36 TRANSACTIONS OF THE [jAN. 5, 



A paper by Prof. H. Carrington Bolton was read by 

 title, 



A CATALOGUE OF CHEMICAL PERIODICALS. 



(Published in the Annals, Vol. iii., pp. 159-216.) 

 Pkof. Charles B. Waring read a paper on 



EXPERIMENTAL STUDIES ON THE GYROSCOPE, GYROSTAT AND OTHER 

 ROTATING BODIES. 



The Gyroscope is a very curious instrument, or rather it is a 

 simple little instrument which behaves in a very curious man- 

 ner, apparently violating the law of gravitation. 



It consists of a small disk, or wheel, moving freely on an axis 

 which itself is supported by a ring going around the disk and 

 axis both. On one side of the ring close by one end of the 

 axis, is a small projection or lug. The wheel is set going like a 

 top, ])y a string wound around one arm of the axis, and then 

 pulled as fast as possible. The wheel revolves very rapidly, 

 perhaps thirty times in a second. So far there is nothing- 

 strange, l)ut if one takes the thing in his hands and tries to 

 turn it, it seems to be suddenly endowed with remarkable 

 powers of resistance. There seems to be something uncanny 

 about it. If now, while yet rapidly rotating, the lug (in the 

 under side of which, by the way, there is a small, round depres- 

 sion), be placed on a pointed standard, the instrument will keep 

 itself out straight (horizontal) in the air and begin to revolve 

 slowly around the point, always going in the direction of the 

 under side of the disk. At the same time it drops very slowly 

 — one-tenth of an inch or less in a second (more or less accord- 

 ing to certain circumstances). It seems as if -it had lost its 

 weight, or as if gravity no longer acted on it, but if placed on 

 scales while in this condition, it will be found to weigh exactly 

 as much as when not moving. 



If a string be attached to the lug, and the Gyroscope lifted 

 off its support, it will go up into the air still at right angles to 

 gravity, and still moving slowly horizontally around the end of 

 the string. If it be jerked rapidly up, or dropped down, it 

 continues its motion and position with the most perfect indif- 

 ference. If another string be attached to the opposite end of 

 the axis, and the thing be lifted by that, it will instantly begin 

 to rotate (horizontally) in the opposite direction. E\erything 

 else will be as before. 



