Drops of water and shot compared.
Put your finger on a shot, and it remains shot still. Why is it not gone like the round drop of water? Because its particles attract each other so much that they are not easily separated. A mere touch will separate the particles of the drop of water, and make them roll about any way; but you can not do this to the shot without heating it very hot. You can melt it, and then it will be, like the water, a liquid. Its particles now attract each other but little, just as the particles of water do. And then, again, you can freeze the water, and its particles attract each other like the particles of the solid shot.
Quicksilver.
In some fluids the particles attract each other more strongly than they do in others. And the more they attract each other, the better they keep their drop shape. Pour a very little quicksilver on a flat surface. See the round drops of it roll about! How well they keep their shape! If you touch them you do not spoil them, as you do a drop of water when you touch it. If you break one as you touch it, its parts make only so many little drops or balls. Why is this? It is because the particles of the quicksilver attract each other so much more than the particles of water do. They are so attractive to each other that they are disposed to keep together in little companies.
Drops on leaves.
You sometimes see drops of water on the leaves of plants more round and separate than you see them on window-panes. They roll about like the little balls of quicksilver. See the reason of this. The particles of the drop like each other, as we may say, better than they do the leaf. They are more ready to stick together than they are to stick to the leaf, and so they roll about on it like little balls. As you see the drops on the glass, they are not round, because the particles on one side stick to the glass—that is, they are attracted by it; but the leaf does not attract the particles so much as the glass does, for it lets them keep together in a round form. There is a difference between different leaves about this. On some, the drops of water act as they do on the window-pane, and on others they do as I have just told you; and then, on the same leaves, the drops act differently at different times.
Oil on water.
If you pour a little oil on water, you see the oil floating in drops. This is for the same reason that water stands in round drops on some leaves. The water has no attraction for the oil, and so the particles of the oil hold together in little companies on the surface of the water. It is different when oil is spilled upon cloth or wood. It has so much attraction for them that it mingles up with their fibres, instead of forming into round companies as it does on the water.
How shot are made.