Oct. 23, 1879] 



NATURE 



CCIX 



SUBSCRIPTIONS TO NATURE 



Yearly 28J. 



Half-yearly 14J. 6</. 



Quarterly "js. 6d. 



To the Colonies, United States, the Continent, and 

 all places within the Postal Union ; — 



Yearly 3&f. 6d. 



Half-yearly 15s. 6d. 



Quarterly 8^. 



Oflfice : 29, Bedford Street, Strand. 



Now ready, a Revised Edition. 



NEGRETTI & ZAMBRA'S 



ENCYCLOP^IDIC 



Illustrated and Descriptive 

 CATALOGUE OF 



SCIENTIFIC INSTRUMENTS. 



(Containing very numerous Comparative Tables of Reference and 



Illustrated by upward* of TWELVE HUNDRED ENGRAVINGS. 



Six Hundred Pages, Royal 8vo, cloth, gilt lettered. Price 5J. 6d.) 



Ojtical, Mathematical, Philosophical, Photographic, 



AND 



STANDARD METEOROLOGICAL 

 INSTRUMENTS. 



MANUFACTDIillD AND SOLS BY 



NEGRETTI AND ZAMBRA, 



opticians and Scientific Instrument Makers to 



TheRoyalObscrvatory,Greenwich; tbeAdmiralty; Hon. Board of Ordnance 



Board of Trade: the British Meteorological Society: the Observatories 



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



HOLBORN VIADUCT, E.G. 



Also AT 



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

 LONDON. 



M. JACKSON & CO., 



(J. ORME and H. M. CAPNER) 

 MANUFACTURERS AND IMPORTERS OF 



SCIENTIFIC APPARATUS 



AND 



: CHEMICALS, 



Sole Agents for Hickley's Patent Telephones, 



Price ips. per Pair, Cash with Order. 



Price Lists sent on receipt of Three Stamps for Postage. 



For Trade Terms inclose Business Card. 



65, BARBICAN, LONDON, E.G. 



CHEMICAL & PHYSICAL APPARATUS 



BOTTLES, PURE CHEMICALS, 



And every requLremcDt for Science Classes, Private Study, or Buiineu 



Purposes 



Illustrated Priced Catalogues post free for six stamps. 



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



value and upwards. 



MOTTERSHEAD AND CO. 



7, EXCHANGE STREET, & 10, HALF MOON STREET, 

 MANCHESTER. 



EUDOLPH KOENIG, 



(DR. PHIL.) 

 MANUFACTURER OF 



ACOUSTICAL INSTRUMENTS. 



TO ILLUSTRATE THE LAWS 



AND TO PRODUCE THE PHENOMENA OF SOUND. 



PARIS, 26, RUE DE FONTOISE. 



PRICE LISTS FREE. 



EAGLE INSURANCE COMPANY, 



79, PALL MALL. 

 FoK Lives only. Establishsd 1807. 

 Net Premiums and Interest .»...._......•> ;C39S>8iB 



Accumulated Funds .»m.».....«m«m«m. ;C3,o33,38x 



Also a Subscribed Capital 06 more than ... m. .« .« .^1,500,000 

 Reports, Prospectuses, and Forms may be had at the Office, or from any 

 of the Company s Agents, post free. 



GEORGE HUMPHREYS, Actuary and Secretary. 



THE SCIOPTICQN. 



CATALOGUES FREE. 



THE SCIOPTICON COMPANY, 



157. 

 GREAT 



PORTLAND 



STREET, 



LONDON, W. 



LIGHTNING CONDUCTORS, 



Experience, accumulated since the time of Benjamin Franklin, proves 

 conclusively that a Conductor made of Copper of adequate size is the best 

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

 destructive effects of lightning. 



NEWALL & CO.'S 



PATENT COPPER LIGHTNING CONDUCTOR, 



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

 with unvarying success, is the most Reliable, most Effective, and Cheapest 

 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 site, wliich is safe in any stonn. 



B. S. NEWALL & CO., 130, STRAND, W.C. 



' ^, WATERLOO ROAD, LIVERPOOL. 

 68, ANDERSTON QUAY, GLASGOW. 

 MANUFA0TORY -GAT£SHEAD*ON-TYNE. 



W. F. STANLEY, 



Mathematical Instrument Manufacturer 



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

 Department, Admiralty, &c. 



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

 the highest iiuality and finish, at the most moderate prices. 



Price List post free. Engine Divider to the Trade. 

 ADDRESS- 

 GREAT TURNSTILE, HOLBORN, LONDON, W.C, 



THE "HANSA," 



Published rinca i8«4, in Hamburg, is the only independent professional 

 paper in Germany, dedicated exclusively to Maritime Objects. Essays, 

 Critiques, Reviews, Reports, Advertisements. Strict eye kept upon the deve- 

 lopment of Maritime Affairs in every respect. Every second Sunday one 

 Number in 4to at least ; frequent supplements and drawings. Subscription 

 at any time ; preceding numbers of the year furnished subsequently. Pnc* 

 IM. for twelve months. Advertisements td. a line, widely spread by this 

 paper; considerable abatement for 3, 6, 12 months' insertion. Business 

 Oflice : Aug. Meyer and Dieckmann, Hamburg, Altcrwall, 38. Edited by 

 W. V. Fksbdeh, M.R., Hamburg, Alexander Street, 3. 



