472 Miscelluneous Intelligence. 



3. On the tramference of Ponderable Matter in Electric Dis- 

 charges, by M. Fusinieri. — ^This philosopher has made numerous 

 experiments on this subject, but we think it sufficient to quote the 

 following- only. Two large Leyden jars were charged, one of which 

 had a ball of silver, connected with its knob by a silver wire; a 

 polished dish of copper, nine centimetres in diameter and two-thirds 

 of a millimetre in thickness, was then held against the ball of the 

 discharging rod, and the discharge made from the silver ball, 

 throug-h the plate to the brass ball, with which it was in contact. 

 The distance was six or eight lines, such was the length of spark, 

 and the following were the results : — 1, A red stain (oxide of cop- 

 per), with a greenish portion (oxide of silver), and white spots, 

 (silver), was formed on the face of the disc, opposite the silver ball. 

 2. A stain, more or less green, existed on the other side of the 

 plate, where it was in contact with the brass ball. 3. The brass 

 ball had a white stain, at the point of contact. 4. Finally, the 

 ball of silver had traces of oxide of copper. Besides these etfects, 

 the copper and brass w^ere roughened at the points of discharge. 



In another experiment, a ball of gold and a disc and discharger 

 of silver were used with the former two jars. The disc was placed 

 in contact with the ball of silver ; a gold stain, a centimetre in 

 diameter, was obtained on the external face of the disc, although the 

 electric spark had to pass a distance of from two to four centimetres 

 from the gold to the silver. This beautiful stain was like a very 

 thin film of gold; in the course of some minutes, it became more 

 rare, and totally disappeared in the course of some days, — an effect 

 which sufficiently indicates that the gold had been reduced to a 

 volatile state. There was also a stain of gold on the ball of silver, 

 and a stain of silver on the ball of gold. 



Another experiment was made: after having covered one of the 

 faces of the silver-plate with wax, and made a hole in the wax, 1 J 

 millimetres in diameter; the face not covered received a stain of 

 volatile gold, as in a former experiment; but on the face covered 

 with wax, there was a layer of gold of more thickness and solidity, 

 as it did not disappear by spontaneous evaporation. 



It is supposed, that these experiments prove the transportation 

 of ponderable matter by the electric spark. The subject being 

 reduced to such a state of division as to become volatile. After 

 this it is supposed, that the light of the spark is due to the presence 

 of molecules of ponderable matter detached by the electricity from 

 the hardest bodies. The diversity of colour in the spark is in the 

 same way supposed to be readily explicable. The light observed 

 in vacuo between the poles of the voltaic light are due, without 

 doubt, it is said, to solid particles carried by the current. The 

 smell occasioned by the electric sparks of our machines, and by 

 lightning, is considered as the odour of the transported matter. — 

 Gior, diFisica, J825, p. 450. 



4. New Phenomena produced hy Vapour ^ observed by M. Clement 



