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THE ROYAL SOCIETY OF CANADA 



III. — Brass Rods were now tried. Breadth of Rods = 1.94 cms. 

 Fixed Glass Cylinder of diameter 2.51 cms. used. 



One quarter of 1 . 58 = . 40 nearly. 



The experiment is interesting inasmuch as it gives the student 

 an example of a vibrating body with a movable point of support. 

 Its likeness to a see-saw will give it familiarity, and he can now go 

 on to study the effect of loading up the ends and so improving the 

 likeness. 



Note added October, 1921, 



Just about two months ago the author saw an experiment similar to the above 

 in use in the classes of Dr. G. F. C. Searle at the Cavendish Laboratory, University 

 of Cambridge. Dr. Searle works on a larger scale using a rod about one metre long 

 and one centimetre thick resting on a vertical wheel of diameter about twenty 

 centimetres. The value of g is deduced from the readings. An account of this 

 experiment is given in Searle's "Experimental Harmonic Motion". The author 

 was not aware of Dr. Searle's work when he wrote the above paper. Using the 

 readings for the longer brass rod of the above table in Eq. 4. the value obtained for 

 g is 970 cms. per sec. per sec. 



