in Fluids. 349 



tion of it here given, have no existence in fact (which is 

 what I very much suspect), in that case it is evident that 

 the solution, though it would not be absolutely impos- 

 sible, would be so very slow as hardly to be perceptible. 



It would not be impossible ^ because the particles of the 

 menstruum in immediate contact with the solid, though 

 in the moment of their saturation they would have no 

 tendency to move out of their places, yet, as they would 

 by degrees necessarily give off to the undissolved part 

 of the solid a part of the Heat acquired in the chemical 

 process by which they were saturated, being condensed 

 by this loss of Heat, they would, at length, begin to de- 

 scend, and give place to other particles of the men- 

 struum ; which, in their turns, would follow them, but 

 with velocities, however, continually decreasing, on ac- 

 count of the gradual augmentation of temperature of 

 the undissolved part of the solid, and of the Heat com- 

 municated by that solid substance to the whole mass of 

 the liquid menstruum. 



Though it would, probably, be extremely difficult to 

 contrive any single experiment, from the result of which 

 a satisfactory decision of this question could be obtained, 

 yet it does not appear to be impossible to discover by 

 indirect means the principal fact on which its decision 

 must depend. 



It is a well-known fact, that, when water which holds 

 sea-salt in solution is mixed, in any vessel, with fresh 

 water, the salt will, after a short time, be found to be 

 very equally distributed in every part of the whole mass ; 

 and I believe that it has been generally considered that 

 this equal distribution of the salt is owing to the affinity 

 which is supposed to exist between sea-salt and water. 



Having doubts with respect to the existence of this 



