38 First published Paper on 'Electricity 



then, in all parts of the space Bb, the fluid will be pressed close together, 

 so that its particles shall touch each other; the space Bfi will be intirely 

 deprived of fluid; and in the space Cb, and all the rest of infinite space, 

 the matter will be exactly saturated. 



For, if the fluid is disposed in the above-mentioned manner, a particle 

 of fluid placed anywhere within the space Cb will not be impelled in any 

 direction by the fluid in Bb, or the matter in Bfi, and will therefore have 

 no tendency to move : a particle placed anywhere without the sphere /JSe 

 will be attracted with just as much force by the matter in Eft, as it is 

 repelled by the redundant fluid in Bb, and will therefore have no tendency 

 to move : a particle placed anywhere within the space Bb, will indeed be 

 repelled towards the surface, by all the redundant fluid in that space < 

 which is placed nearer the center than itself; but as the fluid in that 

 space is already pressed as close together as possible, it will not have any 

 tendency to move ; and in the space Bf$ there is no fluid to move, so that 

 no part of the fluid can have any tendency to move. 



Moreover, it seems impossible for the fluid to be at rest, if it is disposed 

 in any other form; for if the density of the fluid is not everywhere the 

 same at the same distance from the center, but is greater near b than near d, 

 a particle placed anywhere between those two points will move from b 

 towards d; but if the density is everywhere the same at the same distance 

 from the center, and the fluid in Bb is not pressed close together, the 

 space Cb will be overcharged, and consequently a particle at b will be 

 repelled from the center, and cannot be at rest : in like manner, if there is 

 any fluid in Bf$, it cannot be at rest : and, by the same kind of reasoning, 

 it might be shewn, that, if the fluid is not spread uniformly within the 

 space Cb, and without the sphere /JSe, it cannot be at rest. 



21] COR. I. If the globe BDE is undercharged, everything else being 

 the same as before, there will be a space Bb, in which the matter will be 

 intirely deprived of fluid, and a space Bfi t in which the fluid will be pressed 

 close together; the matter in Bb being equal to the whole redundant 

 matter in the globe, and the redundant fluid in Eft, being just sufficient 

 to saturate the matter in Bb : and in all the rest of space the matter will be 

 exactly saturated. The demonstration is exactly similar to the foregoing. 



22] COR. II. The fluid in the globe BDE will be disposed in exactly 

 the same manner, whether the fluid without is immoveable, and disposed 

 in such manner, that the matter shall be everywhere saturated, or whether 

 it is disposed as above described; and the fluid without the globe will be 

 disposed in just the same manner, whether the fluid within is disposed 

 uniformly, or whether it is disposed as above described. 



23] PROP. VI. PROBLEM 2. To determine in what manner the fluid will 

 be disposed in the globe BDE, supposing everything as in the last problem, 



