

A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To /he solid ground 

 Of Suture frnits the mind which builds for aye." — Wordsworth. 



OPTICAL LANTERNS 



for 



Educational. Welfare. Scientific, and other 

 WORK of NATIONAL IMPORTANCE 



REYNOLDS & BRANSON, Ltd. 



Chemical and Physical Apparatus Makers to His Majesty's 

 Government (Home and Overseas Dominions), 

 Is I f ICriS. Laboratory Outfitters, &c. 



Gold Medals at Allahabad and London. Grand Prix and Gold Medal 

 at the International Exhibition. Turin. 



KTEViTTOlM Hi, CO., 



Makers of Optical Projection Apparatus of every descriptio 



(KsTAULlsllfU, OVF.R c 



72 WIGMORE STREET, LONDON, W. 1. 



<l 





s*V 



APPARATUS for MACKENZIE 

 and FORSTER'8 THEORETICAL 

 and PRACTICAL MECHANICS and 

 PHYSICS as adopted by H.M. 

 Government and many important 

 Educational Authorities. Price Lists 

 on application. 



Vide : — " Theoretical and 

 Practical Mechanics and 

 Physics," by A. H. Mac- 

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

 A. Forster, B.Sc. 

 T'tice - ■ Post Free 1/9. 



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 Jlpparalus Made to Order. 



DUROGLASS WORKS, WALTHAMSTOW. 



AGENTS : 



BAIRD & TATLOCK (LONDON) LTD. 



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



OGUSS POST FREE. 



Optical Lanterns and Lantern Slides ! Chemical and Physical Apparatus and 



Chemicals; British Made Laboratory Ware (Glass, Porcelain. Nickel 



Ware, and Filter Papers) ; Chemicals of Guaranteed Purity. 



14 Commercial Street, Leeds. 



CLINICAL THERMOMETERS 



Tested under the Govern- 

 ment Order of Oct. 11, 1918, 

 and bearing the mark of the 

 National Physical Laboratory 



NEGRETTI & ZAMBRA 



38 HOLBORN VIADUCT, E.C. 1 

 5 LEADENHALL ST., E.C. 3 

 122 REGENT STREET, W. 1 



LONDON. 



