SCIENCE 



A WEEKLY JOURNAL DEVOTED TO THE ADVANCEMENT OF SCIENCE, PUBLISHING THE 



OFFICIAL NOTICES AND PROCEEDINGS OF THE AMERICAN ASSOCIATION 



FOR THE ADVANCEMENT OF SCIENCE. 



Friday, November 27, 1908 

 contents 



Uranium and Geology: Peofessoe John Jolt 737 



Report of the International Conference on 

 Electrical Units and Standards 743 



Otis Tufton Mason: AiES Hedlicka 746 



The Convocation Week Meetings 748 



The Hayden Memorial Medal 750 



Scientific Notes and News 750 



University and Educational News 754 



Discussion and Correspondence: — 



Side Issues Bearing on the Age of Niagara 

 Falls: De. J. W. Spencee. The Question 

 of Professors' Salaries: S 754 



Scientific Books: — 



Duncan's Life and Letters of Heriert Spen- 

 cer: Peofessoe R. M. Wenlet. The Devel- 

 opment of a Child: Peofessoe David R. 

 Majob. Putnam's Nautical Charts: J. F. 

 H. West Virginia Geological Survey: Peo- 

 fessoe John J. Stevenson 760 



Scientific Journals and Articles 769 



Botanical Notes: — 



Another Elementary Biology; Canadian 

 Rocky Mountain Botany; Orcutt's Amer- 

 ican Plants; A High-school Botany: Peo- 

 fessoe Chaeues E. Bessey 770 



Special Articles: — 

 Mendelian Heredity: RoswEiiH. Johnson. 

 The Otter in Massachusetts : C. E. Goedon 771 



Societies and Academies: — 



The Philosophical Society of Washington: 

 R. L. Faeis. The Elisha Mitchell Scientific 

 Society: Peofessoe Alvin S. Wheelee. 

 Section of Biology of the Pittsburg Acad- 

 emy of Science and Art: Peect E. Ray- 

 mond 775 



MSS. intended for pablicatiou and boots, etc., intended. for 

 review should be sent to the Editor of Science, Garrison-on- 

 Uudson, N. Y. 



URANIUM AND GEOLOGY— II 



RADIO-ACTIVE DEPOSITS AND THE INSTABILITY 



OF THE CRUST 



At the meeting of the British Association 

 held last year at Leicester, I read a note on 

 the thermal effects which might be ex- 

 pected to arise at the base of a sedimentary 

 accumulation of great thickness due to the 

 contained radium. 



The history of mountain-building has re- 

 peated itself many times: ages of sedi- 

 mentation, with attendant sinking of the 

 crust in the area of deposition, then up- 

 heaval, folding up of the great beds of sedi- 

 ment, and even their over-thrusting for 

 many miles. So that the mountain ranges 

 of the world are not constituted from ma- 

 terials rising from below, save in so far as 

 these may form a sustaining core, but of 

 the slowly accumulating deposits of the 

 ages preceding the upheaval. 



The thickness of collected sediments in- 

 volved in these great events is enormous, 

 and although uncertainty often attends the 

 estimation of the aggregate depths of sedi- 

 mentation, yet when we consider that un- 

 conformities between the deposits of suc- 

 ceeding eras represent the removal of vast 

 masses of sediment to fresh areas of deposi- 

 tion, and often in such a way as to lead to 

 an under-estimate of the thickness of de- 

 posit, the observations of the geologist may 

 well indicate the minor and not the major 

 limit. Witness the mighty layers of the 

 Huronian, Animikean and Keweenawan 

 ages where deposits measured in miles of 

 thickness are succeeded by unrecorded in- 

 tervals of time, in which we know with 



