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show the essential parts more in detail. The reference letters are the same in each illustration. A B is a mahogany board, 36 inches long by 9^ inches wide, and 1 inch thick. It is suspended at the end, B, by a spring balance, C,
furnished with an automatic register, D. The balance is suspended from a very firm tripod support, E.
The following piece of apparatus is not shown in the figures. To the moving index, o, of the spring balance, a
grooved frame carrying a flat box similar to the dark box of a photographic camera. This box is made to travel by clock-work horizontally in front of the moving index, and it contains a sheet of plate-glass which has been smoked over a flame. The projecting steel point impresses a mark on this smoked surface. If the balance is at rest, and the clock set going, the result is a perfectly straight horizontal line. If the clock is stopped and weights are placed on the
end B of the board, the result is a vertical line, whose length depends on the weight applied. If, whilst the clock draws the plate along, the weight of the board (or the tension on the balance) varies, the result is a curved line, from which the tension in grains at any moment during the continuance of the experiments can be calculated.
The instrument was capable of registering a diminution of the force of gravitation as well as an increase; registrations of such a diminution were frequently obtained. To avoid complication, however, I will only here refer to results in which an increase of gravitation was experienced.
The end B of the board being supported by the spring balance, the end A is supported on a wooden strip, F, screwed across its lower side and cut to a knife edge (see Fig. 4). This fulcrum rests on a firm and heavy wooden stand, G H. On the board, exactly over* the fulcrum, is placed a large glass vessel filled with water, I. L is a massive iron stand, furnished with an arm and a ring, M N, in which rests a hemispherical copper vessel perforated with several holes at the bottom. ,
The iron stand is 2 inches from the board A B, and the arm and copper vessel, M N, are so adjusted that the latter dips into the water \\ inches, being 5\ inches from the bottom of I, and 2 inches from its circumference. Shaking or striking the arm M, or the vessel N, produces no appreciable mechanical effect on the board, A B, caPabl<: of affecting the balance. Dipping the hand to the fullest extent into the water in N does not produce the least appreciable action on the balance. X
As the mechanical transmission of pov^'is bYthis means entirely cut off between the copper vessel aY^ the board A B, the power of muscular control is therebV completely eliminated. "\\
For convenience I will divide the experiments flf^0 grouPs I, 2, 3, &c, and I have selected one special inK*an.ce"! each to describe in detail. Nothing, however, is meV1-1011 which has not been repeated more than once, and in" some cases verified, in Mr. Home's absence, with another piP': possessing similar powers.
There was always ample light in the room where experiments were conducted (my own dining-room) to all that took place.
Experiment I.—The apparatus having been properly a justed before Mr. Home entered the room, he was brought in, and asked to place his fingers in the water in the coppe^ vessel, N. He stood up and dipped the tips of the fingers of his right hand in the water, his other hand and his feet being held. When he said he felt a power, force, or influence, proceeding from his hand, I set the clock going, and almost immediately the end B of the board was seen to descend slowly and remain down for about io seconds; it then descended a little further, and afterwards rose to its normal height. It then descended again, rose suddenly, gradually sunk for 17 seconds, and finally rose to its normal height, where it remained till the experiment was concluded. The lowest point marked on the glass was equivalent to a direct pull of about 5000 grains. The accompanying figure (5) is a copy of the curve traced on the glass.
• In my first experiments with this apparatus, referred to in Professor Stokes's letter and my answer (page 479), the glass vessel was not quite over the fulcrum, but was nearer B.
Experiment II.—Contact through water having proved to be as effectual as actual mechanical contact, I wished to see if the power or force coulJ affect the weight, either through other portions of the apparatus or through the air. The glass vessel and iron stand, &c, were therefore removed,
Scale of Seconds.
C J 10 E0 33 40 50 60
III 111 1 . I I I I I
Tiie horizontal scale of seconds shows the time occupied in the movements,
the experiment lasting one minute. The vertical scale shows the tension in
as an unnecessary complication, and Mr. Home's hands were placed on the stand of the apparatus at P (Fig. 2). A gentleman present put his hand on Mr. Home's hands, and his foot on both Mr. Home's feet, and I also watched him closely all the time. At the proper moment the clock was
again set going; the board descended and rose in an irregular manner, the result being a curved tracing on the glass, of which Fig. 6 is a copy.
Experiment III.—Mr. Home was now placed one foot from the board A B, on one side of it. His hands and feet
were firmly grasped by a bystander, and another tracing, of which Fig. 7 is a copy, was taken on the moving glass plate.
Experiment IV.—(Tried on an occasion when the power was stronger than on the previous occasions). Mr. Home was now placed 3 feet from the apparatus, his hands and feet being tightly held. The clock was set going when he gave the word, and the end B of the board soon descended, and again rose in an irregular manner, as shown in Fig. 8.
The following series of experiments were tried with more delicate apparatus, and with another person, a lady, Mr. Home being absent As the lady is non-professional, I do
not mention her name. She has, however, consented to meet any scientific men whom I may introduce for purposes of investigation.
A piece of thin parchment, A, Figs. 9 and 10, is stretched tightly across a circular hoop of wood. B c is a light lever turning on D. At the end B is a vertical needle point touching the membrane A, and at C is another needle point, projecting
Fig. 9. (Plan.)
horizontally and touching a smoked glass plate, E F. This glass plate is drawn along in the direction H G by clockwork, K. The end B of the lever is weighted so that it shall quickly follow the movements of the centre of the disc, A. These movements are transmitted and recorded on the glass plate E F, by means of the lever and needle