Mr. Bain's telegraphs have been exhib ited before the French government, and will form the medium of telegraphing in that republic. On that occasion, a com mittee of the French Legislative Assem bly, at the head of which was the cele brated astronomer, Le Verrier, was ap pointed to investigate the merits of this invention. They caused the experiments to be repeated in their presence. A mes sage consisting of several thousand words was transmitted to Lille and back along a single wire (the wire being united at Lille so as to carry back the message), at the rate of about 1,500 letters, or nearly 400 telegraphic words per minute. The committee reported favorably of the pro ject, and the government ordered a set of apparatus to be constructed, to be placed in the first instance on the line between Paris and Calais. This line was com pleted in the early part of last year (1850), and their performance was witnessed by the correspondent of a London journal.' His own dispatch was transmitted and written by the apparatus in his presence at the rate of 1,000 letters per minute, probably as quick as messages will be transmitted by it. The characters were perfectly distinct, and the dispatch was read from them also in his presence. This speed is not always attained. Bain's • telegraph is not worked in this country any quicker than Morse's. In both cases the rapidity depends on the skill of the operator.
Bain's telegraph not only prints, but makes marks of a chemical nature, in character nearly like that of the Morse telegraph, but no "electro-magnet" is used except to rectify operators. By breaking and closing the circuit at New-York, the pen which is in contact with chemically prepared paper at Philadelphia, makes blue marks on the paper, and these blue marks make the message. There is one part of this in vention which is a curiosity in its way. The operator writes the message first on a strip of paper, by perforating it with small holes, for the dashes and the dots, and by making this, in a very ingenious manner, 'break and close the circuit, a message may he transmitted to anyplace. When there is time to prepare messages, this is a ready way to transmit them ra pidly. This invention embraces the idea of printing a pattern of calico in Philadel phia by breaking and closing the circuit in New-York.
O'Reilly's Telegraph. This is not strict ly a distinct telegraph, but a line of tele graphic communication established by Mr. O'Reilly, in which he avails himself of the Morse line over most of the dis stances, as from New-York to Louisville: thence to New-Orleans, Bain's telegraph is used now, it having replaced Messrs. Zook and Barns' apparatus, a form which has not been patented, but which had been in operation on that line. The O'Reilly lines extend, besides the two distances mentioned, from Pittsburg to Cleveland and Detroit: from Dayton, 0.,
by Lake Erie to Chicago : from the Ohio River to Evansville, connecting the pre vious line at Terre Haute : and from St. Louis to Dubuque, Iowa, supplying the intermediate cities. The INew-Orleans route divides into two branches, one of which proceeds by Tuscumbia, Alabama, to Memphis ; the other proceeds front Jackson, Miss., to Vicksburg, making a total distance in the southern route of 1,100 miles. On this line also, the naked iron wire is used, it being found to net as a better insulator than the galvanized wire, for, in the latter instance, when the wire is touched by leaves of trees, which is unavoidable in many places, the cur rent is conveyed off the polished metal, but if the wire be rusted, it becomes in sulated by that means, and the current suffers less interruption.
The following was the extent of tele graph communication in this country, Nov. 1847:— New-York to Buffalo 509 Troy to Saratoga 86 Auburn to Elmira 54 Ithaca to Binghampton 46 Syracuse to Oswego ..... 33 Buffalo to Chippewa, C. W. 12 Queenstown to Toronto 150 Hamilton to London 75 Toronto to Montreal 376 Montreal to Quebec 180 New-York to Washington, D.0 224 Washington to Petersburg 175 'Philadelphia to Pittsbnrg......... 296 Philadelphia to Pottsville 106 *Lancaster to York 25 Pittsburg to Cincinnati.... 120 Massillon to Cleveland 136 Cincinnati to Louisville, Ky 55 New-York to Boston. 237 Boston to Lowell. ' 26 'Boston to Portland, Maine 74 Total 2969 Contemplated then, since perfected.
Petersburg to New Orleans ......... 1427 Butrallo to Detroit 350 Detroit to Milwaukie 350 Bridgeport to Montreal 300 Norwich to Worcester 95 Louisville to St. Louis 300 2812 From Macon to Flanepec... .
St. Louis to New-Orleans 1000 2000 The line is c.ouble nearly the whole way, one wire connecting each interme diate place, and one connecting the ex treme points. These lines to which as terisks are appended are also used by the O'Reilly line.
The foregoing are on the Morse princi ple, which, with a few minor lines. bring up the whole extent of the Morse lines to nearly 12,000 miles, and there are shout 2.000 on House and Bain's principles. The telegraph now extends from Halifax to New-Orleans, and as far west as Du buque, Iowa, making an extent of 22,000 miles.
A contract has been entered into by the Mexican Government with Wm. George Stewart, Esq., the Mexican consul at New-York, and Senor Juan dela Granja, of Mexico, to build a line from Vera Cruz to the city of Mexico—a distance of three hundred miles—on the understanding that it will be in operation by the first of May, 1852, as far as El Ojo de Ague, a distance of one hundred and twenty miles from the latter place. Another line will soon after be built between Aca pulco and the city of Mexico. When both are completed there will be magnetic communication between the Atlantic and the Pacific.