Relations of the Atmosphere. 357 
would, by the laws of diffusion and static equilibrium, be felt 
everywhere throughout the universe. 
The precipitation of water at the surface of a cooling globe, 
and its chemical or mechanical fixation there, would thus 
diminish the proportion of gaseous water throughout all space. 
he oxygen liberated in the growth of terrestrial vegetation 
would be shared with the remotest spheres, while the condensa- 
tion of carbonic dioxide at the surface of our own or any other 
planet, would not only bring in a supply of this gas from the 
atmospheres of other bodies, but by reducing the total amount 
of it, would diminish, pro tanto, the barometric pressure at the 
surface of this and of all other worlds. L 
he hypothesis here advanced is not wholly new. Sir 
William R. Grove, in 1842, suggested that the medium of light 
and heat may be “a universally diffused matter,” and subse- 
uently, in 1848, in his celebrated Essay on the Correlation of 
hysical Forces, in the chapter on Light, concludes, with regard 
ere 
have b Ww. : 
1870 published his very ingenious work entitled “The Fuel of 
the Sun,’* which is based on a similar conception, without 
citing in support of it the high authority of Grove. The solar 
heat, according to Williams, is maintained by the sun’s con- 
6 * See also Williams on The Radiometer and its Lessons, Quart. Jour. Science, 
et., 1876. 
Am. Jour. So1.—Turrp SERiIEs, VoL, XIX, No. 113.—May, 1880. 
25 
