C. B. WARRING. 101 



8. If, while the instrument is slowly revolving around 

 the fixed point, and standing out horizontally, as if by 

 some magic gravitation had ceased, it be placed upon 

 scales, the whole will weigh just the same as if the wheel 

 was at rest. The weight is in some way transferred from 

 the centre of gravity to the point of support. 



The following is an interesting mode of showing this : 



Put the standard in one pan of a pair of scales, and 

 counterpoise it so that its weight may be left out of con- 

 sideration. Place the gyroscope with one end on the 

 standard, and support the other by a thread from the 

 ceiling. If ring and disk together weigh, for example, 

 two pounds, the scales, of course, will indicate a weight 

 of one pound. Whether the wheel is rotating, or not, 

 the scales will indicate one pound, and there will be no 

 horizontal movement. Now set the wheel in rapid 

 motion and then cut the string. The instrument does 

 not fall. Gyration 1 at once commences, and the scales 

 indicate two pounds. 



Let the lug be prolonged into an arm, as in fig. 2, with 

 a movable weight, w. 2 So long as the gyroscope is the 

 heavier, all the preceding phenomena can be produced 

 with this form. If, however, the weight is placed so 

 that neither side is the heavier, then there will be no 

 gyration. If the weight end is the heavier the gyration 

 re-commences, but goes backward and the wheel rises. 

 The arm is 11 inches long and graduated to 2 oz. or 4 oz. 

 notches, according as the weight is applied under the cen- 

 ter of the wheel or at the hook in the free end. The 

 screw, s, is of fine steel ending in a fine, hard, highly- 

 polished point, resting in a cup of polished, hard steel. 



Mr. Wheatstone, in a paper read before the Royal So- 



1 Gyrate and gyration, as used in this paper indicate the lateral or horizontal movement 

 around the fixed point, while rotate and rotation have reference to the revolution of the 

 wheel on its axis. 



2. The wheel of my instrument is 5% inches across, and weighs 3 lbs. The ring and arm 

 weigh 1 lb. 6 oz., and the weight, w, 1 lb. 12 oz. 



85 



