July 24, 1879] 



NATURE 



ci 



SUBSCRIPTIONS TO NATURE 



Yearly 28J. 



Half-yearly 14J. 6rf. 



Quarterly Ts. td. 



To the Colonies, United States, the Continent, and 

 all places -within the Postal Union : — 



Yearly 3<^- ^• 



Half-yearly i<,s. (td. 



Quarterly 8j. 



Office : 29, Bedford Street, Strand. 



L'ELEGTRIGITE 



Rovtio scientlflLcjuo illustreo 



Paraissant le 5 et lu 20 do chatjue mois 

 Eii unebelU- Uvraisoa de vingt-quatre pages grand inSo J^aui 



Telegrapliie. — Galvanoplastie. — Meteorologie. — Medeciao 

 Art inilitaire. — Applications diverses 



ORGANE SPKCIAL DK3 PR0GKK3 DB LA LUMlfCUE ELECTIUQUB 



Publication redigeo depuis I87(i avec la collaboration de» 

 priucipaux electriciens fran^ais et etrangers. 



Secretaires do la U'WIaction : \V. de FoNviBi.LEet le Gt«D'ARRO&. 

 Directeur : E. pe Clisson. 



CONDITIONS D'ADOXNEMENT : 



•2 *|||U!nM DDCTRI TM &Q< •• I* » 



6 mois. 7 50 

 15 > 

 8 • 



Prix d*uno livraison : n 76 



PARISETDEPARTEHENTSJjjJ^v; 'J ^JjUMON POSTALE 



ETATS-UNIS O'AMtRIQUE.;! ^y 

 " lb moi3. 



Fa numiro tficimen est envoys gratis sur loute demand* affranchU 



adrcsS('e au bureau ilu Jvurnat : 



Paris. 16, rue du Croissant, Paris. 



W. L A D D & CO., 



Scientific Instrument Manafactnrers 



(.Sf AppotHtment to tht Royal Imtitution of Gnat 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, «c, 



LADD'S IMPROVED SELF-CHARGING HOLTZ 

 ELECTRICAL MACHINE, with 4 to 12 Plates, in- 

 closed in a Mahogany and Glass Case. This instrument is 

 immediately available in any condition of the atmosphere. 

 Philosophical Apparatus of every Description. 



Illustratld Catalogut, Sixptrut. 



EAGLE INSURANCE COMPANY, 



79, PALL MALL. 

 Fos Lives only. Established 1807. 

 Net Premiums and Interest ... .« .« «. ..• •- ;C39fi>8i8 



Accumulated Funds ... «• ... .« «• m< ;£3,o83,38i 



Also a Subscribed Capital o£ more than ... .« >£i, 500,000 



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

 of tlie Company s Agents, post free. 



GEORGE HUMPHREYS, Actuary and Secretary. 



HORNE'S POMPEIAN DECORATIONS. 



ROBERT HORNE, 



HOUSE DECORATOR and PAPER-HANGING 



MANUFACTURER, 



41, GRACECHURCH STREET, LONDON, E.C. 



By Special Appointment to His Majesty the King of Italy. 



JOHN NORMAN, 



manufacturer of 



MICROSCOPES, OBJECTS, CABINETS, 



TABLES, LAMPS, 



And all Class Appliances for Microscopes, 



HA.S OPENED NEW AND EXTENSIVE PREMISES AT 



34, Whitecross Street, Cripplegate, E.G. 



List* post free on application. 



LIGHTNING CONDUCTORS, 



Kxperience, accumulated since the time of Benjamin Franklin, prore* 

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

 of all appliances for the protection o£ every description o£ buUdin£ from the 

 destructive effects of lightnins. 



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 sise, which is safe in any storm. 

 a. S. NEW^ALZi A CO., 130, STRAND, W.C. 



36, WATERLOO ROAD, LIVERPOOl.. 

 68. ANDERSTON QUAY, GLASGOW. 

 MANUFACTORY— GATESHE AD-ON-TYNK 



Now ready, a Revised Edition. 



NEGRETTI <& ZAMBRA'S 



encyclop.s;dic 

 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 Uttered, Price 5^. 6tf.) 



Optical, Mathematical, Philosophical, Photographic, 



AND 



STANDARD METEOROLOGICAL 

 INSTRUMENTS. 



MANUFACTUKED AND SOLD BY 



NEGRETTI AND ZAMBRA, 



Opticians and Scientific Instrument Makers to 



The Royal Observatory, Greenwich; the Admiralty ; 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. 



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. 



NOW READY, 

 SECOND EDITION, 



GRIFFIN'S 



CHEMICAL HANDICRAFT. 



PRICE V. id. POST FREE. 



A CATALOGUE OF CHEMICAL APPARATUS; 



ILLUSTRATED, CLASSIFIED, DESCRIPTIVE. 



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



Mtst Complete and Cheapest List of Apparatus. 



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

 LONDON, W.C. 



