J 



A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ground 

 in Wature trusts the mind which builds for aye." — Wordsworth. 



No. 257 ■ VoL - '° 2 ] 



THURSDAY, JAN L'ARY 301919 



[Price Ninepence. 



rl n< .1 Newspaper at tl Post Office.) 



[All Rights Reserved 



OPTICAL PROJECTION APPARATUS 



or 



EVERY DESCRIPTION. 



# 



LOW POWER PROJECTION MICROSCOPE 



for attaching to any Optical Lantern. 



NEWTON & CO. 



(late of 3 Fleet Si> 1 

 72 WIGMORE STREET, LONDON, W. 1. 



DUROGLASS L™ 



14 CROSS STREET, HATTON GARDEN, E.C. 



Manufacturers of 



Borosilicate Resistance Glassware. 



Beakers. Flasks, Etc. 



Soft Soda Tubing for Lamp Work. 



General Chemical and 



Scientific Glassware. 



Special Glass jjpparatus Made to Order. 



DUROGLASS WORKS, WALTHAMSTOW. 



AGENTS : 



BAIRD & TATLOCK (LONDON) LTD. 

 14 CROSS ST., HATTON GARDEN, E.C. 1. 



REYNOLDS & BRANSON, Ltd. 



Chemical and Physical Apparatus Makers to His Majesty's 



Government (Home and Overseas Dominions). 



Laboratory Outfitters, &c. 



Cold Medals at Allahabad I 



and Cold Medal 



APPARATUS for MACKENZIE 

 and FORSTERS THEORETICAL 

 and PRACTICAL MECHANICS and 

 PHYSICS as adopted by H.M. 

 Government and many important 

 Educational Authorities. Price Lists 

 on application. 



Vide : — " Theoretical and 

 Praciical Mechanics and 

 Physics," by A. H. Mac- 

 kenzie, M.A., B.Sc, and 

 A. Forster, B.Sc. 

 Price - - Post Free 1/9. 



CATALOGUES POST FREE. 



Optical Lanterns and Lantern Slides ; Chemical and Physical Apparatus 



and Chemicals; British Made Laboratory War* (Glass, Porcelain, Niclcei. 



and Filter Papers); Chemicals of Guaranteed Purity. 



14 Commercial Street, Leeds. 



BECKMANN THERMOMETERS 



With 6 degrees Centigrade divided 

 into 001° C, are now made 

 throughout at our own works. 



NEGRETTI & ZAMBRA 



38 HOLBORN VIADUCT, E.C. 1 

 5 LEADENHALL ST., E.C. 3 

 122 REGENT STREET, W. 1 



LONDON. 



