16 THE NORTH ATLANTIC TELEGRAPH. climates telegraph lines work much better than in warm latitudes. We have both in America. In the south, the wires, stretched upon the poles, in summer are often so hot that you cannot touch them without being slightly burned. During such days the conducti- bility of the wire is lessened, and so serious is the hindrance experienced, resulting from the wires becoming hot by the heat of the sun, that it is frequently found necessary to reduce the electric circuits to lengths under two hundred miles. I have closely observed the working of the lines in the northern states, when the cold was greater than is experienced in Greenland: they worked with less battery, and without interruption. During periods of severe cold the telegraph works the most successful. The North Atlantic Telegraph will be singularly blessed, both as to land and sea, with respect to temperature, and even if other things were but equal, the northern line will have great advantage in that respect over any other transatlantic route. This new discovery of the retardation of the electric current was promulgated by Professor Paraday to the Royal Institution of Great Britain, and I read it with amazement. How to meet this difficulty was the next question. We found that it required an uncertain time to overcome a distance, say 1000 miles. The cable became like a Leyden jar, the interior coating of the jar serving the same as the electric conductor inside the cable, the gutta percha as the glass, the water as a conductor of electricity on the outer part around the jar, so that the very moment that we charge the inside— the conducting medium for telegraphic purposes—that very moment nature gathers around the cable outside an opposite electricity, which serves to hinder the celerity of the interior current, designed for telegraphic communication. That was expe- rienced in the case of the late Atlantic cable. I satisfied myself then—not recently, but in 1854—that the working of a line of telegraph from Newfoundland to Ireland, a distance of 2000 miles, could not practically be consummated for commercial telegraphic purposes. As a high point in science it might be done—that I do not, nor never did deny; and even at the very time the cable was announced to be laid in America, I published a letter challenging any- body to prove that the line could be worked from Newfoundland to Ireland practically for telegraphic purposes;—the company was challenged to send through the cable as many words in twenty-four hours as could be transmitted over an air-line in five minutes ! It might be possible to send at the rate of three words per minute; but what are three words per minute ? A practical telegrapher would not require anything further to prove that such a telegraphic line could not subserve the purposes of commercial wants. It would be but like unto the “ sounding brass and tinkling cymbal ” (applause).

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