SCIENCE 



Editorial Cojimittek : S. Nkwcomb, Mathematics ; E. S. Woodwaed, Mechanics ; E. C. Pickkrinq 



Astronomy; T. C. Mendenhall, Physics; R. H. Thueston, Engineering; Ika Remsen, Chemistry; 



J. Le CoNTE, Geology; W. M. Davis, Physiography; Heney F. Osboen, Paleontology; W. K. 



Beooks, C. Haet Mekeiam, Zoology; S. H. Scuddee, Entomology; C. E. Bessey, N. L. 



Beitton, Botany; C. S. MiNOT, Embryology, Histology; H. P. Bowditch, Physiology; 



J. S. Billings, Hygiene; J. McKeen Cattell, Psychology; Daniel G. Bein- 



TON, J. W. Powell, Anthropology. 



Friday, May 19, 1899. 



CONTENTS: 

 ■Carl FriedrkJi Gauss and his Children : PeOFES- 

 SOE Floeian Cajoei 697 



The Age of the Earth as an Abode fitted for Life 

 (II.): LoED Kelvin 704 



Mental Fatigue : De. Edward Thoendike 712 



Scientific BooJcs :^ 



Patten on the Development of English Tliought : 

 Peofessoe R. M. Wenley. Peruvian Meteor- 

 ology : R. Dec. Ward. Morgan on the Elements 

 of Physical Chemistry: Peofessoe Haeey C. 

 Jones. Books Received 713 



. Scientific Journals and Articles 718 



Societies and Academies : — 



The Neiv York Academy of Sciences, Section of 

 Biology: De. Gaey N. Calkins. Section of 

 Geology and Mineralogy : Alexis A. Julien. 

 Geological Conference and Students^ Cliii of 

 Sarvard University: J. M. Boutwell. The 

 Academy of Science of St. Louis : Peofessoe 

 William Teelease. University of Colorado 

 Scientific Society : De. Feancis Ramaly 718 



Discussion and Correspondence : — 



The Storage of Pamphlets : F. A. Bathee 720 



The 3Iarine Biological Laboratory at Wood' s Boll . . 721 



Geological Expedition of Dr. Becker to the Philip- 

 pines: W. F. M 722 



Conversazione of the Royal Society 723 



Scientific Notes and News 724 



University and Educational News 728 



MSS. intended or publication and books, etc., intended 

 for review should be sent to the responsible editor, Profes- 

 sor J. McKeen Cattell, Garrison-on-Hudson N. Y. 



CABL FRIED RICH GAUSS AND HIS 

 CHILDREN. 



The life of Carl Friedrich Gauss has been 

 sketched repeatedly, yet, in view of the in- 

 terest attached to every bit of new infor- 

 mation concerning men of genius, we 

 venture to touch upon a few events of his 

 later life and to speak of his descendants. 



The 16th of July, 1899, will be the 100th 

 anniversary of Gauss's graduation with the 

 degree of Doctor of Philosophy. The 50th 

 anniversary was a day of celebration at 

 Gottingen . Gauss was still in full possession 

 of his powers and was greatly admired and 

 beloved. His daughter Theresa describes 

 the memorable day in a letter, dated De- 

 cember 5, 1850, and written to her brother 

 Eugene in St. Charles, Mo. In translation 

 the passage is as follows : 



" I cannot tell you much of our quiet life ; one day 

 and one year is always very much like e ery other. 

 But they are contented daj's and years, as father even 

 now in his advanced age still possesses unimpaired 

 health and an always cheerful disposition. A year 

 and a half ago, in July, '49, he celebrated his ' 50- 

 jiihriges Doctorjubilaura' — or rather the University 

 and the city celebrated it tor him with general love 

 and sympathy. He himself was very much opposed 

 to having this day noticed, but, without his knowl- 

 edge, everything had been prepared for it. From 

 near and far the University had invited strangers ; 

 father's friends and eminent scholars came, many 

 delegations from other cities, who brought him con- 

 gratulations, honorary doctor's diplomas and three 

 new orders. From Braunschweig and Gottingen he 

 received honorary citizenship; from the King, con- 



