NATURAL PHILOSOPHY. 119 



telegraphing." It is stated that the expense for the recording fluid 

 will be less than one cent per day. Washington Republic. 



Electro-thermic telegraph. Mr. W. S. Thomas, of Norwich, N. Y., 

 has patented a new telegraph, which is an application of heat as a sub- 

 stitute for electricity in recording telegraphic communications. Heat, 

 generated by the electricity passing over the wires, is used for making 

 and recording the letters of the alphabet. The electricity, after it 

 reaches the recording instrument, is conducted on to an attenuated pla- 

 tinum point, in contact with the paper, which becomes instantly 

 heated, or as sudden!)*- cold, as the circuit is made or broken, and thus 

 the necessary mark is made. Common dry paper may be used, but 

 that chemically prepared is better. Farmer and Mechanic, Feb. 21. 



The London Builder for April describes a new telegraph, invented 

 by Mr. A. Mitchell, for transmitting messages and news by means of 

 one wire. Like House's telegraph, it is worked with keys after the 

 manner of a piano-forte, the only difference apparently being, that, in- 

 stead of printing the letters, a finger is made to point to them on a dial 

 on which they are arranged in order. 



Henley 's Magneto-electric Telegraph. An experiment has just 

 been made, under the direction of the French government, to test the 

 efficacy of Mr. Henley's magneto-electric telegraph, which is worked 

 without batteries of any kind, and at a fraction of the cost of the vol- 

 taic system. The line of railway assumed for the trial was that from 

 Paris to Valenciennes. The persons present at the two stations were 

 the director of the French telegraph, a commissioner appointed by the 

 Belgian government, and a few others. The distance is 180 miles, 

 being the longest telegraph line in France. After a most satisfactory 

 series of trials on the single distance, first with full power, and after- 

 wards with one twentieth of the power, the wires were connected so as 

 to treble the total length of wire, making 540 miles to and from Paris 

 and back, the magnetic message being communicated through the first 

 wire, back by the second, through the third, and back again by the 

 earth. It was not anticipated that the magnet could possibly work 

 through this resistance ; but, in fact, it is alleged it was worked as 

 distinctly and rapidly as when only made to traverse the 180 miles 

 with full power. The ordinary telegraph, with battery power, used 

 by the French government, was then put in requisition ; but not the 

 slightest effect was produced. On the single distance even, a signal 

 was sometimes not obtained for several minutes, owing, it is said, to 

 some fault in the batteries. The government officers and others in- 

 spected the working operations, and expressed themselves thoroughly 

 satisfied with the success of the trial. London Mining Journal. 



Telegraphic Manipulator. Mr. Edward Everett, of Illinois, has in- 

 vented a " telegraphic manipulator," which may be used either with 

 Morse's or Bains's method of communication, as it impresses on paper, 

 by a neat and simple mechanism, the dots and marks, which, by both 

 these methods, constitute the telegraphic alphabet. The process of 

 writing by this alphabet has hitherto been the work of great skill, re- 

 quiring long practice before the art can be acquired, and great mental 

 effort for giving to each dot, line, and intervening space its proper 



