GEOPHYSICAL LABORATORY * 



Arthur L. Day, Director. 



In view of the near approach of the tenth anniversary of the founding of 

 the Carnegie Institution of Washington, it is appropriate to cast a retro- 

 spective glance over the plans originally projected for a geophysical labora- 

 tory and the results which have been achieved under those plans, the natural 

 questions being: Has the work undertaken proved practicable? Do the 

 results satisfy the demand which was made for a geophysical laboratory? 



The first Year Book of the Institution contains two proposals for geo- 

 physical research : one by a joint committee of physicists and geologists, who 

 considered the problem in a preliminary way at the request of the Trustees ; 

 the second, a definite project for a geophysical laboratory offered by Dr. 

 G. F. Becker, of the U. S. Geological Survey. The two plans were very 

 comprehensive, but were necessarily general in character and gave considera- 

 tion to but few of the details which must be confronted in the working out 

 of so extensive a project. Neither plan was adopted at that time. 



During the following year, aided by an appropriation provided for that 

 purpose by the Trustees of the Institution, a somewhat more detailed study of 

 the project and of the geophysical problems which had been formulated by 

 different geologists and physicists was undertaken by President Van Hise, of 

 the University of Wisconsin, and by Dr. Becker. A group of leading Ameri- 

 can petrologists also devoted much thought to the general subject and to the 

 details of attack in case geophysical research should be seriously taken up. 

 The reports of these more detailed studies are contained in the second Year 

 Book of the Institution, and to these we may now profitably look back for a 

 moment if we would arrive at an opinion upon the practicability or success 

 of geophysical research under the plan then proposed. 



President Van Hise, in his examination of the field, sought specifically to 

 ascertain "the nature of the problems which geologists regard as most press 

 ing and which chemists and physicists regard as capable of being successfully 

 attacked." The questions which to him appeared to oft'er promise of success- 

 ful solution, he divides into four groups, as follows : 



1. The relations of liquid and solid rocks. 



2. Minerals and rocks from aqueous solutions. 



3. The deformation of rocks. 



4. The constants of rocks. 



In the first class he mentions the following specific problems : 



"They [the geologists] want to know the melting-points of rocks, the tem- 

 peratures at which rocks crystallize from the magma, the relative specific 

 gravities of melted and crystallized rocks, the effects of slow cooling upon 



* Situated in Washington, D. C. Grant No. 677. $54,480 for investigations and 

 maintenance during 191 1. (For previous reports see Year Books Nos. 3-9.) 

 88 



