l8o CARNKGIE INSTITUTION 



This great chemist has reached many important results, but he points 

 out that very much remains to be done, and especially recommends 

 this line of study to be taken up on an adequate scale in a geo- 

 physical laboratory. Experiments should be carried on with aqueous 

 solutions under various pressures and at various temperatures. The 

 higher temperatures should approach those of magmas, in order 

 that the relations of crystallization from magmas and crystallization 

 from water may be learned. It is held by some that there is grada- 

 tion between these. Sufl&cient has been done by various workers 

 to show that very important results can be reached by the investiga- 

 tions proposed, and a well organized, comprehensive series of ex- 

 periments is now needed. It is certain that the conditions under 

 which many of the minerals produced in nature from water solutions 

 can be produced in the laboratory. Only when this is done shall 

 we have an adequate basis upon which to judge of the kinds of min- 

 erals that are produced in nature from aqueous solutions and their 

 manner of formation. 



The study of natural underground solutions and the artificial pro- 

 duction of minerals have a most intimate relation to ore deposits. 

 Already studies along these lines have led to large advances in 

 knowledge of the development of ores. This the men engaged in 

 mining have recognized. Very recent contributions upon this sub- 

 ject have been of great practical importance in the exploration and 

 exploitation of ores. There is unanimity of opinion among geol- 

 ogists that experimental studies on underground solutions and the 

 artificial reproduction of the natural minerals will lead to correct 

 theories of ore deposition and also give results of practical value, the 

 magnitude of which cannot now be estimated. 



(3) The Deformatio7i of Rocks. — Elaborate experimental work should 

 be done upon the deformation of rocks under different conditions of 

 speed, temperature, pressure, and moisture. At the present time 

 Dr. Frank D. Adams, at Montreal, is engaged in the slow deforma- 

 tion of one rock — marble — on a small scale. Indeed, in this w^ork 

 he has the support of the Carnegie Institution ; but experiments 

 along this line need to be carried through long periods of time for 

 many kinds of rock on a much larger scale than heretofore, in order 

 that the results may be applied with safety to the observed deforma- 

 tion of the vast masses of material of the earth. But already suffi- 

 cient preliminary work has been done to show that this is a field for 

 laboratory investigations which will certainly yield important results 

 to the science of geology. 



