AMERICAN ELF.CTRIC-TEI.EGRArn. 275 



to lAC) lbs., but when the wire was divided into nine separate parts of 

 twenty yards each, and separately wound on the Uj^'^^ electric current 

 flowing through all simultaneously, he obtained a power equal to 750 

 lbs. This proved the possibility of making electro-magnets of almost 

 any desirable power. They have since been constructed so as, even 

 with a small battery surface, to sustain several thousand poimds weight. 

 Tlie 7nass of the conductor appears to be more important than i\\c IcHglh. 



The knowledge of these facts, together with the additional one, that 

 the electric current passes, not only with inconceivable rapidity, but al- 

 so almost unimpaired through even the longest conductors, suggested to 

 Professor Morse, on a homeward voyage from Europe, in October, 1S32, 

 the sublime idea of constructing an instrument which was to annihilate 

 both time and space by conveying intelligence by means of electricity. 

 The result was the invention, and after some modification and improve- 

 ment, the perfection of the American Electric-Telegraph. Those alone, 

 who are acquainted with the cumbersome and comparatively slow me- 

 thod of signal telegraphs previously in use, can form a tolerably correct 

 idea of the elegance and importance of such an invention. 



The batteiy and magnet, upon which the action of the instrument 

 depends, being described in a general way, it becomes necessary to take 

 up several points in detail. 



If, when a (J of soft iron is wound with an insulated copper wire 

 whose two ends are made to communicate with the extreme metals or 

 poles of the battery, an electric current is made to flow through it round 

 the U it renders it strongly magnetic. It matters not how distant the 

 battery is from the soft iron, so tliat only there is a good connection be- 

 tween them, such as is afforded by two continuous wires well insulated 

 from each other, or by one insulated wire and the mass of the earth Sec. 

 If, for instance, the battery were at Washington and the magnet at Bos- 

 ton, and a wire extended from the former to the latter and another from 

 the latter to the former, upon making the necessary connections, the bat- 

 tery at W. would instantaneously render the soft iron at B. magnetic. 

 The same would take place if an insulated wire from one end of the;, I^at- 

 tery alone extended from W. to B., provided that at the same time the 

 other end of the battery, as also the free end of the wire enclosing the 

 U , communicated with the earth : fur it has been ascertained that, as tiie 

 conducting power of bodies increases with their mass, a large conduclur 

 Avill compensate for a feeble conducting power. It is thus that the in- 

 terposed mass of earth, being of the same length as the wiic, becoujes e- 

 von a better conductor in consequence of its great mas.s •, and it is upon 

 lias principle that //uo/i iion wiitb can be substituted for copper, allho^ 



