754 



THE POPULAR SCIEXCE MONTHLY 



Fig. 8. JP] ^ Q f 2^FW. 



V °f 



Fig. 9. P/an of 3& Floor 



io feet 



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Plan of «*** FlooS 



JO 



feet 



10 feet. 



Fig. 11. 



10 f 



FUr, of 5"> Floor. 



