ON THE DIRECTION OF THE RADICLE AND GERMEN, ETC. 125 



The radicles of these seeds were made to point in every direction, some 

 towards the centre of the wheel, and others in the opposite direction ; 

 others as tangents to its curve, some pointing backwards, and others 

 forwards, relative to its motion ; and others pointing in opposite direc- 

 tions in lines parallel with the axis of the wheels. The whole was 

 inclosed in a box, and secured by a lock, and a wire grate was placed 

 to prevent the ingress of any body capable of impeding the motion of 

 the wheels. 



The water being then admitted, the wheels performed something more 

 than 150 revolutions in a minute; and the position of the seeds relative 

 to the earth was of course as often perfectly inverted, within the same 

 period of time ; by which I conceive that the influence of gravitation 

 must have been wholly suspended. 



In a few days the seeds began to germinate, and as the truth of some 

 of the opinions I had communicated to you, and of many others which I 

 had long entertained, depended on the result of the experiment, I 

 watched its progress, with some anxiety, though not with much appre- 

 hension ; and I had soon the pleasure to see that the radicles, in what- 

 ever direction they were protruded from the position of the seed, turned 

 their points outwards from the circumference of the wheel, and in their 

 subsequent 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 wheel. Three of these plants were suf- 

 fered to remain on the wheel, and were secured to its spokes to prevent 

 their being shaken off by its motion. The stems of these plants soon 

 extended beyond the centre of the wheel : but the same cause, which 

 first occasioned them to approach its axis, still operating, their points 

 returned and met again at its centre. 



The motion of the wheel being in this experiment vertical, the radicle 

 and germen of every seed occupied, during a minute portion of time in 

 each revolution, precisely the same position they would have assumed had 

 the seeds vegetated at rest ; and as gravitation and centrifugal force also 

 acted in lines parallel with the vertical motion and surface of the wheel, 

 I conceived that some slight objections might be urged against the con- 

 clusions I felt inclined to draw. I therefore added to the machinery I 

 have described another wheel, which moved horizontally over the vertical 

 wheels ; and to this, by means of multiplying wheels of different powers, 

 I was enabled to give many different degrees of velocity. Round the cir- 

 cumference of the horizontal wheel, whose diameter was also eleven inches, 

 seeds of the bean were bound as in the experiment which I have already 



