6o6 CHARLES R. VAN HISE 



as to how the resuks came about, but with no consistent attempt to 

 reduce the many observed phenomena to order under the principles 

 of physics and chemistry. The subject of metamorphism was in an 

 even worse condition. The work upon this subject was of the most 

 random character; indeed, nothing short of chaos prevailed. A 

 person who attempted to carry the multitudinous statements of facts 

 in his mind would need, more than cyclopedic powers of memory, 

 and the statements would not even have had the artificial order of an 

 encyclopedia. I became convinced that, if the treatment of meta- 

 morphism was to continue along the old lines, the subject was doomed 

 to hopeless confusion. 



With the above condition of affairs before me, I set about attempt- 

 ing to ascertain the principles which control the various kinds of 

 deformation of rock masses, and which underlay the transformation 

 of rocks. It soon became plain to me that the task was a great 

 problem in applied physics and chemistry. When this was realized, 

 it became clear that it was necessary to know the principles of physics 

 applicable to the deformation of matter and to the alteration of 

 rocks. Thus my first task was to remedy the defects of my basal 

 training by gaining a working knowledge of the well-established 

 principles of these subjects. This task I found a formidable one, 

 which occupied much of my time for several years, and which I can 

 claim to have only very imperfectly accomplished. 



In order to understand the diverse phenomena of crustal deforma- 

 tion, it was plainly necessary to know the principles of deformation 

 of small masses, such as can be handled in the laboratory. Unfor- 

 tunately it was found that this part of the subject of physics is in a 

 very imperfect condition. No systematic statement is available as 

 to the manner in which different substances behave under varying 

 conditions of stress. While studies have been made of the defor- 

 mation of iron under a moderate range of conditions, comparatively 

 little has been done concerning brittle bodies such as constitute the 

 rocks. Exact knowledge is needed as to the behavior of rocks under 

 the most extreme variations of stress, temperature, amount of water, 

 and other conditions. But while it is highly desirable to have this 

 knowledge, the geologist cannot wait until it is available. The only 

 practicable course is to study closely the phenomena of rock deforma- 



