The above represents the telegraphic characters marked upon the prepared fabric. The spaces are numbered from the top. The first six of the telegraphic letters require each a signal wire, and the common wire, D, with one battery. The next six require each two signal wires, with two batteries, whose joint currents pass in the same direction on the common wire, D. The next six require each two signal wires only, with two batteries, joined together so as to form a compound battery. The negative pole of one, connected with the positive pole of the other. The next two require each three signal wires, with three batteries, whose joint currents pass in the same direction along the common wire, D. The next six require each, three _signal_ wires only, with three batteries. One of the signal wires with its battery is used as a common wire for the other two. Hence the current of the two batteries of the two signal wires unite in one, and are connected with the battery of the common wire as a compound battery. With what rapidity these letters may be formed, does not appear, or to what extent the plan has been carried out. _Bain’s Printing Telegraph._ The following description of Mr. Bain’s plan of what he calls an _electro magnetic_ printing telegraph, is taken from a work entitled, “An account of some remarkable applications of the electric fluid to the useful arts, by Alexander Bain. Edited by John Finlaison, Esq. London, 1843.” It appears from this work that Mr. Bain’s plan was invented in 1840, and the following certificate is given in reference to the date of its first operation. PERCEIVAL STREET, CLERKENWELL, _Aug. 28, 1842_. DEAR SIR—In reference to your application, I recollect visiting you at your apartments in Wigmore street, early in July, 1840, when you showed me the model of your _electro magnetic_ printing telegraph, with which you printed my name at the time. You also showed me a model of your electro magnetic clock, and explained to me the principles and utility of them. I remain, dear sir, yours, respectfully, ROBERT C. PINKERTON. To MR. ALEXANDER BAIN. [Illustration: FIG. 76. PORTSMOUTH.] [Illustration: FIG. 77. LONDON.]