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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 circumference of the 
horizontal wheel, whose diameter was also eleven inches, seeds of the bean 
were bound as in the experiment which I have already described, and it 
was then made to perform 25 0 revolutions in a minute. By the rapid mo¬ 
tion of the water-wheel much water was thrown upwards on the horizontal 
wheel, part of which supplied the seeds upon it with moisture, and the 
remainder was dispersed, in a light and constant shower, over the seeds in 
the vertical wheel, and on others placed to vegetate at rest in different parts 
of the box. 
Every seed on the horizontal wheel, though moving with great rapidity, 
necessarily retained the same position relative to the attraction of the earth; 
and therefore the operation of gravitation could not be suspended, though 
it might be counteracted, in a very considerable degree, by centrifugal force: 
and the difference I had anticipated between the effects of rapid vertical 
and horizontal motion, soon became sufficiently obvious. The radicles 
pointed downwards about ten degrees below, and the plumes as many 
degrees above the horizontal line of the wheel’s motion; centrifugal force 
having made both to differ 80 degrees from the perpendicular direction each 
would have taken, had it vegetated at rest. Gradually diminishing the 
rapidity of the motion of the horizontal wheel, the radicle descended more 
perpendicularly, and the plumes grew more upright; and when it did not 
perform more than 80 revolutions in a minute, the radicle pointed about 
45 degrees below, and the plume as much above the horizontal line; the 
one always receding from, and the other approaching to, the axis of the 
wheel. 
I would not, however, be understood to assert that the velocity of 250, 
or of 80 horizontal revolutions in a minute, will always give accurately the 
degrees of depression and elevation of the radicle and plume which I have 
mentioned; for the rapidity of the motion of my wheels was sometimes 
diminished by the collection of fibres of conferva against the wire grate; 
which obstructed in some degree the passage of the water: and the ma¬ 
chinery, having been the workmanship of myself and my gardener, cannot 
be supposed to have moved with all the regularity it might have done, had 
it been made by a professional mechanic. But I conceive myself to have 
fully proved that the radicles of germinating seeds are made to descend, and 
