122 D. Boboulieff—Dissipation of Electricity in Gases. 
tried at different sae prove that gases even of the — 
density, and under the pressure of even less than 70™™, c 
become under serif conditions conductors of electricity, aie 
the first three of the above classes of electrical discharge may 
be observed through them ;* but an absolute vacuum does not 
conduct electricity. 
On the other hand, it is impossible to deny all reaction on 
the part of the air, which is illustrated, for instance, by the 
movement of “ Franklin’s wheel.” But such a reaction may 
be derived from such atoms only as, after Saari electricity 
by contact with the electrified body, are repelled from it; of 
course, the magnitude of such reaction is very inconsiderable,S 
but nevertheless it is ee by the other manifestation, 
that is, the loss of the electri 
he atoms having oie from the body a portion of its 
electricity, carry it away as they retire, and distribute it to other 
bodies, either electricized with an opposite electricity or having 
ome direct connection with the earth. This constitutes in gen- 
ess of the loss of electricity by the agency of the 
ies, or the partial dissipation. Such, at least, is the opinion 
of almost all.| nt present, when the new theory of the con- 
stitution of gases is acce , such an explanation of the origin 
of electrical Saeipation’ inspires hope that the subsequent devel- 
‘opment of electrical statics will aid in explaining the electrical 
manifestations observed in gases, and particularly the Lapse Fe 
of electricity, whether by sparks or by silent discharge; and the 
dependence of the electrical conductibility of the gases on the 
atmospheric pressure 
Accepting the hypothesis of atomic motions in gases, it will 
easy to demonstrate that the dissipation of electricity depends 
on the pressure of the gas; and if we disregard certain circum- 
stances we will find that, 
1. Dissipation follows according to Coulomb’s law. 
2. The grey of dissipation, », is inversely proportional 
to the square root of the absolute temperature of the gas. 
3. That it is proportional to the pressure of the gas. 
4, That it depends on the nature of the gas. 
* Reiss, Reibungs electricitdt, B. i, pp. 39, 40; Morren, Pogg. Ann., B. 130, 
pp. 631, 633. 
¢ Reiss, Rebungs electricitét, B. i, pp. 39,42; Alvergniat, C. R., oe xiv, 
p. 963; Pogg. Ann., cxxxiii, p. 191 ; Willner, P Pogg. Ann., exxxiii, p. 
t In a vacuum this does not move —Tomlinson, Phil. Mag. (4 
f 
Ueber die gesetzmassig- 
£ Math., xi, pp. 348, 349; Matteuci, Memoire sur la propagé 
tion do Pelectricité, Aimn. de Ohiae et de'Pipe: (8) xxvii, p. 171. 
