Sept. 25, 1879] 



NATURE 



clxxvii 



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NATURE 



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Office : 29, Bedford Street, Strand. 



Now ready, a Revised Edition. 



NEGRETTI & ZAMBRA'S 



ENCYCLOP^lDIC 



Illustrated and Descriptive 

 CATALOGUE OF 



SCIENTIFIC INSTRUMENTS. 



(Containing very numerous Comparative Tables of Reference and 



l:luslrated by upwards of TWELVE HUNDRED ENGRAVINGS, 



Six Hundred Pages, Royal 8vo, cloth, gilt lettered, Price 5*. &/.) 



Oftical, Mathematical, Philosophical, Photographic, 



AND 



STANDARD METEOROLOGICAL 

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MANUFACTURED AND SOLD BY 



NEGRETTI AND ZAMBRA, 



opticians and Scientific Instntment Makers to 



The Royal Observatory, Greenwich; theAdmiralty ; Hon. Boardof Ordnance; 



Board of Trade; the British Meteorological Society; the Observatories 



Kew, Toronto, Washington, Victoria ; East Indian Government. 



HOLBORN VIADUCT, E.C, 



ALSO AT 



45, CORNHILL, E.G., & 122, REGENT STREET, W., 

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ELECTRICAL and SCIENTIFIC APPA- 

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 Liberal Terms to Schools and Science Teachers. Apparatus 

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~ DIAMONDS IN MATRIX. 



R. C. NOCKOLD, Diamond and Oriental Stone Cutter and Dealer, has 

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NOW READY, 

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G R I F F I N'S 



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A CATALOGUE OF CHEMICAL APPARATUS; 



ILLUSTRATED, CLASSIFIED, DESCRIPTIVE. 



Demy 8vo, 480 pp.. Illustrated with 1,600 Woodcuts. 



Most Complete and Cheapest List of Apparatus, 



JOHN J. GRIFFIN and SON.S, 22, GARRICK STREET, 

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BARCLAY & SON, 



138, REGENT STREET, LONDON. 

 la Her Majesty and H.R.H. the Prince of Wales. 



DUPLEX LAMPS. 

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READING LAMPS. 



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^ C. TiSLEY C& Co. 



OPTICIANS, '' 

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(Close to South Kensington Museum). 



THE PHONEIDOSCOPE 



An Instrument for Observing the Colour-Figures of Liquid Films under the 



action of Sonorous Vibrations. 



Being a visible demonstration of the Vibratory and Molecular Motion of a 

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The PHONEIDOSCOPE, with 3 Discs. Bottle of Solution, Descriptive 

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MANUFACTURED AND SOLD WHOLKSALH AND RETAIL BY 



S. C. TISLEY & CO., 172, BROMPTON ROAD, LONDON, S.W. 



TELEPHONIC ELECTRICITY. All Materials supplied for experi- 



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 Price Lists of Electrical and Acoustic Apparatus, with Drawings and 

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LIGHTNING CONDUCTORS. 



Experience, accumulated since th« time of Benjamin Franklin, proves 

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 destructive effects of Ughtnii^. 



NEWALL & CO.'S 



PATENT COPPER LIGHTNING CONDUCTOR, 



As applied to all kinds of Buildings and Shipping; in all parts of the world 

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It is stmple in its application, no insulators beingrequired, and it costs 

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36, WATERLOO ROAD, LIVERPOOL 

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EAGLE INsIjRANCE COMPANY, 



79, PALL MALL. 

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GEORGE HUMPHREYS, Actuary and Secretary. 



