_B._ If that were so, it would still be ice, though also crystal: which cannot be, because crystal is heavier than water, and therefore much heavier than ice. _A._ Is there then no transubstantiation of bodies but by mixture? _B._ Mixture is no transubstantiation. _A._ Have you never seen a stone that seemed to have been formerly wood, and some like shells, and some like serpents, and others like other things? _B._ Yes. I have seen such things, and particularly I saw at Rome, in a stone-cutter’s workhouse, a billet of wood, as I thought it, partly covered with bark, and partly with the grain bare, as long as a man’s arm, and as thick as the calf of a man’s leg; which handling I found extreme heavy, and saw a small part of it which was polished, and had a very fine gloss, and thought it a substance between stone and metal, but nearest to stone. I have seen also a kind of slate painted naturally with forest-work. And I have seen in the hands of a chemist of my acquaintance at Paris, a broken glass, part of a retort, in which had been the rosin of turpentine, wherein though there were left no rosin, yet there appeared in the piece of glass many trees; and plants in the ground about them, such as grow in woods; and better designed than they could be done by any painter; and continued so for a long time. These be great wonders of nature, but I will not undertake to show their causes. But yet this is most certain, that nothing can make a hard body of a soft, but by some motion of its parts. For the parts of the hardest body in the world can be no closer together than to touch; and so close are the parts of air and water, and consequently they should be equally hard, if their smallest parts had not different natural motions. Therefore if you ask me the causes of these effects, I answer, they are different motions. But if you expect from me how and by what motions, I shall fail you. For there is no kind of substance in the world now, that was not at the first creation, when the Creator gave to all things what natural and special motion he thought good. And as he made some bodies wondrous great, so he made others wondrous little. For all his works are wondrous. Man can but guess, nor guess farther, than he hath knowledge of the variety of motion. I am therefore of opinion, that whatsoever perfectly homogeneous is hard, consisteth of the smallest parts, or, as some call them, atoms, that were made hard in the beginning, and consequently by an eternal cause; and that the hardness of the whole body is caused only by the contact of the parts by pressure. _A._ What motion is it that maketh a hard body to melt?