384 



SCIENTIFIC NKWS. 



[April 20, iS 



tricians, at 8 p.m. — On the Risks of Fire, 

 Incidental to Electric Lighting ; by Mr. 

 W. H. Preece. 



Camera Club, at 8 p.m. — Platinotype Print- 

 ing ; by Mr. Willis. 

 Friday, April 27. — Royal United Service Institute, at 3 p.m.^ 

 The Mechanism of the Counter Attack ; by 

 MajorWalterW. M. Smith, R.A. 



Royal Institution, at 9 p.m. — Electrical In- 

 fluence Machines ; by Mr. J. Wimshurst. 



Parkes Museum, at 8 p.m. — Scavenging, 

 Disposal of Refuse and Setvage ; by Mr. H. 

 Percy Boulnois. 

 Saturday, April 28. — Royal Institution, at 3 p.m. — The Later 

 Works of Richard Wagner; by Mr. C. 

 Ambuster. 



Physical Society, at 3 p.m. — On Electto- 

 tnotive Force by Contact ; by Mr. C. V. 

 Burton. On a Theory Concerning the 

 Sudden Loss of Magnetic Properties of 

 Iron and Nickel ; by Mr. H. Tomlinson. 

 Note on the Graphic Treatment of the La- 

 mont Frolich Formula for Induced Magne- 

 tism, Note on the Conditions of Self- 

 excitement in a Dynamo Machine. Note 

 en the Conditions of selfregzdation in a 

 Constant Potcntional Dynamo Machine ; 

 by Professor S. P. Thompson. 



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Chisel Steel, l to 5 feet bars, f to l\ octagon, 13s. per cwt. — 

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Best Cast Steel for tools, taps, and dies, drills, 6d. per lb. — 

 ■Gilbert, Oxford Road, Sheffield. 



Rubber Stamps for business or private use ; excellence 

 guaranteed ; lists id. — A. H. Pashley, 12-14, Ecclesall Road, 

 Sheffield- 

 Electro - Plating and Gilding successfully taught. Every 

 requisite supplied. — Address, Henric, 234, Great Colmore-street, 

 Birmingham. 



Practical Hints on Electro-Plating, etc. — i stamp. — 

 Address, Henric, 234, Great Colmore-street, Birmingham. 



Dynamo, 120-candle power, improved armature, iocs. Photo. 

 5 stamps, — D. Walton, Hebden Bridge, Yorkshire. 



Dynamo, 60-candles, improved armature, 45s. ; photo. 5 stamps. 

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 each — D. Walton, Hebden Bridge, Yorkshire. 



Patents. — Nine months' protection, 50s. ; patent completed from 

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Meerschaum and Briar Pipes Repaired, Mounted, or cased, 

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New Dark Room Electric Lamp, ruby, orange, white alter- 

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S. Bottone, Carshalton, supplies, post free, the following 

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Plating Dynamo, £2; gives six amperes, at two volts; boy 

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Fretwork, Carving, Turning, Woods, Tools, and all 

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Second-hand Lathes, and other tools, offered cheap ; on 

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 for list, to Britannia Works, Colchester. 



" Inventors' and Manufacturers' Patent and Trade Mark 

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 Birmingham. Four stamps. 



"Sheet Metal Worker's Instructor," Warn's; few copies, 

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Minerals, Fossils (Carboniferous, Lias), 12 specimens, 

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Models, Scientific Apparatus, Tools, or Machinery taken 

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SELECTED BOOKS. 



A Manual of the Mollusca. A Treatise on Recent and 

 Fossil Shells. By Dr. S. P. Woodward, A.L.S. 

 With Appendix by Ralph Tate, A.L.S., F.G.S. With 

 numerous Plates and 300 Woodcuts, Fourth edition. 

 London : Crosby Lockwood and Sons. Price 7s. 6d. 



Elementary Microscopical Manipulation. By T. C. White. 

 Illustrated. London: Roper and Crowley. Price 2s.6d. 



The Hessian Fly, Cecidomyia destructor, in Great Britain 

 in 1887 : being mainly Reports of British Observa- 

 tions, with Illustrations from Life, and some means 

 of Prevention and Remedy. By Eleanor A. Orme- 

 rod. London : Simpkin and Marshall. Price 6d. 



Precautions to be adopted in Introducing the Electric Light. 

 With Notes on the Prevention of Fire Risks. By 

 K. Hedges. London : E. and F. N. Spon. Price 3s. 6d. 



A Manual of Dissections of the Human Body, for the Use 

 of Students, and more Particularly for those Preparing 

 for the High Examination in Anatomy. By the late 

 R. E. Carrington, M.D., F.R.C.P. Second edition. 

 Revised and Enlarged by W. Arbuthnot Lane, M.S., 

 F.R.C.S. London: George Bell and Sons. Price 9s. 



Natural History Object Lessons : A Manual for Teachers. 

 By G. Ricks. London : Isbister and Co. Price 4s. 6d. 



Electric Light Arithmetic. By R. E. Day, M.A., Evening 

 Lecturer in Experimental Physics at King's College. 

 London : Macmillan and Co. Price 2S. 



Geometrical Drawing. For the Use of Candidates for 

 Army Examinations, and as an Introduction to 

 Mechanical Drawing. By W. N. Wilson, M.A., 

 Assistant Master at Rugby School. London: 

 Rivington and Co. Price 4s. 6d. 



The Geological History of Plants. By Sir J. William 

 Dawson, C.M.G., LL.D., F.R.S. With 80 Figures 

 in Text. International Scientific Series. London : 

 Kegan Paul, Trench and Co. Price 5s. 



Tea Cultivation and Manufacture. By E. Money. Fourth 

 edition. Whittineham. Price los. 6d. 



NOTICES. 



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