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the telegraph, where a discharge, falling on the wire near the station, 

 might send a current into the house of sufficient quantity to produce 

 serious accidents. The fate of Professor Richman, of St. Peters- 

 burg, should be recollected, who was killed, by a flash from a small 

 wire, which entered his house from an elevated pole, while he was 

 experimenting on atmospheric electricity. 



The danger, however, which has been apprehended from the elec- 

 tricity leaving the wire and discharging itself into a person on the 

 road, is, I think, very small; electricity, of sufficient intensity to 

 strike a person at the distance of eight or ten feet from the wire, 

 would, in preference, be conducted down the nearest pole. It will, 

 however, in all cases, be most prudent to keep at a proper distance 

 from the wire during the existence of a thunder storm in the neigh- 

 bourhood. 



It may be mentioned as an interesting fact, derived from two inde- 

 pendent sources of information, that large numbers of small birds 

 have been seen suspended by the claws from the wire of the tele- 

 graph. They had, in all probability, been instantaneously killed, 

 either by a direct discharge, or an induced current from a distant 

 cloud, while they were resting on the wire. 



Though accidents to the operators, from the direct discharge, may 

 be prevented by the method before mentioned, yet the effect on the 

 machine cannot be entirely obviated; the residual current which es- 

 capes the discharge along the perpendicular wires, must neutralize, 

 for a moment, the current of the battery, and produce irregularity of 

 action in the apparatus. 



The direct discharge fi'om the cloud on the wire is, comparatively, 

 not a frequent occurrence, while the dynamic inductive influence 

 must be a source of constant disturbance during the season of thun- 

 der storms; and no other method presents itself to my mind at this 

 time for obviating the effect, but that of increasing the size of the 

 battery, and diminishing the sensibility of the magnet, so that, at 

 least, the smaller induced currents may not be felt by the machine. 

 It must be recollected, that the inductive influence takes place at a 

 distance through all bodies, conductors and non-conductors; and 

 hence no coating that can be put upon the wire will prevent the for- 

 mation of induced currents. 



I think it not improbable, since the earth has been made to act the 

 part of the return conductor, that some means will be discovered for 

 insulating the single wire beneath the surface of the earth ; the difli- 

 culty in effecting this is by no means as great as that of insulating 



