xii PROCEEDINGS, JUNE. 
happen to be too deeply immersed. We, therefore, cannot realise the 
benefit of such papers as those of Messrs. T. B. Moore and A. Mont- 
gomery, M.A., which arouse us from our own favourite grooves, and 
recall our attention, for a time at least, to that large and important 
phase of dynamical geology known as glacial action. This phase also at 
once inevitably leads on to consideration as to its cause or cosmical 
aspect; to its effects as in its stratigraphical and physiographical aspects, 
and to the period of its manifestation as in its chronological aspect, 
Before we enter upon the question of evidence as to the occurrence of a 
former climate in Australasia sufficiently intense to be designated ‘*A 
Glacial Epoch,” we must briefly consider the character of the evidence 
by which we infer its actual occurrence. It is obvious that we cannot 
directly approach the subject of the earth’s temperature at a former 
period, for the original cooled air and the frozen water cannot be con- 
ceived to be stored up and preserved for our observation, as in the case 
of ancient forms of life preserved in the rocks, But while directly we 
ean gain no information as to temperature, we have abundant evidence 
preserved of the effects, which, according to our present knowledge, can 
only have been produced by an intensely low temperature acting upon 
watery vapours while subjected to the universal law of gravitation. It 
is therefore clear that it isin the preserved dynamic effects of moving 
masses of snow or ice and negatively in the poverty or total absence of 
life forms that we have the best, if not the only, means of inferring the 
severity of the climate of a former period. After a lengthy and detailed 
illustration of the subject in all its aspects and bearings, assisted by a 
specially executed diagram, Mr. Johnston concluded by observing that it 
was sufficient in ‘‘ respect to evidences bearing upon causes of glaciation, 
in Australia and Tasmania at least, to justify me in adopting for the 
present the following conclusions:—1l. That the Giacier Epoch of 
Australasia was probably comparatively mild in its effects, manifesting 
itself mainly by increased rainfall in lowlands, and by establishing local 
glaciers in the alpine regions of Southern Australia and Tasmania, and. 
in greatly extending the spread of the existing snowfields and glaciers 
of the New Zealand Alps. 2. That probably, in Australia, the local 
glaciers of the Alps melted before reaching the 2,000ft. levels within 
the valleys which descended continuously from the elevated snowfields ; 
and in Tasmania it is most probable that only on the western slopes of 
our western highlands was there sufficient precipitation to yield glaciers, 
any of which did not reach the sea, aud probably were melted within 
their own valleys before reaching the 1,000ft. level. 3. That the date 
at least of our most refrigerated period was probably isochronous, and 
mainly caused by the maximum cycle of eccentricity of the earth’s orbit 
with winter in aphelion, probably near to the beginning of our Neogene 
Period, say 850,000 years ago. 4. That if the latter be true, it proves 
that the astronomical theory by itself (.e., without concurrence of 
geographical conditions) would not adequately account for the ice age of 
Europe and North America, nor for the absence of marked glacial 
phenomena among the earlier tertiary deposits of Europe, at points of 
time concurring with the earlier cycles of eccentricity of the earth’s orbit 
with winter in aphelion. I do not expect that my conclusions will be 
accepted at present by many geologists who have already attained to 
crystallised views on the matter, but even these may be prepared to 
allow that, granting the premises assumed by me, my conclusions follow 
as a logical necessity.” 
Messrs. T, STEPHENS and O. H. GREENE having made some observa- 
tions on the papers read and the subjects dealt with, the usual votes of | 
thanks to the contributors were passed, and the meeting concluded. 
