Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/108

 that a silver plate boiled, being toucht with the Burnisher, becometh of white obscure; that the moist part of the Earth shews more obscure than the dry; that in the tops of Hills, the woody parts appear more gloomy than the naked and barren; which hapneth because there falleth very much shadow among the Trees, but the open places are illuminated all over by the Sun. And this mixtion of shadow hath such operation, that in tufted velvet, the silk which is cut, is of a far darker colour than that which is not cut, by means of the shadows diffused betwixt thred and thred, and a plain velvet shews much blacker than a Taffata, made of the same silk. So that if there were in the Moon things which should look like great Woods, their aspect might represent unto us the spots which we discover; alike difference would be occasioned, if there were Seas in her: and lastly, nothing hindreth, but that those spots may really be of an obscurer colour than the rest; for thus the snow makes the mountains shew brighter. That which is plainly observed in the Moon is, that its most obscure parts are all plains, with few rises and bancks in them; though some there be; the rest which is of a brighter colour, is all full of rocks, mountains, hillocks of spherical and other figures; and in particular, round about the spots are very great ledges of mountains. That the spots be plain superficies, we have assured proof, in that we see, how that the term which distinguisheth the part illuminated from the obscure, in crossing the spots makes the intersection even, but in the clear parts it shews all craggy and shagged. But I know not as yet whether this evennesse of superficies may be sufficient of it self alone, to make the obscurity appear, and I rather think not. Besides, I account the Moon exceeding different from the Earth; for although I imagine to my self that those are not idle and dead Regions, yet I affirm not, that there are in them motion and life, much less that there are bred plants, animals or other things like to ours; but, if such there be, they should nevertheless be very different, and remote from our imagination. And I am induced so to think, because in the first place, I esteem that the matter of the Lunar Globe consists not of Earth and Water; and this alone sufficeth to take away the generations and alterations resembling ours: but now supposing that there were in the Moon, Water and Earth, yet would they not produce plants and animals like to ours; and this for two principal reasons: The first is, that unto our productions there are required so many variable aspects of the Sun, that without them they would all miscarry: now the habitudes of the Sun towards the Earth are far different from those towards the Moon. We as to the diurnal illumination, have, in the greater part of the Earth, every twenty four hours part day, and part night, which effect in the Moon is monethly: and that annual decli-