264 C. F. GAUSS ON A NEW INSTRUMENT FOR OBSERVING 



that with our simple chain and the arrangement of the ap- 

 paratus then adopted, (such experiments being merely a sub- 

 ordinate object) no more than two letters could be signaled 

 in a minute. Even with the new ari'angement expressly form- 

 ed for the purpose, this velocity (which is obviously uncon- 

 nected with the length of the chain, or the distance apart of its 

 extremities,) could not be considerably increased as long as only 

 a simple chain was employed, though it would be increased to a 

 very high degree with a compound one ; but there was no suf- 

 ficient reason in this case for estabUshing a chain of the latter 

 kind, as there could be no doubt as to the result, and its real 

 scientific value would have borne no proportion to the expense. 

 But the laws of induction have led me to a quite different 

 method, in which a simple chain has been employed for more 

 than two years, with complete success, for a much more rapid tele- 

 graphing. It will be the more allowable to dwell longer on this 

 subject, as hitherto I have published no details concerning it. I 

 have elsewhere described*, many years ago, the apparatus which I 

 term inductor. I must however remark, that instead of the in- 

 ductor of 1050 coils described in the first notice, and of that subse- 

 quently increased to 3537 coils, the present one consists of 7000 

 coils, — the length of the wire alone amounting to more than 7000 

 feet. By a very simple manipulation with this inductor, (viz. by 

 removing it quickly from a double magnet bar, on which it is at 

 first placed, and then bringing it back immediately to its former 

 position, without reversing it,) two powerful opposite galvanic cur- 

 rents are caused to pass through the conducting wire, one quickly 

 after the other, and each lasting only an extremely short time. 

 The effect of these two currents upon a magnet bar surrounded 

 by a multiplier, and situated anywhere in the chain, consists in 

 this : that it produces for a moment a very quick velocity, which 

 is immediately destroyed. The needle, therefore, makes a very 

 rapid but small movement either to the right or to the left, ac- 

 cording as may be desired, and then is immediately at rest. It is 

 evident that the changes of such rapid movements may be com- 

 bined in various ways, and may be employed for signahng letters. 

 Some degree of practice will of course be required to give the 

 signals rapidly and pi'ecisely on the one hand, and on the other 

 to read them with ease and certainty j but even by unpractised 



* GiJff. gdehrlen Anxeige, 1835, p. 351 ; Schumacher's Jakrbuch for 1836, 

 p. 41. . 



