i'02 



SCIENCE. 



[N. S. Vol. IX. No. 229. 



Petersburg, und eiue Copie fiir Herrn Sartorius blieb 

 bier, wonach jene Litliographie geraacbt ist. Man 

 fand das Geiujilde damahls sebr iibiilicb ; jetzt -nerde 

 ioh ihm wobl uniihnlicb geworden sein. 



Auch fiir die Karte von Missouri und Arkansas, 

 welobe mit jenem Bilde zugleich aukam, babe icb 

 Dir nocb zu danken. 



Uass Ewald nocb im vorigen Jabre slob wieder 

 verbeiratbet bat, wird Dir wahrscheinlicb die Gross- 

 mutter gesobrieben baben. Mit berzlicben Wiinscben 

 fiir Dein Woblergelien 



Dein treuer Vater, 



GoTTiNGEN, C. F. Gauss. 



den 9ten August, 1846. 



An account of Gauss's children is inter- 

 esting from the standpoint of heredit3\ 

 ISTone inheritedGauss's mathematical power. 

 Eugene resembled his father mentally more 

 than the others. Like his father, he pos- 

 sessed great linguistic powers. Before his 

 death he expressed it as his opinion — and 

 from all I can gather it is probable — that had 

 he continued his philological studies in Ger- 

 many he would have secured a chair in a 

 Universitj'. He spoke French so well that he 

 was taken for a Frenchman. The English 

 and the Sioux language he spoke to per- 

 fection. He read the New Testament in 

 the original. At the age of forty he had 

 become deeply interested in religion, and 

 thereafter he gave much attention to Bibli- 

 cal and theological reading. His deep re- 

 ligious convictions were shown by his ex- 

 pression of satisfaction with his coming to 

 America, because if he had not done so he 

 might never have been led to profess the 

 religion of Christ. 



Eugene was not the person to push him- 

 self to the front. He lived over ten years 

 near the seat of the University of Missouri, 

 without seeking the acquaintance of any 

 member of the FacultJ^ Milton Updegraff, 

 the professor of astronomy, accidentally 

 heard of him through one of his students 

 and visited him (about 1890). He told 

 Professor Updegraff that his father first 

 thought of the heliotrope while walking 

 with him and noticing the light of the 



setting sun reflected from a window of a 

 distant house.* Eugene possessed mathe- 

 matical ability, but he never studied the 

 higher branches. When he was over eighty 

 years old and had become blind, he used to 

 entertain himself by making long arithmet- 

 ical calculations in his head. For instance, 

 he computed the amount to which one dollar 

 would grow, if compounded annually at the 

 rate of 4% interest from the time of Adam to 

 the present, assuming this to be 6,000 years. 

 This, if in gold, would make a cubic mass 

 so large that it would require light quad- 

 rillions of years to pass along one side of it.f 

 This mental computation is so startling as 

 to be almost beyond belief. The only as- 

 sistance he had was from his son Theodore 

 (now deceased), who was asked to write 

 down, at intervals during the several days 

 he was so occupied, the results that marked 

 the different stages of his work. Eugene 

 arrived at his result by ordinary arithmetic. 

 His son preserved the paper on which were 

 written the long lines of figures which he 

 thought he might not be able to retain in 

 his memory. On the sheet are several 

 memoranda that are interesting. For in- 

 stance, Eugene directed his son to write 

 down the figures : 



123456789057182178039 



3680824926969613857 



123456789060863002965969613857 



The second line of figures was written 

 down several days after the first and added 

 to the upper one by Theodore. His father 

 had directed him to begin the second line 

 of figures by placing the figure 3 under the 

 second 7 of the upper line. In reading off 

 the result of this addition Theodore read 7 

 in place of the 8 marked with an X. Eugene 

 detected the error and his son made the 



'•■■ See also Bessel's letter to Gauss, Oct. 18, 1821. 

 fTbe answer exceeds five quadriJlions of years, 

 Frencb numeration. 



