NA TURE 



[May 1 8, 1905 



LIQUID AIR AND LIQUID HYDROGEN. 



Dr. HAMPSON'S AIR-LIQUEFIER is now made to a standard pat- 

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 very easily moved ; the Liquefier, without stand, being a cylinder 17 inches 

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It begins to liquefy air in from 6 to 10 minutes after the admission of air 

 at from 150 to 200 atmospheres pressure, making over a litre of liquid per 



miliary refrigerant and produ 



. perfectly clear liquid 



It requires r 



which requires no hltering. 



The operator has only one gauge to watch and one valve to control 

 HYDROGEN LIQUEFIER to the designs of Dr. MORRIS W. 



TRAVERS for use in conjunction with Air-Liquefier. 



For Prices and Particulars apply to the Sole Makers :— 



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ELVERTON STREET, WESTMINSTER. S.W. 



CALCIUM METAL 

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at X'7/O per pound bar, or 4 oz. &I- 



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PHOENIX 



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FIRE OFFICE. 



19 LOMBARD ST., E.G., and 57 CHARING CROSS, S.W. 



Established 1782. 



Moderate Rates. AbBOlute Security. Blectrlc 



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LOSSES PAID OVER £ae,000,0'>0. 



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ESTABLISHED 1851. 



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12 12/ 



MACMILLAN & CO.'S NEW BOOKS. 



TWENTY-SIX GRADUATED EXERCISES IN GRAPHIC STATICS, 



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By 



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THE PRINCIPLES OF ECONOMICS. 



A Fragment of a Treatise on the Industrial Mechanism of Society, 



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A MANUAL OF QUATERNIONS. g 



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THE TRADE POLICY OF GREAT BRITAIN AND HER COLONIES SINCE 1860. 



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PROBLEMS OF THE PANAMA CANAL, including Climatology of the Isthmus, 



Physics and Hydraulics of the River Chagres, cut at the Continental Divide, and Discussion of Plans for the Waterway. 

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THE BAHAMA ISLANDS. Edited by George Burb.ank Shattuck, Ph.D., 



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