AUTOGRAPHIC TELEGRRAPHY.

Thames Star, Volume X, Issue 3122, 19 February 1879, Page 1

AUTOGRAPHIC TELEGRRAPHY.

Autographic telegraphy,'or the process of transmitting messages in the actual handwriting of the* sender, f has occaaionallj during the past thirty years con* stituted the special study of scientific minds. So long since as 1850 Mr"P. C. Bakewell invented* copying telegraph by means of which autographic telegraphy was effected,'and this was probably the first time it was effectually accomplished. In this instance the inejaage was written by the sender with a gummy ink pr .Tarnish on metallic paper or tin foil, and this writing was by the aid of mechanism used to actuate electric currents in such a way as to produce a record at the distant station by the chemical decomposition of a solution with which, the receiving paper was damped. Both the written message and the paper were fixed around cylinders of similar form, and dimensions, , one being placed in the transmitting and the other in the recording * instrument, and- the cylinders were caused to revolve with corresponding velocities. Each time the gummy and, consequently, raised lines of the writing were crossed by a pointer under which the metallic paper was traversed in the transmitter, a mark corresponding in position was made on the prepared paper at the receiving end. It therefore followed that the sum of all the marks reproduced the writing itself. Mr Bakewell successfully reproduced the writing in white on a blue ground, but the process failed to become of public utility owiag to the extreme slowness with which the apparatus worked and the difficulty that was .experienced in maintaining uniform and synchronous motion'in the instruments. In 1856, the Abbe Caselli,' in Italy, endeavoured to solve the problem of auto** graphic telegraphy in a similar manner. His apparatus was exhibited in England, and it was used practically between Paria and Marseille s and Paris and Lyons. Plans, drawings, and autograph sketches were faithfully reproduced at different places, but it was found that the apparatus had not only the defects of Bakewell's, but ie was very costly and complicated. Two other subsequent workers in this direction were M. Meyer and M. Lenoir, who tried to accomplish the same results with ordinary ink. They, however, pursued | their investigations quite independently of and unknown to each other. We have recently been afforded the opportunity of examining the latest example of this class of apparatus at the General Post-office, where it has been submitted to the authorities for trial. This is the invention of M d'Arlincourt, of Paris, and its general principles are similar to those which govern Bakewell's system. The distinguishing feature in D'Arlin* court's apparatus, however, is the introduction, of an extremely ingeni us synchronous movement, by means of which the of travel of the cylinders is rendered uniform, both in the transmitting and the recording machine. The message to be sent, which may be either in the ordinary hand or shorthand, is written with a thick gummy ink upon a strip of metallic faced paper about lain. lon* and 2|>n: deep, which is wrapped around the cylinder of the transmitting instrument. A strip of white paper ehemie»lly pre«

ptred and of similar dimensions is placed on Ilie cylinder of tbe recording apparatus, and tbe instruments are placed in electrical connection and started. The raised writing, actuating the electric current, causes a reproduction of the original message in fac simile on the paper in the recording instrument, which may be hundreds of miles away from the other. Upon .the occasion of our visit the two instruments, although in the same room, were .practically placed 200 miles apart. The wiiting can be in either blue, brown, red, or black, according to the chemical preparation of the paper, but always on a white ground, and a number of copies can be taken from one original. In the same way, sketches, plans, or drawings may be faithfully transmitted; some sketches were, in fact, accurately reproduced on the occasion of our visit. Although the apparatus is perfect in its action, it still has one drawback, which was common to its predecessors—that of slowness of reproduction. The time occupied in revolving the cylinder a sufficient number of times to allow the pointer to traverse the whole surface of the paper is seven minutes, and this rate of speed is far below that required and attained in practice for commercial purposes. The Post-office authorities, to whom we are indebted for our inspection, do not, therefore, see their way to utilize M. d'Arlincourt's ingenious invention at present. It is, however, being worked in France in fortresses and for similar military purposes, for use in which and in aome special cases it is exceedingly well adapted.—Times.