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Y. KOGA & O. YAMAGATA. 



following method of cutting which may be performed with a pair of 

 shears. It consists in cutting three equilateral triangles as shown 

 in Figure 9. 



Fig, 9. 



Fig, 10. 



The centre of gravity of the triangles should be upon the cir- 

 cumference of the inner circle whose diameter is equal to £■ of that 

 of the coin. 



In order to facilitate the cutting of such triangles of equal weight, 

 it is advisable to use a pattern of tin plate cut as shown in Figure 10. 



