WILLIAM .S7AM//..Y.S, /.A'..V. 45 



simplicity and speed. There might bo some degree of force in 

 that argument in regard to this country, where the lines were 

 Comparatively short, but a needle telegraph was certainly in- 

 admissible for long and international lines of communication. 

 The defects of the needle telegraph system in this country were, 

 however, sufficiently manifest, from the distortion of names and 

 figures which occurred in almost every message received. Mr. 

 Siemens could not admit Mr. Highton's argument against the 

 application of magneto-electric and induced currents. Their 

 failure in all the early attempts had been admitted in the paper 

 and might be very clearly traced to the short duration of the induced 

 current, which rendered it unfit to exercise any sustained or 

 visible mechanical effect upon the receiving instrument ; but he 

 mentioned that, in the construction of the instruments he had 

 placed before the meeting, a new and most important feature had 

 been introduced, that of sustaining the effect produced by an in- 

 stantaneous current, by means of permanent magnets, the in- 

 stantaneous line-wire current being only required to disturb for 

 an instant of time the equilibrium between two equal and con- 

 tending poles. Instruments constructed upon this principle 

 required no adjustment according to the distance and other cir- 

 cumstances, which was another very important point, and there 

 was hardly any limit to be assigned to which the delicacy of the 

 instrument might not be carried. The chief advantage of induced 

 currents for submarine lines consisted, however, in their perfect 

 equality. Respecting the new dial instrument he wished to draw 

 the attention of the meeting to the means adopted to obtain 

 quantitative induced currents by the application of a series of 

 permanent magnets acting in close proximity upon a long rotating 

 keeper of the section of the letter H, into the recesses of which 

 the induced wire was coiled, by which arrangement a powerful 

 alarum might even be sounded at a distance of 500 miles, to which 

 distance these instruments worked with absolute certainty. The 

 dead-beat ratchet-motion was also of peculiar construction, whicli 

 rendered the slip of a tooth impossible even at the highest velocity 

 at which the handle of the instrument could be worked. The 

 mode of receiving messages by touch, which had been mentioned 

 by Mr. Varley, was not new, the same plan having been proposed 

 by Vorsselmann de Heer (see " Pogg. Ann." vol. 46, page 513) in 



