192 The American Geol&gist. September, 1894 
ditions have occurred, and have persisted for a considerable number of 
thousand years, which would favor glaciation on the theory of this 
paper." Dr. Becker's conclusion is thus closely harmonious with the 
presenl reviewer's estimates, as noted in the las) Mav American Gbol- 
ogist (page 364); and ii appears that he regards the causes of ice accu- 
mulation to consist more in geographic changes, as land elevation; than 
in the varying astronomic conditions. w. c. 
CORRESPONDENCE. 
A Reply to "Causes and Conditions of Glaciation."* ''The oc- 
currence of .... late Carboniferous and Permian glaciation .... is 
inconsistent with Falsan'sf and Manson's views, which have noplace foi 
general glaciation before the Pleistocene period."! 
It is true that, in the interpretations rendered in Geological and Solar 
CHmate*,there isno place for general glaciation before the Pleistocene 
period; nor has it been proved that such general glaciation has occurred. 
Widely distributed glaciations during Paleozoic time have been shown, 
but the evidence adduced is such as to wan-ant t he conclusion that such 
glaciations were local and not general. 
According to the principles and views set forth in the writer's work, 
local glaciation could have occurred at anytime during the Paleozoic 
era. provided the conditions were favorable. That local favorable con- 
ditions could have existed, is in m> way inconsistent with the view- 
therein advanced. Indeed, such local glaciation is corroborative of one 
of the prime ideas of the argument, which is. thai prior to the Quater- 
nary era surface temperatures were independent of latitude, which in- 
dependence is distinctly proved by the wide range of Paleozoic glacia- 
tions. Bad the eai'h Local glaciations been dependent upon solar heat. 
they would have been governed b\ the same laws of distribution as the 
glaciations of to-day: and had any general •"period" of glaciation 
occurred, it would have been accompanied bv arctic types of fossil life. 
such as accompanied the general Quaternary glaciation, the distinguish- 
ing tesl between local and general glaciation being fossil marine life of 
a cold temperate or arctic character. All the evidence- of early glacia- 
tion yel discovered are mechanical, i. e., boulder transportation, striae, 
etc.; and rhev occur in such varying latitudes as to distinctly prove thai 
the climates were absolutely independent of latitude. Therefore the 
Permian and Carboniferous glaciations corroborate the view set forth 
in Geological and Solar Climates, that prior to the Quaternary era surface 
temperatures were independent of latitude, being controlled by local 
conditions of elevation and conductivity of the crust. 
Again, on page 17. there occurs this objection: ••Another obstacle 
*Amerk an Geologist, July, 1894, pp. 12-20. 
fit is uauecc--.11 v t.. call attention to t lie difference between the views oi Falsan and 
those of the author, 
il.oc. cit.. pp. 10. 17, 
