Page:Micrographia - or some physiological descriptions of minute bodies made by magnifying glasses with observations and inquiries thereupon.djvu/150

Rh appears by the help of the Microscope, to be very many degrees smaller then the most acute eye is able to perceive without it. And though one of these six-branched Stars appear'd here below much of the shape described in the Third Figure of the Eighth Scheme; yet I am very apt to think, that could we have a sight of one of them through a Microscope as they are generated in the Clouds before their Figures are vitiated by external accidents, they would exhibit abundance of curiosity and neatness there also, though never so much magnify'd: For since I have observ'd the Figures of Salts and Minerals to be some of them so exceeding small, that I have scarcely been able to perceive them with the Microscope, and yet have they been regular, and since (as far as I have yet examin'd it) there seems to be but one and the same cause that produces both these effects, I think it not irrational to suppose that these pretty figur'd Stars of Snow, when at first generated might be also very regular and exact.

Putting fair Water into a large capacious Vessel of Glass, and exposing it to the cold, I observ'd after a little time, several broad, flat, and thin laminæ, or plates of Ice, crossing the bulk of the water and one another very irregularly, onely most of them seem'd to turn one of their edges towards that side of the Glass which was next it, and seem'd to grow, as 'twere from the inside of the Vessel inwards towards the middle, almost like so many blades of Fern. Having taken several of these plates out of water on the blade of a Knife, I observ'd them figur'd much after the manner of Herring bones, or Fern blades, that is, there was one bigger stem in the middle like the back-bone, and out of it, on either side, were a multitude of small stiriæ, or icicles, like the smaller bones, or the smaller branches in Fern, each of these branches on the one side, were parallel to all the rest on the same side, and all of them seem'd to make an angle with the stem, towards the top, of sixty degrees, and towards the bottom or root of this stem, of 120. See the fourth Figure of the 8. Plate.

I observ'd likewise several very pretty Varieties of Figures in Water, frozen on the top of a broad flat Marble-stone, expos'd to the cold with a little Water on it, some like feathers, some of other shapes, many of them were very much of the shape exprest in the fifth Figure of the 8. Scheme, which is extremely differing from any of the other Figures.

I observ'd likewise, that the shootings of Ice on the top of Water, beginning to freez, were in streight prismatical bodies much like those of roch-peter, that they crost each other usually without any kind of order or rule, that they were always a little higher then the surface of the Water that lay between them; that by degrees those interjacent spaces would be fill'd with Ice also, which usually would be as high as the surface of the rest.

In flakes of Ice that had been frozen on the top of Water to any Rh