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 find out the degree of Medium coeli at any houre, of the day (that is to say) the degree of the Zodiaque that is in the Meridian at any houre that you seeke, and also the de∣gree called Imum caeli. The 29. Proposition.

FIrst séeke out the place of the sunne for that day in the Zodiaque of the Rete, and hauing laid the labell to the houre supposed vpon the limb of the Mater, bring the place of the sunne to the Fiduciall line of the label, and there staying the Rete, looke what degrée of the said Zodiaque cutteth the noone line or Meridian at noonetide, which you shall easily find by laying the labell to the houre of 12. at noone, for the Fiduciall line of the label crossing the Zodiaque, will shew the degrée of mid heauen at that houre. As for example, the 26. of Iune 1592. I would know the degrée of Medium coeli, at eight of the clocke in the morning, the sunne being that day in the 14. of Cancer. Here by laying the labell to the said houre in the limbe of the Mater, I bring the place of the sunne to the Fiducial line of the labell, and there hauing stayde the Rete, I bring the la∣bell to the twelfth houre at noone, and I find that the labell cutteth the Zodiaque of the Rete in the 18. of Taurus, which at that houre is the degrée of Medium coeli, whose point opposite is the 18. degrée of Scorpio, and that is at that houre Imum coeli▪ which the labell being laid to the 12. houre of midnight will shew.