322 SEC. 10. ELECTRICITY. 



1677. Lamp, with self -registering electrical apparatus, and 

 bichromate of potash battery. Mariais. 



168Oa. First Electro-magnetieal Needle Telegraph, 



invented in the year 1830 by Baron P. L. Schilling (born in 1786 

 at Reval), consisting of: 



Two electro- magnetical alarum apparatus ; two ditto, and gyro- 

 tropes (key-board, indicator) ; one current indicator ; one multipli- 

 cator for the signs (sign receiver) of the magnetic needle to the 

 right or to the left respectively, turning of the white or black 

 side of a paper disc towards the spectator. 



Physical Science Cabinet of the Imperial Academy of 

 Sciences at St. Petersburg. 



1683. Cooke and Wheatstone's Single-Needle Instru- 

 ment. (Early form.) J. A. Warwick, Esq. 



Used by the Electric Telegraph Company in 1846 on unimportant railway 

 circuits. 



The specimen exhibited has a " crutch " handle commutator, but the more 

 general form has the " drop " handle. 



1683a. Automatic Lightning Guard. 



Warden, Muirhead, and Clark. 



1684. Galvanometer of Matteuci. 



Royal Institute of " Studii Superiori " at Florence. 



1685. Thermo-electric File of Nobili. 



Royal Institute of " Studii Superiori " at Florence. 



1686. Galvanometer of Nobili. 



Royal Institute of " Studii Superiori " at Florence. 



1687. Original Magneto-electric Machine of Nobili. 



Royal Institute of " Studii Superiori " at Florence. 



1681. Cooke and Wheatstone's Double-Needle Tele- 

 graph, with Alarum. Earliest form, with 6-inch coils and 

 astatic needles. Reid Brothers, London. 



These instruments were used on the line erected between Paddington and 

 Slough for the purpose of exhibiting the invention. 



1682. Double-Needle Instrument. As used by the Electric 

 Telegraph Company in 1846. Reid Brothers, London. 



Used for all public business, and for the principal railway circuits, with 

 6-inch coils and astatic needles. The coils were afterwards reduced to one 

 inch. The double needle was superseded for public purposes by the Bain 

 recording instrument from about 1850. It is still used by some railway 

 companies. 



