AND THE ATMOSPHERE. 213 



the other proposition, which immediately fol- 

 lows ; namely, that the pressure of fluids upwards, 

 is equal to the pressure downwards, at any gi- 

 ven depth ; and that when the mass is level, the 

 whole mass will be at rest ; and that any part 

 of a fluid at rest, presses and is pressed equally 

 in all directions ? The equable pressure of 

 fluids in all directions, is proved by a very sim- 

 ple diagram, which being generally advanced 

 by the supporters of these contradictory opi- 

 nions, will, perhaps, be better understood by 

 them, than if it were one of my own. " Let 

 A. B. C. D. be a vessel of water, whose alti- 

 tude E. F. is supposed to consist of a column of 

 10, or 10,000, aqueous particles; then it is 

 evident, the first, or uppermost, particle 1. 

 can affect the next particle 2. only by its pres- 

 sure every way, which, therefore, is as 1. and 

 since the particle 2. is immoveable, and action 

 and reaction are equal and contrary ; the said 

 particle 2. will resist upwards upon the particle 

 1. with a force which is as 1; and it must evidently 

 appear, that what holds good with respect to 

 these, must hold good also with respect to all 

 the rest, in an indefinite series." 



In order, however, to reconcile contradictory 



* I quote the words of others, and, therefore, am not an- 

 swerable for the folly of ascribing action and reaction to bo- 

 dies, which are stated to be immoveable. 



