August 14, 1879] 



NA TURE 



cxxvn 



NOTICE OF REMOVAL. 



JAMES HOW & CO., 



SCIENTIFIC INSTRUMENT MAKERS, 

 73, FAREINGDON ST., LONDON 



(Late or 5, St. Bride St., and 2, Foster Lane). 



HOWS STUDENT'S MICROSCOPE. HOW'S MICROSCOPE LAMP. 



Rock Sections and other Objects for the Microscope. 



The LANCASTER POCKET CAMERA 



for plates 4J X 3J inch, havinc; three double dry.plate Slide*, Umbrella 

 Stand, best Lems with plate tf Diaphragms, &c., &c., £s- i*articular« 

 free. 



The LANCASTER CARTE PHOTOGRA- 

 PHIC APPARATUS, with Chemicals, &c., &c., complete, /s jf- 

 FIRST QUALITY ASTRONOMICAL TELESCOPES with Object 

 Lenses, by Wkay, 2}-inch, £,^ os. ; aj-inch, £7 lor. : 2f-inch, £i*; 

 3-iBch, £it lot.; si-inch, ;£i5i5J.; 4-inch, £is; 4}-i«ch, £^%; 

 5-inch, £ss, &c. Capital Student's Microscope, £-3 31. Collegian's 

 First Quality Microscope, £^ ^s. lllustratti Catalogue, 3 Stamps. 

 J. LANCASTER it SON, Opticians, BirminEham. 



BARCLAY & SON, 



IS8, REGENT STREET, LONDON. 

 7o Her Majesty and H.R.H. the Prince of Wales. 



DUPLEX LAMPS. 

 MODERATOR LAMPS. 



READING LAMPS. 



MICROSCOPE LAMPS. 



BEST COLZA OIL. 



A I KEROSINE OIL. 



WAX, SPERM, 



\ 



PARAFFINE CANDLES. 



ILLUSTRATED CATALOGUES POST FREl. 



CHEMICAL & PHYSICAL APPARATUS 



BOTTLES, PURE CHEMICALS, 



And every requirement for Science Classes, Private Study, or Business 



Purposes, 



Illustrated Priced Catalogues post free f«r six stamps. 



Carriage allowed to any station in England or Wales, on orders of 4W. 

 value and upwards. 



MOTTEESHEAD AND CO. 



7, EXCHANGE STREET, & lo, HALF MOON STREET, 

 MANCHESTER. 



DIAMONDS IN MATRIX. 



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

 for sale specimens of the above ; also Cut Precious Stones in ilU Colturs. 



la, FRITH STREET. SOHO. W. 



NEW ILLUSTRATED CATALOGUE of ELECTRIC 



SIGNALS, &c., with Instructions for Fixing. 150 Diagrams. Just out, 

 post free, 6 Stamps. 



EDNA/ARD PATERSON, 



Electrical Engineer and Scitntific Apparatus Manufacturer, 



3, BEDFORD COURT, COVENT GARDEN, LONDON 



STEAM WORKS, GRAY'S INN ROAD. 



Experiments in Electric Lighting carried out. 



Eleciricml Apparatus of all Descriptions for Lecture Purposes Loaned out, 



APPARATUS for CLASS DEMONSTRATION and for SCIENCE 



SCHOOLS. 

 ELECTRIC LIGHT APPARATUS. 

 SIEMEN'S and GRAMME'S DYNAMO MACHINES and LAMPS 



for Hire and Purchase. 

 LARGE ASSORTMENT of RUHMKORFF COILS and VACUUM 



TUBES. 

 PROFESSOR HUGHES' MICROPHONE. 

 ELECTRIC BELLS and INDICATORS. 

 TELEPHONES and TELEPHONE CALL BELLS, WIRE, &c., for 



Fixing. 

 EDISON'S ELECTRIC PEN £% %s. 



ELECTRIC and MAGNETIC APPARATUS of all Descriptions. 

 Illustrated Catalogue tleclrical Apparatus, Part i. Post free, 6 Stamps, 

 ■lo do Electric Signals, Part 2. Post free, 6 Stamps. 



„ C. TISLEY & Co 



OPTIC I ANS, ■' 



172, BROMPTON ROAD, S.W. 



(Close to South Kensington Mus«um). 



THE PHONEIDOSCOPE 



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

 action of Sonorous Vibrations. 



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

 Telephone Plate. 

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

 Pamphlet, &c., in Cardboard Box, lof. (>d, 



MANUFACTURED AND SOLD WHOLESALE AND RETAIL BY 



S. C. TISLEV A CO., 172, BROMPTON ROAD, LONDON, S.W. 



TELEPHONIC ELECTRICITY. All Materials supplied for experi- 

 mental purposes. 



Prict Lists 0/ Electrical and Acaustzc Apparatus, with Drmwrngs and 

 Description of the H armtne^ra^h^ Post Free, ad. 



EUDOLPH KOENIG, 



(DR. PHIL.) 

 MANUFACTURER OF 



ACOUSTICAL INSTRUMENTS. 



TO ILLUSTRATE THE LAWS 



AND TO PRODUCE THE PHENOMENA OF SOUND. 



PARIS, 26, RUE DE PONTOISE. 



PRICE LISTS FREE. 



W. L A D D & CO., 



Scientific Instrnment Manufacturers 



(By appointment lo the Royal Institution of Great Britain), 



II & 12, BEAK STREET, REGENT STREET, W. 



BYRNE'S PATENT COMPOUND PLATE PNEU- 

 MATIC BATTERY for Cautery and general purposes. 



EDMUNDS' PHONOSCOPE for making Vocal Vibra- 

 tions visible in a Vacuum Tube, 



HUGHES' MICROPHONE. 



TELEPHONIC APPARATUS, ftc. 



LADD'S IMPROVED SELF CHARQINQ HOLTZ 

 ELECTRICAL MACHINE, with 4 to 12 PUtes, in- 

 closed in a Mahogany and Glass Case. This instrument is 

 immediately available in any condition of the atmosphere. 

 Philosophical Apparatus of every Description. 



Illustrated Catalogue, Sixpence, 



