C. B. WARRING. 129 



previous case, each particle in both the instruments went 

 down, but on reversal all helped to make the upward 

 force which tended to keep the instrument up. Suppose 

 we attach a load of say eight ounces to a heavy gyro- 

 scope, and an equal amount to a light one, the former 

 will show greater, power of resistance. The resistance 

 comes from the momentum of the wheels, section by 

 section, as has been shown. The momentum of the light 

 wheel is less than that of the heavy wheel, yet it has, in 

 proportion to its weight, more work to do. The momen- 

 tum of the light wheel divided by its mass and load, or, 

 m+j^aj , is less than n °^ ad , where m equals mass of small 

 wheel, and n m the mass of the large one, and v, the 

 falling velocity of each. 



It follows that a load of two ounces will make the 

 gyration and descent more rapid than would a load of 

 one ounce, and so on ; but, of course, not twice as rapid. 



We may also conclude that a heavy wheel has greater 

 stability, i. e., power of resisting a push, or a pull, or 

 other outside force, than a light one. Yet, of them- 

 selves, the one will stay up as long and gyrate as fast as 

 the other. 



This is another outcropping of the inertia-character 

 (if I may use so awkward an expression) of this instru- 

 ment. Two stones, however different in mass, will fall 

 equally fast, but if we attempt to slide them, even on a 

 Motionless plane, we will find a resistance proportionate 

 to the masses. 



THE TRANSFER OF WEIGHT FROM CENTRE OF GRAVITY 

 TO THE POINT OF SUPPORT. 



I showed with the balances that, in some way, the 

 weight while the Gyroscope stood out horizontally (as 

 in fig. 1), was transferred from the centre of gravity to 

 the point of support. 



The explanation becomes very simple by examination 



113 



