Bankers & Brokers Telegraph line uses glass insulators

THE BANKERS' AND BROKERS' TELEGRAPH COMPANY, office No. 14 Broad street, New York, having completed their line from Washington to New York, laid on the 10th inst. Across the North River, at Fifty-ninth street, two of their new submarine cables. The line is constructed throughout in the most substantial and enduring manner. No cost has been spared to make it the model line of the country. Mr. Charles Ottinger, the Company's engineer, assisted by Mr. Butterfield, who has charge of the cables, successfully laid the two cables - one in thirteen and the other in sixteen minutes - with their new and splendid scow and fine large reel made for this purpose, the laying being done in fine shape. This Company is composed of some of our best men. Mr. William Callow, the President, is an old Baltimorean, formerly of the firm of E. Pratt Co.; Mr. G. Hilton Scribner, of New York, is the only resident director at present. These cables are from the works of the Bishop Gutta Percha Company of this city, and were made with great care, under the direction of Samuel C. Bishop, the general agent of the Company. They were thoroughly tested and found very perfect. From the agent of the Company we learn the construction of these cables is as follows: "The Conductor is three No. 19 copper wires twisted together, rope fashion, making one conductor equal to No. 14 wire gauge. The insulation is of pure Gutta Percha, laid on in three coatings making nine-sixteenths of an inch diameter outside. The bedding is of 2-yarn Manilla, laid on spirally, having two coverings reverse way, and the armor is fourteen No. 4 galvanized iron wires laid up spirally. The whole cable weighs about 13,500 lbs. (near 7 tons) to the mile.

"The materials and workmanship of these cables, are very superior, and we think cannot be surpassed, if equaled anywhere, even in England. They are of very great strength, and will successfully resist hauling up by almost any ship on the river. The insulation is extra heavy, and the bedding having two layers of Manilla yarn reversed, affords a fine protection for the gutta percha. We find Manilla yarn without tar far superior for durability in water to tarred hemp. We have seen tarred hemp entirely decayed and rotten in salt water, after three to four years time, while Manila yarn, without tar, was as fresh and good, and strong as when laid down. (We have always advocated Manilla yarn, and recommended it for bedding in preference to tarred hemp.) The old aid first Fortress Monroe cable we made in 1862 has been sent back to us by government to strip and keep the core for future use, and the gutta percha insulation and the Manilla yarn bedding is as good as when made in 1862, while the iron armor is entirely rusted out and worthless (it was plain and not galvanized wire.) Tar, under some circumstances, will dissolve gutta .percha, and should never be placed near it, especially should it not be compounded with gutta percha rfo [sic] for an insulation, we think."

These lines are built on a new plan. There are two sets of poles with two wires six feet apart on each set, which run upon entirely different routes, meeting at stated points for tests and connections. This will probably prevent "crosses," and enable the Company to have at least one or two of its wires always working.

The arms or brackets are saturated with coal tar and fastened to the poles in a very secure manner. The insulators used are the common glass ones, put upon pegs, besmeared with white lead, projecting from the bracket. All metallic connections for securing the wires to the poles are avoided, and a non-conductor is used in addition to the regular insulation. It is hoped this plan will prove valuable, but must of course be thoroughly tested to prove its efficiency.

This Company do not intend to have any "way stations," or take any "way business," but will have three stations between each main office, for tests alone.

This Company will soon commence constructing their lines south of Washington, and will connect with lines now building west from this city and Philadelphia.