HENEY AND THE TELEGRAPH. 809 



'' The experiments alluded to were tried on Tuesday, and with per- 

 fect success. I had prepared a galvanic battery of three hundred pairs, 

 in order to have ample power at command ', but to my great gratifica- 

 tion, I found that one hundred pairs were sufficient to produce all the 

 effects I desired through the whole distance of one hundred and sixty 

 miles. It may be well to observe that the hundred and sixty miles of 

 wire are to be divided into four lengths of fortj" miles each, forming a four- 

 fold cord from Washington to Baltimore. Two wires form a circuit ; the 

 electricity therefore in producing its effects at Washington from Balti- 

 more, passes from Baltimore to Washington and back again to Baltimore, 

 of course travelling eighty miles to iiroduce its result. One hundred 

 and sixty miles therefore gives me an actual distance of eighty miles ; 

 double the distance from Washington to Baltimore. The result then of 

 my exjieriments on Tuesday, is that a battery of only a hundred i^airs at 

 Washington, will operate a telegraph on my plan eighty miles distant 

 with certainty, and without requiring any intermediate station." 



As it was part of the original plan (as set forth in the caveat of 1837) 

 to lay the conducting wires underground, Professor Morse, in 1843, de- 

 vised a method of forming a lead pipe around the group of jirepared and 

 insulated wires, that is of introducing the compound cord into the pipe 

 in the process of its construction. He obtained a patent for this project 

 October 25, 1843, (No. 3316,) claiming " the method of introducing wires 

 into hollow i)ipes whilst making the same, by introducing the wires 

 through a hollow mtindrel on which the pipe is made." This process 

 was practically carried out, though with the extreme risk of constantly 

 impairing the insulation of the wires by the ©iieration. 



Professor Gale has given the following account of the method of lay- 

 ing the telegraph line and of the result. "A plow was used, with a share 

 running two and a half feet deep, and carrying a coil of insulated wire 

 inclosed in a coil of lead pipe which the plow deposited in the ground 

 and covered as the plow progressed. Forty miles of lead pipe were made 

 in New York in the autumn of 1843, and shipped to Baltimore in the end 

 of November. Up to this date I had been engaged in New York inspecting 

 the manufacture of the lead pipe and charging the same with the iusulated 

 wire fed into the pipe by machinery while the pipe was drawn. I reached 

 Baltimore in the early -pavt of December, and learned that the jjarty had 

 nearly reached the Relay House. Nine miles had been laid ; on inspection 

 of which, not one mile of wire was found to be sufiiciently insulated to 

 carry the electric current from end to end of the reach."* 



The plan was finally abandoned early in 1844, after more than half of 



* Morse Memorial, Washington, 1875, pp. 18, 19. Steinheil, in 18157, remarked: "Nnmer- 

 ous trials to insulate wires and to condnct them below the snrlace of the gronnd have 

 led me to the conviction that such attempts can never answer at great distances, in- 

 asmuch as our most perfect insulators are at best but very bad conductors. And since 

 in a wire of very great length the surface in contact with tlie so-called insulator is 

 uucommonly large when compared with the section of the metallic conductor, tluTO 

 necessarily arises a gradual diminution of force." (Sturgeon's Annals of Electricity, 

 etc. April^ 1839, vol.'iii, ]>. 510.) 



