50 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



mon salt is mixed with an additional quantity of water, when 

 no liquefaction takes place, he remarks that this explanation 

 does not account for the loss of heat, but that part of the 

 heat disappears and becomes latent, or enters the body in 

 such a manner as to give rise to a new and permanent qual- 

 ity, namely, lower freezing-point. 21 A, IX.,7i^y, 1871, 475. 



OPPOSITE CURRENTS OF ELECTRICITY. 



It is stated by the London Athenceum that Mr. C. F. Var- 

 ley, the well-known electrician, has devised a method by 

 which four currents of electricity can be delivered simulta- 

 neously by a single wire, even in opposite directions. 



ACTION OF MAGNETISM ON GASES TRAVERSED BY ELECTRICAL 



CURRENTS. 



In a paper by MM. A. de la Rive and E. Sarasin, in the Bib- 

 liotheque Universelle, the following conclusions are announced 

 as the result of a long series of experiments upon the action 

 of magnetism on gases traversed by electrical currents: 1. 

 The action of magnetism exerted upon a portion only of an 

 electric jet traversing a rarefied gas causes an augmentation 

 of density in this portion. 2. This action exerted upon an 

 electric jet placed equatorially between the poles of an .elec- 

 tro-magnet produces in the rarefied gas an augmentation of 

 resistance proportional to the conductivity of the gas itself. 

 3. On the contrary, it causes a corresponding diminution of 

 resistance when the jet is axially between the two magnetic 

 poles. 4. When the action of the magnetism is to impress a 

 continuous movement of rotation upon the electric jet, it has 

 no influence upon the conductivity if the rotation be in the 

 plane perpendicular to the axis of the iron cylinder detaining 

 the rotation, and diminishes it considerably if the rotation 

 takes place so that the jet describes a cylinder round the 

 axis. 5. These effects do not seem to be due to variations of 

 density, but to perturbations in the arrangement of the par- 

 ticles of the rarefied gas. 12 A, July 20,230. 





