NATURAL PHILOSOPHY. 



ROTATION PRODUCED BY ELECTRICITY. 



AT a recent meeting of the Royal Societ}', England, an ingenious and curi- 

 ous apparatus was exhibited, displaying the rotation of a metallic sphere by 

 electricity. The apparatus was contrived by Mr. Gore, of Birmingham, who 

 states that his experiments had their origin in a phenomenon observed by 

 Mr. Fearn, of Birmingham, in his electro-gilding establishment. When a 

 tube of brass, half an inch in diameter and four feet long, was placed upon 

 two horizontal and parallel brass tubes, one inch in diameter and nine feet 

 long, and at right angles to them, and the latter connected with a long voltaic 

 battery consisting of from two to twelve pairs of large zinc and carbon ele- 

 ments, this transverse tube immediately began to vibrate, and finally to roll 

 upon the others. Acting upon this, Mr. Gore constructed a disk of wood, 

 provided with two brass rails, level, uniform, and equi-distant; on these rails 

 a hollow and very thin copper ball was placed, and the brass rails being con- 

 nected with a zinc and carbon battery, the ball began to vibrate, and pres- 

 ently to revolve. In all cases yet observed, Mr. Gore states, that the motion 

 of the ball is attended by a peculiar crackling sound at the points of contact, 

 and by heating of the rolling metal. When the apparatus was exhibited be- 

 fore the Royal Society, electric sparks were seen as the ball rolled from the 

 spectator. 



ELECTRICITY OF NERVES AND MUSCLES. 



M. de la Rive, in the third volume of his Treatise on Electricity, just pub- 

 lished, reviews the whole science of electro-physiology; and reminds practi- 

 tioners that, as the difference between the electricity of the muscles and of 

 the nerves is now clearly established, so must they be careful in applying 

 their remedies, not to waste on the muscles, which are the best conductors, 

 the electric currents intended solely for the nerves. 



ACCIDENTS BY LIGHTNING. 



From a recent foreign work, " Boudin on Medical Geography," we derive 

 the following memoranda respecting accidents from lightning. As compared 

 with the country, towns, and especially the larger and more populous ones, 

 appear to possess an immunity from accident to life by lightning. Thus, 

 between 1800 and 1851, not a single death by lightning was recorded in Paris ; 

 and in 1786 it was calculated that out of 750,000 deaths in London, during 



