170 OUTLINES OF NATURAL PHILOSOPHY. 



ter in one vessel, and that in another, the surfaces 

 of both will come to be at the same level before the 

 water is at rest ; or if there is not water sufficient to 

 bring both to a level, the whole will be accumulated 

 in, the lowest. 



If water is permitted to flow freely from one vessel 

 to another, it will never be at rest til it is the lowest 

 possible. 



249. The fluid contained in any vessel, being at 

 rest, and subjected to the sole action of gravity, 

 any particle of it is pressed in all directions, (ver- 

 tically, horizontally, and obliquely,) by the same 

 force, viz. the weight of the column of water per- 

 pendicularly incumbent on it. 



BOSSUT, Hydrodynamique, vol. i. 523. 



250. If the fluid contained in any vessel be at 

 rest, and subjected to the action of gravity only, the 

 pressure on an indefinitely small area, at any point 

 of the bottom or sides, is perpendicular to the 

 plane of that area, and equal to the weight of a 

 vertical column of the fluid, standing on it as a 

 base, and reaching to the surface. 



Hence the pressure on any part in the bottom or 

 sides of a vessel, depends entirely on the depth of 

 the fluid at that point, and not at all on the extent 

 of the fluid in a horizontal direction. 



2151. The 



