AN interesting practical application of some of the
preceding generalizations is found in an attempt
by C. E. P. Brooks ¹ to interpret post-glacial
climatic changes almost entirely in terms of crustal move-
ment. We believe that he carries the matter much too far,
but his discussion is worthy of rather full recapitulation,
not only for its theoretical value but because it gives a
good summary of post-glacial changes. His climatic table
for northwest Europe as reprinted from the annual re-
port of the Smithsonian Institution for 1917, p. 366, is
as follows:

Brooks bases his chronology largely on De Geer's
measurements of the annual layers of clay in lake

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