A WEEKLY ILLL'bi RATED JOURNAL OF SCIENCE. 



' ' To the solid grotmd 

 Of Nature trusts the mind which builds for aye." — Wordsworth. 



THE BEATING OF THE HEART 

 THE MOVEMENTS OF THE DIAPHRAGM 



Can be seen by the aid of the Special "Focus" Tubes (255^. 



each) and the Fluorescent Screens (35^^. each) made by 



NEWTOX & CO., 3 Fleet Street, London, if used with 



one of their 6-inch Induction Coils. 



N E WTON & CO., 3 FLEET STREET, LONDON, 

 Are now prepared to supply the well-known " Focus " Tubes 

 manufactured by them at the reduced price of 25S. each. 

 These Tubes are still unsurpassed for Rapidity, Brilliancy 

 and Definition. 



■ When ordering, the length of Spark to be used, should be 

 mentioned. 



.Ml the Tubes for 6" Spark and upwards will work right 

 through the human body, showing the heart, liver, spine, ribs, 

 movements of the heart, diaphragm, &c. 



Cu.stomers can see these Tubes at work at 3 Fleet Street, 



Li IN I, ON. 



NEW FLUORESCENT SCREENS, extremely brilliant, 

 8' X 5", 35s. each ; 10 < 8', 63s. each. 



BECK'S MICROSCOPES. 



No. 2SA.— THIS MODEL, with 

 l-in. and i-in. Object Glasses, 

 Two Eyepieces, and packed 

 in Polished Mahogany Case, 



£6 10s. 



No. 251!.— THIS MODEL, with 

 5-in. and }-in. Object Glasses, 

 Two Eyejiieces, and packed 

 in Polished Mahogany Case, 



£7 5s. 



STAND No. 25. 



No. 29B. — The addition of Abbe 

 Condenser to 25B with Iris 

 Diaphragm and Focussing 

 and Swinging AdjustmenU, 



£8 15s. 



iVI.I. PARTICULARS FREE on Al'l'l.ICATION to 



R. & J. BECK, Ltd., 68 cornhill, London, e.c. 



BROWNING'S "STRAND" 



HALF-PLATE 



PHOTOGRAPHIC OUTFIT. 



Comprising i-Plate Double Ex- 

 tension Mahogany body Camera, 

 with Rising and Falling Front, 

 Reversing Back and Leather Bel- 

 lows ; one Double Dark Slide ; 

 Rapid Rectilinear Lens, Iris Dia- 

 phragm ; Thornton-PickardShutter: 

 Tripoli Stand ; Focussing Cloth, 

 and Waterproof Case. 



Price complete, £4 18s. 6d. 



Illiislratcd Catalogue of Photo- 

 graphii Apparatus Post Free. 



JOHN BROm^NINO, 



Manufacturing Optician, 

 63 STRAND, LONDON, JW.C^ 



NEGRETTI & ZAMBRA, 



SOLE MAKERS OF 



JORDAN'S (PATENT) SUNSHINE RECORDER. 



New Simplified Model, 

 adjustable for any 

 latitude, and tho- 

 roughly efficient. 

 Price £1 7s. 6d. 



Sensitised Charts, 

 5s. per 100. 



NEGRETTI 

 ZAWIBRA, 



Scientific Instrument 

 Makers to the Queen, 



38 HOLBORN VIADUCT. 

 Branches — 45 Cornhill, 



iiilii. Lo.o"or-^-^ ^"^"• 



ILLUSTRATED DESCRIPTION POST FREE. 



Telephone No. 6=8 



Telegraphic Address, " Negrelli, London.' 



