128 UNIVERSITY OF MISSOURI BULLETIN 



to the elucidation of the earth's history and development. 



The primary work of the geologist is, patiently and indus- 

 triously, to accumulate as great a body of fact as possible con- 

 cerning the nature and arrangement of earth material in all 

 its phases. These are the individual units out of which the 

 geologist must build his thought-structures. The greater the 

 number and the wider the range of facts in his possession, 

 the greater will be the probability that he will build structures 

 that will satisfy his future needs. These facts must be 

 grouped — arranged according to their relation to each other 

 and their place in the thought-structures which are to be built 

 of them. Before they have been fitted together they are 

 merely accumulations. The mind of the geologist must fit 

 them together and from them build structures that may be 

 seen with one glance of the eye or one effort of the mental 

 vision. In this structure the individual facts may not be 

 consciously seen any more than are the bricks and stones in 

 a wall, but each unit fills its necessary place in the whole 

 structure. 



These thought-structures, the great conclusions built on 

 and of the facts in this way, constitute the fundamental prin- 

 ciples of the subject. These, after they are once formulated 

 and established by a strong foundation of fact, become author- 

 itative standards for the discovery and explanation of further 

 facts. Each of these principles is therefore like a kind of 

 open-work structure, into which new facts, as they are accum- 

 ulated, are fitted gradually to build up a complete structure. 

 New facts are constantly being discovered, however, that can- 

 not be accommodated in any of the existing frames or skele- 

 ton structures. In time these accumulate until enough have 

 been collected to be built into a new scheme. 



Geology, therefore, while not a science that undertakes 

 to investigate the nature and relations of fundamental facts 

 or phenomena in nature, has, nevertheless, its body of accum- 



