NA TURE 



[October 12, 1905 





All other air 

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f» 



THE. 



"GERYK 



{Fleuss Patent) 



Vacuum Pump. 



R.esults hitherto only pos- 

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 are readily obtainable by 

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vacuum pump. 

 Price from Write for 



84 : 5 : 0. LIST F.45. 



puUometer engineering QSXi 

 t&ut eim* Ironworks. 12£ading. 



CHARLES GRIFFIN & CO., Ltd.'s, 

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JUST OUT. FULLY ILLUSTRATED. 6.<. net. 



TESTING EXPLOSIVES. 



CONTEl 



^on.busti 

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By C. E. BICHEL 



;ts.— Historlcal-Te.sling Stat! 

 in — Heat of Decomposition — R; 

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d AXEL LARSEN. 



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JUST OUT. VOL. L FIFTH EDITION. REVISED. Ss. 6d. 



APPLIED MECHANICS, 



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By ANDREW JAMIESON, M.Inst. C.E., M.I. E.E.,F.R.S.E. 



In T>vo Parts. Part I. -The Principle of Wrrk and its .Applica'ions. 

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SIXTH EDITION. REVISED. FULLY ILLUSTRATED. 31. bd. 



AN ELEMENTARY MANUAL OF 



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By ANDREW JAMIESON, M.Inst.C.E., M.I.E.E. 



" A thoroughly trustworthy text-book. Practical and clear." — Nature. 



PROPERTIES OF MATTER. 



Being Volume I. of A TEXT-BOOK OF PHYSICS. 

 By J. H. POYNTING, Sc.D., FR S., 



Professor of Physics, Birmingham University, and 



J. J. THOMSON, M.A., F.R.S., 



Fellow of Trinity College, Cambridge; Piofes.sor of Experimental Physics 



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" We regard this book as quite indispensable not merely to teachers, but 



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FORTIN'S 

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By the absence of the ordinary tubular enclosures (in the 

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The bore of the tube is 0-5 inch. 



The scales are graduated in inches and millimetres, and, 

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The attached Thermometer on the body of the instru- 

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