A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



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John J. GRIFFIN &S»5 



MAKERS OF 



Physical Apparatus 



THE GRAY-BURNSIDE 



MOTOR GYROSTAT 



for deinoiisirating .ill ihe properties ami 

 practical applications of the gyrostat. 



GYROST ATIC PEN DULUM 

 GRAY'S GYROSTATIC MODELS 



As demonstrated at the Physical Society. 

 PRICKS 0\ AVI'I^ICATIOX. 



Kemble St. 



KINGSWAY 



London, W.C. 



ItBY NOIliDS St, :BFSAI>IS0I*, X^t.€L. 



••RYSTOS" MICROSCOPE 

 PLATFORM 



Gold Medals :- 

 London. 1908. 



Allahabad. 1911. 

 Grand Prix, Turin. 1911. 

 2 Medals, York, 1912. 



B 1 191S 



For use with the Stpoud & Rendell Science Lanterns. This platform 

 is adjustable, so that any ordinary micrcicope (the draw tube being 

 removed) can be used for projection work. The platform can be raised 

 or lowered in order that the optical centre of the microscope may 



coincide with that of the lantern ... _ ... £17 6 



Microscope as figured, with eyepiece and i"and ^"objectives... 7 5 



\" objective for projection purposes 10 



'Catalogiic of Optical Lanterns and descriptive circular of Accessory 

 Apparatus for the S. &^ J^ . Lanterns, post f7-cc. 



14 coivi]ViE:EeciA.iL< s':rEtE:E:'X<, i:^e:e:i>s. 



s- NEGRETTl & ZAMBRA'S 

 I RAIN GAUGES. 



•o The " Hyetograph," 

 ■'a Recording Rain 

 '•Gauge that is 

 So approved by the 

 S« highest authorities. 



So Price, complete, with 



•o charts, pen, and ink 



y £6 15 



%% Illuttralcd Price List of 

 •o Rain Gauges, etc., icnl 

 •o post free on requeil. 



o§ 38 Holborn Viaduct, 

 •* London, E.G. 



•J 45 Cornhill, EC. ;] 

 SS 122 Resent St., W. 



