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body falling near a high mountain, is a little bent 

 out of the perpendicular direction by the attraction 

 of the mountain, as has been shewn by the experi- 

 ments of Dr. Maskelyne on Schehallien. 



Gravitation has a very important influence on 

 the growth of plants ; and it is rendered probable, by 

 the experiments of Mr. Knight, that they owe the pe- 

 culiar direction of their roots and branches almost en- 

 tirely to this force. 



That gentleman fixed some seeds of the garden, 

 bean on the circumference of a wheel, which in one 

 instance was placed vertically, and in the other hori- 

 zontally, and made to revolve, by means of another 

 wheel worked by water, in such a manner, that the 

 number of the revolutions could be regulated ; the 

 beans were supplied with moisture, and were placed 

 under circumstances favourable to germination. The 

 greatest velocity of motion given to the wheel was 

 such, that it performed 25O revolutions in a minute. 

 It was found that in all cases the beans grew, and that 

 the direction of the roots and stems was influenced by 

 the motion of the wheel. When the centrifugal force 

 was made superior to the force of gravitation, which 

 was supposed to be done when the vertical wheel per- 

 formed 1 50 revolutions in a minute, all the radicles, 

 in whatever way they were protruded from the po- 

 sition of the seeds, turned their points outwards from 

 the circumference of the wheel, and in their subse- 

 quent growth receded nearly at right angles from its 

 axis ; the germens, on the contrary, took the opposite 

 direction, and in a few days their points all met in 

 the centre of the wheel. 



