clxvi 



NA TURE 



[August 24, 1905 



Ultra-Violet Rays 



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Current consumption only 2 to 3 amperes. 



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ueci by Richard Clay and Sons, Limited, at 7 c4: S Bread Street Hill, Queen Victoria Street, in the City of London, and published by MacmillaN 

 \ND Co., Limited, at St. ^L'^rIin'6 Street, London, W.C, and The Macmillan Company, 66 Fifth Avenue, New York. —Thursday, August 24, 1905. 



