Page:Micrographia - or some physiological descriptions of minute bodies made by magnifying glasses with observations and inquiries thereupon.djvu/161

Rh means of which, be the Coal never so long, you may easily blow through it; and this you may presently find, by wetting one end of it with Spittle, and blowing at the other.

But this is not all, for besides those many great and conspicuous irregular spots or pores, if a better Microscope be made use of, there will appear an infinite company of exceedingly small, and very regular pores, so thick and so orderly set, and so close to one another, that they leave very little room or space between them to be fill'd with a solid body, for the apparent interstitia or separating sides of these pores seem so thin in some places, that the texture of a Honey-comb cannot be more porous. Though this be not every where so, the intercurrent partitions in some places being very much thicker in proportion to the holes.

Most of these small pores seem'd to be pretty round, and were rang'd in rows that radiated from the pith to the bark; they all of them seem'd to be continued open pores, running the whole length of the Stick; and that they were all perforated, I try'd by breaking off a very thin sliver of the Coal cross-ways, and then with my Microscope, diligently surveying them against the light, for by that means I was able to see quite through them.

These pores were so exceeding small and thick, that in a line of them, part of an Inch long, I found by numbring them no less then 150. small pores; and therefore in a line of them an Inch long, must be no less then 2700. pores, and in a circular area of an Inch diameter, must be about 5725350. of the like pores; so that a Stick of an Inch Diameter, may containe no less then seven hundred and twenty five thousand, besides 5 Millions of pores, which would, I doubt not, seem even incredible, were not every one left to believe his own eyes. Nay, having since examin'd Cocus, black and green Ebony, Lignum Vitæ, &c. I found, that all these Woods have their pores, abundantly smaller then those of soft light Wood; in so much, that those of Guajacum seem'd not above an eighth part of the bigness of the pores of Beech, but then the Interstitia were thicker; so prodigiously curious are the contrivances, pipes, or sluces by which the Succus nutritius, or Juyce of a Vegetable is convey'd from place to place.

This Observation seems to afford us the true reason of several Phænomena of Coals; as

First, why they look black; and for this we need go no further then the Scheme, for certainly, a body that has so many pores in it as this is discover'd to have, from each of which no light is reflected, must necessarily look black, especially, when the pores are somewhat bigger in proportion to the intervals then they are cut in the Scheme, black being nothing else but a privation of Light, or a want of reflection; and wheresover this reflecting quality is deficient, there does that part look black, whether it be from a porousness of the body, as in this Instance, or in a deadning and dulling quality, such as I have observ'd in the Scoria of Lead, Tin, Silver, Copper, &c.

Next, we may also as plainly see the reason of its shining quality, and Rh