D. Boboulief— Dissipation of Electricity in Gases. 121 
quantity of vapor in the given volume remains the same. The 
coeficient of dissipation* increases with the increase of the 
quantity of vapor. 
Warburg: “Damp air does not cause greater dissipation than 
dry air.” 
8. Influence of the pressure. 
Matteuci (p. 415): “The quantity of electricity that may be 
retained on the surface of an isolated conductor depends on the 
density of the surrounding air. In a vacuum this quantity is 
nothing. The dissipation in dry air diminishes with the dimi- 
nution of the density.” : 
Warburg (p. 599): “The coefficient of dissipation sensibly 
diminishes when the pressure falls from 760™" down to 380™™, 
and at the pressure of 70™™" is less than one-third of what it 
was at 760™™,” 
9. Influence of various gases. 
Matteuci (p. 408): “In the air, hydrogen and carbonic acid, 
dry and pure, having the same pressure and temperature, the 
dissipation is the same.” : 
Warburg: “ Dissipation is the same in the air and carbonic 
acid, but in hydrogen one-half as great.” 
10. Influence of tobacco smoke, ete. 
Dellmann (p. 846): “Dissipation diminishes in the presence 
of tobacco smoke.” ; ; 
_ Warburg (p. 594) supposes “that the hard particles floating 
In the air exercise some influence.” 
Not only certain authorities in physical sciences, but even 
ical re es, sustain the 
ver vessel, 
an 
with an electricity of an opposite sign. But many experiments 
* Charault says, the dissipation in both cases decreases with the volume, thus: 
a= 
+ De la Rive, Traite de l'Electricité, T. i, p. 121. 
