112 Setentific Intelligence. 
has succeeded in applying the principle of the Leyden jar to the elee: 
tric charge by means of the current induced in the inducing wire. 
aces of tin, where they lose a large part of their tension through the 
mutual influence across the insulating coats of varnish. 
e time, the machine increases remarkably in energy. ‘The 
poles then give stronger and longer sparks than before. 
The condenser may be conveniently placed in a horizontal position, 
a little above the electro-magnet and upon four supports of glass. M. 
Sinsteden who has described his methods in Poggendorff’s Annalen, 
also employs the condenser, but only for the induced wire, and his ap- 
in its ordinary condition, the needle of the galvanometer indicated a de- 
viation of 8°; but with the condenser, the light produced had a much. 
Following out these views, M. Chevreul examines the influence of 
the paving of streets on the salubrity of the soil when considered as an 
obstacle to the penetration of rain waters; the influence of air; of 
solar light; of empyreumatic substances derived from conduits of gas: 
of the water running from public fountains; of sulphate of lime and 
of organic matters in producing an alkaline sulphuret, etc. 
7 * This yolume, page 99. 
