Oct. 9, 1879] 



NATURE 



cxcni 



SUBSCRIPTIONS TO NATURE 



Yearly i%s. 



Half-yearly 14J. 6//. 



Quarterly "js. 6il. 



To the Colonies, United States, the Continent, and 

 all places within the Postal Union : — 



Yearly 30J. 6rf. 



Half-yearly i^s. 6d. 



Quarterly 8j. 



Office : 29, Bedford Street, Strand. 



rs'ow ready, a Revised Edition. 



NEGRETTI & ZAMBRA'S 



ENCYCLOPAEDIC 



Illustrated and Descriptive 

 CATALOGUE OF 



SCIENTIFIC INSTRUMENTS. 



(Containing very numerous Comparative Tables of Reference and 



Illustrated by upwards of TWELVE HUNDRED ENGRAVINGS. 



Six Hundred Pages, Royal 8vo, cloth, gilt lettered, Price $s. 6d.) 



Of tical. Mathematical, Philosophical, Photographic, 



AND 



STANDARD METEOROLOGICAL 

 INSTRUMENTS. 



MANUFACTURED AND SOLD BY 



NEGRETTI AND ZAMBRA, 



Opticians and Scientific Instrument Makers to 



The RoyalObscrvatory, Greenwich; the Admiralty; Hon. Board of Ordnance 



Board of Trade ; the British Meteorological Society; the Observatories 



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



HOLBORN VIADUCT, E.C, 



ALSO AT 



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

 LONDON. 



NOW 



A D y. 



SECON D E DITION, 



GRIFFIN'S 



CHEMICAL HANDICRAFT. 



PRICE 41. 7</. POST FREE. 



A CATALOGUE OF CHEMICAL APPARATUS: 



ILLUSTRATED, CLASSIFIED, DESCRIPTIVE. 



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



^ Alost Comphle and Cheapest List of Apparatus. 



JOHN J. GRIFFIN and SONS, 22, GARRICK STREET, 

 LONDON, W,C. 



DRAPER'S INK (DICHROIC). 



THE NEW BLACK INK 



DIFFERING FROM ANYTHING ELSE EVER PRODUCED. 

 Writing becomes a pleasure when this Ink is used. It has been adopted 

 by the principal B.-inks, Public OfTices, and Railway Companies tiu-ougnout 



Ireland. 

 It writes almost instantly Full Black. I Flows easily from the Pen. 

 iJoes not corrode Steel Pens. Blotting-paper may be applied at the 



Iscleanly to use, and not liable toBlot. i moment of writing. 



Can be obtained in London, through Messrs. Barclay & Sons, Farring- 

 don Street; W. Euwarus, Old Change; F. Newberv & Sons, Newgate 

 Street; Wm. Mather, London and Manchester; J. Austin & Co., Duke 

 Street, Liverpool ; and Stacy & Cook, Paternoster Row ; and to be had of 

 all Stationen. 



BEWLEY & DRAPER (Limited), Dublin. 



EUDOLPH KOENIG, 



(DR. PHIL.) 

 MANUFACTURER OF 



ACOUSTICAL INSTRUMENTS. 



TO ILLUSTRATE THE LAWS 



AND TO PRODUCE THE PHENOMENA OF SOUND. 



PARIS. 26, RUE DE POHTOISE. 



PRICE LISTS FREE. 



THE SCIOPTICON. 



CATALOG UES FREE. 



THE SCIOPTICON COMPANY, 



157. 

 GREAT 



PORTLAND 



STREET, 



LONDON, W. 



W. F. STANLEY, 



Mathematical Instrument Manufacturer 



To H.M.'s Government, Council of India, Science and Art 

 Department, Admiralty, &c. 



Mathematical, Drawing, ,ind Surveying Instruments of every description, of 

 the highest quality and finish, ct the most moderate prices. 



Price List post free. Engine Divider to the Trade. 

 ADDRESS- 

 GREAT TURNSTILE, HOLBORN, LONDON, W.C. 



CHEMICAL & PHYSICAL APPARATUS 



BOTTLES, PURE CHEMICALS, 



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



Purposes 



Illustrated Priced Catalogues post free for six stamps. 



Carriage allowed to any station in England or Wales, on orders of 40*. 



value and upwards. 



MOTTERSHEAD AND CO. 



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

 MANCHESTER. 



LABORATORY, 38, GRACECHURCH STREET, LONDON, EC. 



A. ANTHONY NESBIT, F.C.S., 



WATER ANALYST, 



Performs every description of Water Analysis on moderate terms. 



Properly cleansed bottles for the reception of samples sent to any piut of 



the Kiagdom. 



LIGHTNING CONDUCTORS. 



Experience, accumulated since the time of Benjamin Franklin, proves 

 conclusively that a Conductor made of Copper of adequate size is the bi-st 

 of all appliances for the protection of every description of building from the 

 destructive effects of lightning. 



NEWALL"*" CO.'S 

 PATENT COPPER LIGHTNING GONDUGTOP.. 



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

 with unvarying success, is the most Reliable, mcst Kficctivc, and Che.ipest 

 Conductor ever offered to the public. . . 



It is simple in its application, no insulators being required, and it costs 

 only one shilling per foot for the standard size, which is safe in any storm. 

 E. S, NEW ALL & CO,, 130, STRAND, W.C. 

 «,. D, fljiwaiii. «. v«,, ^ WATERLOO ROAD, LIVERPOOL. 



63, ANDKRSTON QUAY, GLASGOW. 

 MANUFACTORY-GATESHEAD-ON-TYNK. 



