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This, however, MBT Shoes is far from being the case; the enlightened hemisphere is in all the positions of the moon that turned towards the sun, and therefore, there are certain of these positions in which it is turned altogether from the earth; certain others in which it is partially turned from it; and only one position in which it is altogether turned towards the earth.' Thus then, there are certain positions in which we see none of the moons enlightened disc, i.e., we do not see the moon. m| all, certain others in which we see only part of it, and only one position in which we see the whole disc.The orbit of the moon is but slightly inclined at an angle of , to the plane of the ecliptic, that is, to the plane in which the earth devolves about the sun. Hence, therefore, there are certain positions of the moon in her orbit in which she lies between us and the sun, and certain others in which we lie between her and the sun. Let a, a„ a„ arepresent different of those positions of the moon in her orbit, and draw planes MBT Shoes UK ab, a, b,, a bf through her centre, perpendicular to the direction of the sun's rajs failing upon her in each of these positions. Then it is manifest that amb, ai v% bi, at nt b, &c„ will be the enlightened hemispheres of the moons surface, and that the opposite hemispheres will be dark; also, that in the position m no part of this enlightened hemisphere can be seen from the earth; that in the position ml only the portion bt Cj can be seen; MBT Sale in the position m only b c«; in the position m only b c, &c. If the moon were near enough to us, we should thus see at different times portions of her surface, which would have the appearance of different sections of a' spherical surface. But by reason of the great distance of the moon, we cannot distinguish that variety of shading by which the portion of the enlightened surface which we see may be ascertained to be that of a solid; and it appears MBT to us to be perfectly flat. The width of this perfectly flat portion which we thus see is in the position m, ; the distance between two lines drawn, one from' e to the boundary b of the enlightened part, and the other to the boundary cr And this distance Cj n is what is called the versed sine of the angle b o, cNow this angle bx o, cl is easily seen to be equal to the angle o,emj that is, it is equal to the angular distance of the moon from the sun; or, as it is termed, the moons elongation.
This, however, MBT Shoes is far from being the case; the enlightened hemisphere is in all the positions of the moon that turned towards the sun, and therefore, there are certain of these positions in which it is turned altogether from the earth; certain others in which it is partially turned from it; and only one position in which it is altogether turned towards the earth.' Thus then, there are certain positions in which we see none of the moons enlightened disc, i.e., we do not see the moon. m| all, certain others in which we see only part of it, and only one position in which we see the whole disc.The orbit of the moon is but slightly inclined at an angle of , to the plane of the ecliptic, that is, to the plane in which the earth devolves about the sun. Hence, therefore, there are certain positions of the moon in her orbit in which she lies between us and the sun, and certain others in which we lie between her and the sun. Let a, a„ a„ arepresent different of those positions of the moon in her orbit, and draw planes MBT Shoes UK ab, a, b,, a bf through her centre, perpendicular to the direction of the sun's rajs failing upon her in each of these positions. Then it is manifest that amb, ai v% bi, at nt b, &c„ will be the enlightened hemispheres of the moons surface, and that the opposite hemispheres will be dark; also, that in the position m no part of this enlightened hemisphere can be seen from the earth; that in the position ml only the portion bt Cj can be seen; MBT Sale in the position m only b c«; in the position m only b c, &c. If the moon were near enough to us, we should thus see at different times portions of her surface, which would have the appearance of different sections of a' spherical surface. But by reason of the great distance of the moon, we cannot distinguish that variety of shading by which the portion of the enlightened surface which we see may be ascertained to be that of a solid; and it appears MBT to us to be perfectly flat. The width of this perfectly flat portion which we thus see is in the position m, ; the distance between two lines drawn, one from' e to the boundary b of the enlightened part, and the other to the boundary cr And this distance Cj n is what is called the versed sine of the angle b o, cNow this angle bx o, cl is easily seen to be equal to the angle o,emj that is, it is equal to the angular distance of the moon from the sun; or, as it is termed, the moons elongation.