94 THE SEVEN FOLLIES OF SCIENCE 



quickly frozen. In this way it was easy to make a ham- 

 mer-head of frozen mercury and drive a nail with it. 



Another very interesting experiment was the freezing of 

 a slender triangular bar of mercury which might be twisted, 

 bent, and tied in a knot. This was done by folding a long 

 strip of very stiff paper so as to make an angular trough 

 into which the mercury was poured. This trough was then 

 carefully leveled and a mixture of solid carbonic acid and 

 ether was placed over the metal in the usual way. In a few 

 seconds the mercury was frozen quite solid so that it could 

 be lifted out by means of two pairs of wooden forceps and 

 bent and knotted at will. But the most striking part of the 

 experiment was the melting of this bar of mercury by 

 means of a piece of ice. The moment the ice touched the 

 mercury, the latter melted and fell down in drops in the 

 same way that a bar of lead or solder melts when it is 

 touched with a red-hot iron. 



The melted mercury was allowed to fall into a tall ale-glass 

 of water, the temperature of which had been reduced as 

 nearly as possible to the freezing point. When the mercury 

 came in contact with the cold water, the latter began to freeze 

 and by careful manipulation it was possible to freeze a tube 

 of ice through the center of the column of water. The 

 effect of this under proper illumination was very striking. 



Owing to the fact that the specific heat or thermal ca- 

 pacity of mercury is only about one-thirtieth of that of 

 water, it requires a considerable amount of melted mercury 

 to produce the desired result. 



But these processes do not enable us to fix mercury in 

 the alchemical sense ; the accomplishment of that still 

 remains an unsolved problem, and it is more than likely 

 that it will remain so, 



