Page:Vitruvius the Ten Books on Architecture.djvu/253

215

1. now proceed to explain the nature of cinnabar. It is said that it was first found in the Cilbian country belonging to Ephesus, and both it and its properties are certainly very strange. First, before getting to the vermilion itself by methods of treat­ment, they dig out what is called the clod, an ore like iron, but rather of a reddish colour and covered with a red dust. During the digging it sheds, under the blows of the tools, tear after tear of quicksilver, which is at once gathered up by the diggers.

2. When these clods have been collected, they are so full of moisture that they are thrown into an oven in the laboratory to dry, and the fumes that are sent up from them by the heat of the fire settle down on the floor of the oven, and are found to be quicksilver. When the clods are taken out, the drops which re­main are so small that they cannot be gathered up, but they are swept into a vessel of water, and there they run together and combine into one. Four pints of it, when measured and weighed, will be found to be one hundred pounds.

3. If the quicksilver is poured into a vessel, and a stone weigh­ing one hundred pounds is laid upon it, the stone swims on the surface, and cannot depress the liquid, nor break through, nor separate it. If we remove the hundred pound weight, and put on a scruple of gold, it will not swim, but will sink to the bottom of its own accord. Hence, it is undeniable that the gravity of a substance depends not on the amount of its weight, but on its nature.

4. Quicksilver is a useful thing for many purposes. For in­stance, neither silver nor copper can be gilded properly without it. And when gold has been woven into a garment, and the gar­ment becomes worn out with age so that it is no longer respect­able to use, the pieces of cloth are put into earthen pots, and burned up over a fire. The ashes are then thrown into water and