XI. APPLICATIONS. 375 



1695a. Model of Aerial Telegraph, by Chappc. 



Telegraphs Department, Paris. 



1695b. Model of Aerial Telegraph, by Monge. 



Telegraphs Department, Paris. 



1695c. Model of Aerial Telegraph, by Breguet and 

 Bettancourt. (This model belongs to the Conservatoire des Arts 

 et Metiers.) Telegraphs Department, Paris. 



1695d. Model of the First French Electric Telegraph, 



with two needles. Telegraphs Department, Paris. 



1695e. Electric Telegraph, by Hughes, with latest improve- 

 ments. Telegraphs Department, Paris. 



1695f. Autographic Apparatus, by Meyer, constructed by 

 Mr. Hardy. Telegraphs Department, Paris. 



1695g. Froment's Dial Telegraph. 



Telegraphs Department, Paris. 



SPECIAL APPLICATIONS. 



1576 d. Electric Fire Alarum, for warehouses, &c. 



The British Telegraph Manufactory, Limited. 



1696. Electric Alarum for indicating the heating of 

 Axle Bearings. C. $ E. Fein, Stuttgart. 



This is intended to show the heating of an axle in its bearings, and for 

 this purpose is placed in an opening in the cap piece, so that its lower end 

 touches the axle. As soon as the temperature rises, contact is made and a 

 bell rings. The metal of the bearings, plummer block, &c. serve instead of 

 return wires, so that only one insulated conductor is required. 



1697. Group of Apparatus, comprising an electric control 

 clock, with six locking signal studs. C. fy E. Fein, Stuttgart. 



This is for use in manufactories, public buildings, &c. The dial is a paper 

 Jisc, which is changed daily, and revolves once in 12 hours ; it contains 

 as many rings as there are stations. By pressing down a knob at any of the 

 stations an electro-magnet inside the clock draws its anchor forward, and a 

 mark is made on the dial. As the dial is very large, minutes can be read 

 off easily. When a new dial is put on, the knob in the centre is to be turned 

 so as to set the clock to the right time. The clock will go for several days, 

 but it is better to wind it up daily. The signalling knobs can be kept locked 

 up, and may be opened by the watchman with a key which is common to the 

 whole apparatus. 



1698. Battery Case, containing six large Meidiuger's cells 

 for working the above apparatus. C. $ E. Fein, Stuttgart* 



1699. Lamp with Double Screen, slide and adjustable lens, 

 scale stand, scale, &c. To be used with reflecting galvanometers 

 generally. Elliott Brothers. 



