244 GRAVITY AND LEVITY 



portion as the squares of the distances from the 

 earth decrease ; every fact of which we have 

 any knowledge, falsifies the assertion, and 

 establishes, in a manner the most decisive, the 

 truth of the contrary proposition; namely, that 

 the gravitation, or weight of bodies, increases 

 in proportion as the squares of the distances 

 from the earth increase. 



It is owing to this increase of density which 

 water acquires, in relation to the rarity of the air 

 in the upper regions, that we behold it descend 

 from the medium above, to the plane surface, 

 in the form of rain, of snow, and of hail ; 

 that water confined in a bucket, suspended 

 in the air, presses not only upon the bot- 

 tom, but upon the sides also of the bucket, 

 in proportion to the quantity of water in it. 

 The same effects take place upon the flood- 

 gates, by which water in docks and canals 

 is confined, when the pressure of the water 

 within, is only resisted by the medium of air 

 without: and it is a well known fact, which I 

 have myself ascertained, that if a bottle full of 

 air, closely corked up, is sunk into the sea by 

 means of a heavy weight attached to it, that 

 the pressure of the water will overcome not 

 only the resistance of the air in the bottle, but 

 of the cork also, and force it into the bottle. I 

 have no doubt, that if the cork had wires passed 



