Tables of directions, againe by this difference is knowne the in∣crease and decrease of the artificiall day in euery Latitude, and therefore it is called of some incrementum diêi. Moreouer it sheweth the semi-diurnall Arke of the artificiall day, for in euery oblique Spheare the artificiall day is alwayes either longer or shorter then the Equinoctiall day throughout the yeare, vnlesse the sunne be in either of the Equinoctiall points.

How is the increase or decrease of the day to be knowne by the ascentionall defference?

That shall be declared hereafter in the 50. Chap. of this first booke, whereas wee treat of the artificiall day and night, in the meane time we will speake somewhat of the poeticall rising and setting of the starres.