A Treatise Describing the Construction, and Explaining the Use of New Celestial and Terrestrial Globes; Designed to Illustrate, the Phoenomena of the Earth and Heavens, by George Adams, (Paperback)

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. 1777 Excerpt: ...longest day in that climate; this holds good for every climate;between the polar circles. A climate is a space upon the sursace of the earth, contained between two parallels of latitude, so sar distant from each other, that the longest day in one differs, half an hour from the longest day in the othejr parallel. The The climates are reckoned from the equator to the polar circle, where the longest day is twenty-four hours; from the polar circle towards the pole the climates are said to increase by a whole natural day, till they come to a parallel under which the longest day is fifteen natural days, or half a months from this the climates are reckoned by half months, or whole months, in the length of the artificial day, till they come to the.pole itself, under which the day is six months long. PROBLEM XXXIII. To find all those places within thef polar circles, on which the fun begins to shine, the time he shines constantly, when he begins to dis appear, thelengthof.hisabsence, as well.as the first and last day of Jiis.appearance to those inhabitants; the day of the month, or latitude of the "place, being given, 251. Bring the given day of-the month on the backside of the strong brass, meridian, to to the plane of the broad paper circle, the surt is just then beginning to shine on all those' places which are in that parallel, just touched by the edge of the broad paper circle; and will for several days seem to skim all around, and but a little above the horizon, just as it appears to us at its setting; but with this observable difference, that whereas our setting fan appears in one part of the horizon only, by them it is seen in every part thereof, from west to south, thence east to north, and so to the west again. Or if the latitude was given, elevate the...