396 THE POPULAR SCIENCE MONTHLY. 



" Yes, just as mucli room as ever, as mucli room as the whole 

 earth offered to the first man " ; for that field is simply unbounded, 

 and everything that has been done in the past is, I believe, as 

 nothing to what remains before us. 



The days of hardest trial and incessant bewildering error in 

 which your elders have wrought seem over. You " in happier 

 ages born," you of the younger and the coming race, who have a 

 mind to enter in and possess it, may, as the last word here, be bid- 

 den to indulge in an equally unbounded hope. 



\^Concluded.'\ 



GAUSS AND THE ELECTRIC TELEGRAPH. 



WE have been favored with the following interesting letter, 

 giving some facts in relation to Prof. Gauss in addition to 

 the sketch of this distinguished mathematician which appeared 

 in " The Popular Science Monthly " for September, 1888, and in- 

 closing the appended extracts from letters by Gauss in regard to 

 his invention of a form of electric telegraph : 



Denver, Colorado, October S4, 18S8. 

 De. W. J. TouMANS, New Yorh. 



Dear Sir : Please allow me, as a grandson of Carl Friedrich 

 Gauss, the German mathematician, to thank you for the sketch 

 of his life and works which appeared in the September number 

 of "The Popular Science Monthly." I should have made this 

 acknowledgment long ago, and intended doing so, but for vari- 

 ous reasons postponed it from time to time, for which I beg your 

 pardon. 



There are two slight errors in your article, one, at least, of 

 which is hardly worth mentioning. The first is in regard to the 

 date of Prof. Gauss's birth. " The Popular Science Monthly " arti- 

 cle says that he was born on April 23, 1777. In fact, however, he 

 was born on April 30th of that year. 



The other error amounts to little, but perhaps you may think 

 it worth correcting. You say that he and Prof. Weber sent tele- 

 graphic signals from Gottingen to a neighboring town. They 

 were, in fact, sent only from the astronomical observatory to the 

 physical cabinet, which was under the direction of Prof. Weber ; 

 this was in 1833. The wire used was about eight thousand feet 

 long ; it was destroyed by a stroke of lightning in 1845. On pages 

 64 and 65 of "Gauss zum Gedachtniss," by W. Sartorius von 

 Waltershausen, there is a description of this telegraphic line. In 

 a work entitled, I believe, " Electricity in the Service of Man," 

 there is a picture of the telegraphic apparatus used by Gauss and 

 Weber. 



