450 JOURNAL OF THE WASHINGTON ACADEMY OF SCIENCES VOL. 13, No, 20 
pensation is reached. The assumption of an absolutely rigid continental 
block floating in a liquid is therefore an unsatisfactory basis for calculating 
the stresses involved. 
Taylor’s conception of the continental migration makes it mainly toward 
the equator. Wegener conceives of it as mainly westward and suggests that 
this westward movement may be due to the deflecting force of the earth’s 
rotation which would result from an equatorward movement. On the most 
favorable assumptions, however, the equatorward movement is so slow that 
this explanation is entirely inadequate. 
The hypothesis of continental migration is a serious attempt to coordinate 
and explain facts that need explanation, but the suggested mechanical 
explanations of the migration are unconvincing. ‘Till some more adequate 
explanation is offered, mathematicians and physicists are likely to doubt the 
validity of the hypothesis. (Author’s abstract). 
180TH MEETING 
The 180th meeting of the AcApEMy was held in the Assembly Hall of the 
Cosmos Club, the evening of Thursday, October 18, 1923. Dr. AEs 
HroutéKa, Curator, Division of Physical Anthropology, U. 8. National 
Museum delivered an address on Ancient man in Europe. 
The speaker, who had just returned from his third trip over the field of 
ancient man in Europe, gave a general account of his impressions, of the 
principal discoveries, and of the present status of research and opinion 
relating to Early Man. 
The strongest impressions brought back are those of the vastness of the 
European territories and deposits yielding cultural and even skeletal remains 
of geologically ancient man; of the amount of work, particulrly that of an 
archeological nature, which has already been done in this field; of the far 
greater amount of work still to be done; and of the peculiar neglect of the 
field by American scientists, with the great opportunities for American partici- 
pation now and in the future. 
As the material evidence of man of different ages together with that of the 
contemporary fauna and the geological deposits accumulates, former con- 
ceptions in all these lines are changing. There is, especially, a growing 
uncertainty as to the subdivisions and duration of the Glacial Age. The 
problems of continuous or interrupted human evolution and progress, of the 
number of human varieties and races in the past, of the fate of some of them, 
and of the derivation of others that seem to have come from elsewhere, are 
all slowly being worked out; but in some if not all these respects anthropology 
is still far from a definite solution. There are many opinions, some of them 
held very tenaciously, but they are more or less premature. Much additional 
light is needed, light to be secured through systematic and thoroughly’ 
scientific work, such as is now being carried on at a few sites, especially in 
southern France. 
What is demonstrated is that man has existed in Europe throughout or 
nearly throughout the Quaternary, and that he has in a large measure, if 
not entirely, developed there both culturally and physically. 
In conclusion, Dr. HrpurKka, who among other results of his last journey 
was honored by being the first American scientist privileged to examine the 
original remains of the Pithecanthropus, again stressed the opportunities for 
American participation in active research in this great European and Old 
