A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE 



" To the solid ground 

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



No. 495, Vol. 19] 



THURSDAY, APRIL 24. 1879 



[Price Sixpence 



Regi-rered as a Newspaper at the General Past Office.] 



[.\ll Rights arc Reserved. 



BROWNING'S ASTRONOMICAL TELESCOPES. 



The EDUCATIONAL REFLECTING TELE- 

 SCOPE, with Silvered Glass Mirror 4^ in. diameter, 

 5 ft. focus, mounted on a Parallactic Stand for following 

 the heavenly bodies with one motion by means of an 

 endless driying-screw and Hook's joint, with two eye- 

 pieceSi 



PRICE £24 4s, Od. 



Powers can be used up to 400 diameters on many 

 stars with advantage. 



LIST OF PRICES OF TELESCOPES FREE. 



Sixth Edition, with much New Matter. 



A PLEA for REFLECTORS; being a 



Description of the New Astronomical Telescopes, 

 with silvered glass specula, and instructions for using 

 and adjusting them, with many Illustrations and 

 Coloured Frontispiece of Jupiter. By JOHN 

 BROWNING, F.RA.S.— One Shilling, post free. 



JOHN BROWNING. 



OPTICAL AND PHYSICAL INSTRUMENT MAKER 

 TO H.M. GOVERNMENT, THE ROYAL SOCIETY, 

 THE ROYAL OBSERVATORIES OF GREENWICH, 

 EDINBURGH, &c., &c. 



63, STRAND, W.C, LONDON. 



Factory — Southampton Street and Exeter Street, London. 



Prize Medal, 1862. Established too Years. 



Microscopes, Spectroscopes, Spectacles, &^c., Sfc. 



