C7UC>'V 



A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ground 

 Of Nature trusts the mind which builds for aye." — Wordsworth. 



No.. I $47, Vol. 64] 



THURSDAY, MAY 23, 1901. 



[Price Sixpence. 



l^'-glsteredas a Newspaper at the General Post Office.] 



[All Rights are Reserved. 



WIRELESS 



TELEGRAPHY. 



The Admiralty have adopted the "APPS- 

 NEVVTON' INDUCTION COILS as the 

 standard pattern for "Wireless Telegraph y 

 in the British Navy, and a large number 

 are now being constructed for use on 

 H.M. Ships at the London Worlvshops of 



NElftTTON & CO., 



3 FLEET STREET, LONDON. 



DEMONSTRATION BALANCE 



PHYSICAL 

 EXPERIMENTS. 



Specially designed to show 

 the principles underlying the 

 construction of the Balance. 



£9:0:0. 



FCLL I'ARTICULARS 

 ON APPLICATION. 



JOHN J. GRIFFIN (fc SONS, Ltd, 



20-26 SARDINIA ST., LINCOLN'S INN, W.C. 



A NEW 

 LENS 



^^\HHEIL Ofi^ 



FOR ALL 



WORK. 



In 3Se 

 I. GENER.^L. 

 II. CONVKRTIBLE. 

 III. SEECIAL PROCESS. 





This rapid, wide, medium or narrow angle lens all in one is 



suitable for all work. 



Fufl Catalo^ut' free on application re the Manufacturers :~ 



R. «& a. beck:, Ltd., 



68 CORNHILL, LONDON, E.C. 



NEGRETTI 



ZAMBRA'S 



IMPROVED 



SELF-RECORDING RAIN- 



CAUGfS, BAROMETERS & 



THERMOMETERS, 



Giving continuous Records 



on Cliarts which only require 



changing weekly. 



Invaluable to Invalids and 

 others unable to take^daily 

 readings.' " 



Illustrated Price List of Instruments free-.by Postrto-all 

 parts of the World 



NEGRETTI & ZAMBRA, 

 38 HOLBORN VIADUCT, E.G. 



Branches: 4; CORNH II.L. .itul 122 REGENT STREEH. 

 AWARDED T^O GOLD MEDALS PARIS EXHIBpTION 1900 



