1857.] Mr. WaringCon, on the Aquarium. 4Q3 



Mr. Faraday occupied a few minutes at the commencement of 

 the evening in giving a brief account of Mr. C. V. Walker's mode 

 of telegraphing electrically from one station on a railway to the 

 next on either side ; or from a break-down on the rail to either of 

 these stations. Signal bells are arranged at such stations, each 

 with its own battery ; and the latter, being connected with the 

 earth at one of their ends, are connected together at the other ends 

 through the bells and the telegraph line ; but so that the batteries 

 are opposed to each other as to the currents they can produce : 

 hence there are no currents, and the bells do not ring. But when 

 the wire between the bells is connected with the rail or the earth, 

 then both batteries can send forth their currents and both bells are 

 rung. This necessary earth connexion can be made at one station, 

 and then the bell rings at the next. If a break-down occurs, the 

 guard connects the telegraph wire where he is with the rail or 

 earth, and the stations on both sides of the accident are warned. 

 Provision is made at some of the line posts, about a furlong apart, 

 where the man, by touching a key, can at once give the notice 

 required. The method was illustrated by experiments with the 

 bells and wire arranged by Mr. Kichard'Knight. 



Mr. Gassiot's great induction coil was also exhibited and 

 referred to by Mr, Faraday, who described its particular points as 

 to insulation, &c., and showed some of its fine results. 



[M. F.] 



WEEKLY EVENING MEETING, 



Friday, March 27. 



The Duke op Northumberland, K.G. F.E.S. President, 

 in the Chair. 



Robert Warington, Esq. 

 On the Aquarium. 



The speaker opened the evening's demonstration, by stating that he 

 had immediately responded to the invitation of the Managers of 

 the Royal Institution to deliver this discourse, on what they had been 

 pleased to call his " own subject," from the feeling, that as the 

 originator of the aquarium, he was in duty bound to afford, to all 

 those who had taken up this " new pleasure," every assistance, from 

 the results of his own experience, that lay in his power, in order to 

 render the undertaking more easy and pleasurable ; and for this 



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