232 ADVANCEMENT OF LEARNING 



there is a preponderancy, as when wood is laid upon wax; 

 or by an equal resistance, as when water is laid upon water, 

 or wood upon wood of the same kind; which is what the 

 schools pretend, when they idly imagine that bodies do not 

 gravitate in their own places. And all these circumstances 

 alter the motion of gravity; for heavy bodies move after 

 one way in the balance, and after another in falling: and, 

 which may seem strange, after one way in a balance sus 

 pended in the air, and after another in a balance plunged 

 in water; after one way in falling through water, and after 

 another when floating upon it. 



6. Inquire into the effects of the figure of the descending 

 body, in directing the motion of gravity: suppose of a figure 

 broad and thin, cubical, oblong, round, pyramidal, etc. ; and 

 how bodies turn themselves while they remain in the same 

 position as when first let go. 



7. Inquire into the effects of the continuation and pro 

 gression of the fall or descent itself, as to the acquiring a 

 greater impulse or velocity, and in what proportion and 

 to what length this velocity is increased; for the ancients, 

 upon slender consideration, imagined that this motion, 

 being natural, was always upon the increase. 



8. Inquire into the effects of distance, or the near ap 

 proach of a body descending to the earth, so as to fall 

 swifter, slower, or not at all, supposing it were to be out 

 of the earth s sphere of activity, according to Gilbert s 

 opinion; as also the effects of plunging the falling body 

 deeper into the earth, or placing it nearer the surface; for 

 this also varies the motion, as is manifest to those who work 

 in mines. 



9. Inquire into the effects of the difference of bodies, 

 through which the motion of gravity is diffused and com 

 municated; and whether it is equally communicated through 

 soft and porous bodies, as through hard and solid ones. 

 Thus if the beam of a scale were one half of wood, and the 

 other half of silver, yet of the same weight; inquire whether 

 this would not make an alteration in the scales : and again, 



