364 Mr. Whelpley on the Idea of an Atom. 



lengths of the axes) and ils bulk, is certain; but, to establish 

 such a relation, the facts of chemistry must be appealed to. 



The temperature, at which atoms may develope the three 

 axes of solidity, is not the only condition of their solidification; 

 for it is well known that the solids of many substances occupy 

 more space, than the liquids from which they crystallize ; and 

 water may be cooled without freezing, far below its freezing 

 point ; and when any part, of such a mass of water, begins to 

 form crystals, it raises the temperature of the rest. It follows, 

 that, in general, nuclei in contact ca mi ot develope their solid axes, 

 (i. e. cannot increase the intensity of their polarities in those 

 axes,) without diminishing to an equal degree that of bodies in 

 imm,ediate contact with them; and this diminution is balanced 

 by an increase of bulk, (i. e. of sensible heat,) so that freezing 

 liquids actually cause an expansion (heating) of bodies in con- 

 tact with them. It is difficult to show the nature of this relation, 

 between the increase of axial intensity in a solid, and the dimi- 

 nution (or cooling) of its mass ; meanwhile, that there is such a 

 relation, is evident. 



Electricity. 



That the polar forces of gaseous nuclei are the sa,me with 

 those of solids, is proved by the electric excitation of air by elec- 

 trified surfaces. 



The "conduction" of electricity, though it occupies time, is 

 clearly not a conduction in the usual sense of the word, but is the 

 restoration of ati equilibrium. An insulated electrified body is 

 known to be in the electric relation, not only to objects near, but 

 to the whole of space ; for its influence diminishes as the distance 

 square, inversely, in the manner of gravitation. The excitation 

 of one body by the presence of another, is effected by the inter- 

 vention of air ; for it has been long known, that a rare atmos- 

 phere suffers the passage of electric influences, more easily than 

 a dense one. If a space could be freed of air. it would therefore 

 permit the instantaneous restoration of the electric equilibrium 

 through its vacuum ; and magnets act upon each other through 

 all obstacles ; — considerations which show, that the polar forces 

 of every nucleus are in a relation of equilibrium with the forces 

 of every other atom near or far. But this relation is one of in- 

 tensity, and of this intensity there are two kinds ; corresponding 



