406 T. W. VAUGHAN RESEAKCHES ON SEDIMENTATION 



Eesearches such as those enumerated, and the number might be greatly 

 increased, have given insight into some of the factors and principles in- 

 volved in the origin and subsequent changes of sedimentary rocks. One 

 important result of these investigations is to make clear the complexity 

 of the phenomena; another important result is to make it clear that an 

 adequate basis for interpreting sediments will not be established until all 

 the needed lines of research have been brought to bear in proper coordi- 

 nation on the different classes of sedimentary deposits. 



Suggestions as to the Means of fukthering Researches on 



Sedimentation 



The discussion so far has presented the object of researches on sedi- 

 mentation in their geologic bearing; it has indicated the range of phe- 

 nomena that should be covered ; and it has pointed out that certain valu- 

 able researches have not been completely satisfying in their results. An 

 attempt will now be made to bring forward some suggestions for increas- 

 ing activity in this field of scientific endeavor and for providing addi- 

 tional agencies. The factors entering into the origin and the deposition 

 of sediments and into the changes that take place in them after their 

 deposition are so diverse and are so widely distributed that it is imprac- 

 ticable for any one man, any small group of men, or any organization of 

 moderate size, especially one whose activities are areally limited, to cover 

 the field. All possible activity needs to be encouraged and all possible 

 agencies should be utilized. 



According to the opportunities of individuals and organizations, three 

 categories of researches may be recognized, as follows: (1) Researches 

 on specific phenomena; for instance, Grilbert's "Transportation of debris 

 by running water" and Harder's "Iron-depositing bacteria and their geo- 

 logic relations"; (2) researches covering particular areas, such as Thou- 

 let's study of the deposits in the Gulf of Lyons, Kindle's studies of the 

 Great Lakes, and the work being done in San Francisco Bay by the geol- 

 ogists of the University of California; (3) complex investigations, re- 

 quiring the cooperative and coordinate researches of physicists, analytical 

 chemists, physical chemists, and biologists (including bacteriologists). 

 There is no good instance of such an investigation, for there has been no 

 institution established for conducting such researches. I attempted a 

 piece of work of this kind in the study of the marine bottom deposits of 

 Florida and the Bahamas, but, although valuable data were procured, the 

 results obtained are inadequate. Sir John Murray had a similar ideal in 

 mind in investigations conducted at the Granton Marine Laboratory, and 



