The description and use of the globes, and the orrery; to which is prefixed a brief account of the solar system
John Harris
Paperback
(RareBooksClub.com, June 28, 2012)
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1732 edition. Excerpt: ...having a Nut and Screw ofdtituA: at one End, to be fastened to the Meridian of ekher Globe, as occasion requires. The Edge of this Quadrant, which has the Graduations upon it, called the fiducial Edge, is that which is always meant whenever we make mention of the Quadrant of Altitude. 4. The Horary or Hour Circle is divided Hour c»into twice twelve Hours; the two XI1V coinciding with the Meridian: the uppermost XII is that at Noon, and the lowermost towards the Horizon is XII at Night. The Hours on the East Side of the Meridian are the Morning Hours, and those on the West Side the Hours after Noon. The Axis of the Globe carries round the Hand or Index which points the Hour, and it is the Center of the Hour Circle. The The Things above described are common to both Globes; but there are some others which are peculiar, or proper to one sort of Globe. The two Colures, and the Circles of Latitude, from the Ecliptick, belong only to the Celestial Globe; also the Ecliptick it self does properly belong only to this Globe, tho' it is always drawn on the Terrestrial, for the fake of those that might not have the other Globe by them. The Equinoctial on the Celestial Globe is always numbered into 3 60 Degrees, beginning at the Equinoctial Point r; but on the Terrestrial, it is arbitrary where these Numbers commence, according to the Meridian of what Place you intend for your first; and the Degrees may be counted either quite round to 3 60, or both Ways, till they meet in the opposite Part of the Meridian at 180, SECT SECT. III. The USE of the Glob Es. Problem I. To find the Latitude and Longitude of any given 'Place upon the Globe-, and on the contrary, the Latitude and Longitude being given, to find the Tlace. i.'T'URN the Globe round its Axis, g till...