108 0)1 the Theory of mixed Gases. 



ill expanding along a conductor : this supposition is contra- 

 dicted by various appearances, from which the following one 

 is selected, — agitation is known to accelerate the union of 

 oxygen and nitrous gas. The quantity of A then, which 

 has been newly admitted, will remain at first unmixed with 

 B; but it w^ill act immediately with a repulsive force upon 

 kindred particles difilised through the compound C. This 

 new modification of A will not preserve the density of its 

 parts every where in a constant ratio to the density of the 

 corresponding parts of B ; and this change will disjoin the 

 centres of gravity of A and B, which has been proved above. 

 But when these points are placed apart, the separate equi- 

 libria of the fluids cease to exist, which has also been de- 

 monstrated before : therefore A and B begin to act and re- 

 act mutually ; which circumstance disturbs the necessary 

 adjustment of C, and forces it to assume another character. 

 It has also been proved in a former paragraph, that the two 

 fluids will act upon each other in the manner of elastic bodies, 

 even when the heterogeneous particles are supposed to be 

 mutually inelastic j Consequently A and B will begin to obey 

 the law of their specific gravities as soon as their centres of 

 gravity are separated by introducing into the space occupied 

 by C, a fresh quantity of A or B : in consequence of this 

 alteration the cciUre of gravity of the heavier fluid will begin 

 to descend, while that of the lighter moves upwards. When 

 once the centres of two gases are placed apart, their separa- 

 tion will become permanent ; because, when at a distance, 

 they are urged in opposite directions by a force resulting 

 from the difference of the specific weights of the two fluids ; 

 and this contrariety of efforts must continue so long as the 

 two centres are disjoined ; consequently this opposition of 

 force must be lasting, seeing nothing can put an end to it 

 hut an union, which it will always prevent. Nor can the 

 nuitual repulsion of the constituent particles of each gas, 

 considered apart, in any manner promote the junction of 

 the centres of gravity of the two fluids, because the action 

 and re-action of a number of bodies amongst themselves do 

 not alter the state of their common centre of gravity, whe- 

 ther it be at rest or in motion : so that A and B are under 

 4 the 



