SdS^^fZ. 



Ifhl 



A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE, 



OPTICAL PROJECTION. 



EXPERIMENTS 



ON 



LIGHT. 



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ILLUSTRATED 



CATALOGUE, 

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Set of Three Prisms, mounted as above, with Screens to show 



Principles of Achromatic Lens and Direct Vision Spectroscope 



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NEWTON & CO., 3, FLEET STREET, LONDON. 



A NEW GAS FURNACE 



(Holloway's Patent) 



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K I, A l)\' N !•: X T VV)'', I'', K. 



VOLCANOES. 



I'.V 



T. G. BONNEY, D.Sc, LL.D., F.R.S., 



Professor of (loiiloi^y :U University Colluf;c, London. 

 Large Svo, cloth extra, fully Illustr.ited, 6s. 



The last Vol. published was RIVER DEVELOP- 

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JOHN ^^•KkA^•, albkmakle strki;t. 



SPECTACLES 

 ELECTRIC LIGHT, INCANDESCENT GAS, 



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