528 REPORT OF NATIONAL MUSEUM, 1904. 



connected for a time (1867-1870) with mining operations in Montana, 

 but his scientific field was limited wholly to Missouri and Kansas. 



At the December (1865) meeting of the Boston Society of Natural 



History, Dr. N. S. Shaler, then but twenty-four }^ears of age and a 



graduate of the Lawrence Scientific School in Cambridge, made some 



interesting remarks on the elevation of continental 



N. S. Shaler's Views 



on Continental uplift, masses. Referring to the assumptions of Charles 

 Babbage and Sir John Herschel relative to the 

 shifting of isothermal lines and consequent expansion and local uplift 

 along lines of deposition, he went on to argue that for the same reason 

 sea bottoms on which sedimentation was taking place would be areas 

 of depression, since the curving must take place in the direction of 

 greatest expansion. In like manner, uplifting would take place along 

 lines of denudation. The intermediate point between the two zones of 

 movement would naturally be the sea border, and hence here would 

 occur the fracturing of the superincumbent strata and resultant vol- 

 canic phenomena. In this way, assuming the original nuclei of the 

 continents, or points first elevated above sea level, to have been in 

 the northern portion of the sphere, he thought it probable they would 

 continue to grow by uplift southward in a succession of southwardly - 

 pointed triangles. 



Some six months later, in June, 1866, he read before the same 

 society a paper on the formation of mountain chains, which is also of 

 interest in this connection. Accepting the theory that the earth's 

 mass consists of a solid nucleus, a hardened outer crust, and an inter- 

 mediate zone of slight depth in a condition of imperfect igneous 

 fusion, he argued, as in a previous paper, that while the continental 

 folds were probably corrugations of the whole thickness of the crust 

 the mountain chains were but folds of the outer portion caused by the 

 contraction of the lower portions of this outer shell, the contraction 

 in both cases being due to loss of heat. Further, the subsidence of 

 the ocean's floors would, through producing fractures and dislocations 

 along those lines, tend to promote the formation of mountain chains 

 along and parallel with the sea borders. 



Still again, in 1868, Shaler (having in the meantime been elected 

 professor of geology in Harvard University) brought up before the 

 Society the matter of the nature of the movements involved in the 

 changes of level of shore lines, and this time with particular reference 

 to changes coincident with or subsequent to the Glacial period. He 

 showed that local phenomena of continental uplift or depression, as 

 measured by the level of the sea at the shore line, might be variously 

 modified by the position of the points of rotation, whether immedi- 

 ately at the shore line or at a greater or less distance, either seaward 

 or inland. Of greater significance, however, were his remarks rela- 

 tive to the changes in level at the time of glaciation. Referring to 



