GENERAL RESEARCHES IN 1901 109 



General researches. — Of more general researches, such as are not regu- 

 larly classified by states, my list probably lacks much of completeness 

 because many of them are not reported in the ordinary way. 



Cross, Iddings, Pirsson, and Washington continued joint investigations 

 bearing directly on the systematic classification of igneous rocks. 



Van Hise continued a comprehensive study of the phenomena of 

 metamorphism. 



Merrill extended his studies of meteorites in their bearing on the 

 problems of the earth's history. Much of the early work was crude and, 

 in the light of today, unsatisfactory. With the refinements of modern 

 chemical and petrographic methods, important results may be ex- 

 pected, and detailed work on the structure and composition of these 

 interesting bodies is being carried on under the direction of the United 

 States National Museum. 



Lane is accumulating data on the grain of rocks as a function of posi- 

 tion and composition, etcetera, and is extending his theoretical re- 

 searches, especially of intrusives and of geothermal gradient. 



Keid is engaged in the study of glaciers, their structure, stratification, 

 movements, and the variations in size which they undergo. He is also 

 engaged in the study of seismologic phenomena occurring in the vicinity 

 of Baltimore, Maryland. 



Shaler continued his studies of coast lines in general, with reference 

 to recent changes in ocean level, and of the comparison of the lunar sur- 

 face with that of the earth. 



Gulliver continued the study of shoreline forms. 



Davis completed a general study of the river terraces of New England. 



Chamberlin was occupied with some of the broader and more funda- 

 mental problems of the science, including the mode of origin of the earth 

 in connection with the development of the solar system ; the origin and 

 early constitution of the atmosphere and the ocean ; the origin and 

 early states of the earth's growth, which is entirely distinct from the 

 early conception of meteoroidal aggregation ; the mode of evolution of 

 the oceanic basins and continental platforms ; the original distribution 

 and the secular change of distribution of internal heat and its function 

 in the deformation of the earth ; the autogenetic thermal conditions of 

 the earth and their relation to early life, and the secular changes of 

 land, sea, and atmosphere which constitute the basic features of histor- 

 ical geology. 



Crosby completed a study of the Neponset Valley area of the Boston 

 basin and investigated special problems in economic geology in various 

 western states and in Canada. 



Becker and Day carried forward two physical investigations bearing 



