1821.] Fhccriomena of Heat, Gases, Gravitation, B^c. 279'': 



pression, and destroy it by sudden rarefaction; and any two^ . 

 having ever so small a communication, would quickly and* 

 equally intermix. : 



Besides these, other properties equally consistent and gratify- 

 ing, presented themselves ; but as these were merely loose views - 

 of the subject, I soon resolved to examine it more rigorously, arid 

 to try if 1 could not bring it to the test of mathematical laws* . 

 In this, however, I met with a difficulty considerably superior ta 

 any I had yet encountered in the course of my analysis, and ^ 

 which, before 1 overcame it, gave me more real uneasiness than, 

 perhaps, it can be imagined it should. But the truth is, my 

 views of the subject expanded so much as I proceeded that even 

 in this early stage I fancied I perceived, in the solution of the 

 probletii I was about, not only the discovery of the cause ofgra- 

 vitation, but also of the causes of all the other phsenomena of^: 

 nature; and my thoughts were, therefore, turned upon it with , 

 an intenseness and anxiety which I never before experienced,,, 

 and which can scarcely be appreciated except by those who have 

 been placed in a similar situation. To meet now, therefore,. 

 when 1 thought I had almost completed the discovery, with an 

 , obstacle which it baffled my utmost efforts to surmount, and^ 

 which threatened destruction to the fabric I had so laboriously 

 endeavoured to raise, was a shock I had hardly philosophy- 

 enough to withstand. How^ever, as I had proceeded so far, and . 

 had been so much led away by the seducing coincidence of the 

 consequences of my theory with phsenomena, I determined to 

 examine it thoroughly, and, if I should find it erroneous, to pub- 

 lish it together With the illustration of its errors, that if it could 

 do no dlher good, it might serve for a beacon to prevent others 

 from running against the rock on which my hopes and expecta- 

 tions had been wrecked. 



The obstacle to which I allude is this : I saw directly I began ^ 

 to consider circumstances attentively, that if the constitution of 

 things be such as I supposed, the ultimate atoms of all bodies, 

 and, therefore, the particles of these gases, which I looked upon 

 to be no more than these ultimate atoms, must be absolutely 

 hard ; they must admit of no breaking, splitting, shattering, or 

 any impression whatever ; and yet if the gases are to maintain 

 their elastic property, and this property be the result of the par- 

 ticles mutually impinging on one another and the sides of the 

 containing vessel, the particles, or atoms, must likewise be 

 elastic ; that is, they must be soft ; for elasticity, according to 

 the ideas we have of it, is nothing but active softness. There- . 

 fore, it appeared to me that the ultimate atoms ought to possess 

 two properties in direct contrariety, hardness and softness, 

 which is manifestly impossible. 



Having arrived at this conclusion, which appeared to render, 

 the probability of success of all future inquiries in this track 

 desperate, it might be supposed that ray efforts would have ter^ 



