Prof. James Geikie’s Adilress. — 477 
more and more clearly developed. The conditions under which our 
old Paleolithic predecessors lived—the climatic and geographical 
changes of which they were the witnesses—are gradually being re- 
vealed with a precision that only a few years ago might well have 
seemed impossible. This of itself is extremely interesting, but I feel 
sure that I speak the conviction of many workers in this field of labour 
when I say that the clearing up of the history of Pleistocene times 
is not the only end which they have in view. One can hardly doubt 
that when the conditions of that period and the causes which gave 
rise to these have been more fully and definitely ascertained, we 
shall have advanced some way towards the better understanding of 
the climatic conditions of still earlier periods. For it cannot be 
denied that our knowledge of Paleozoic, Mesozoic, and even early 
_ Cainozoic climates is unsatisfactory. But we may look forward to 
the time when much of this uncertainty will disappear. Meteoro- 
logists are every day acquiring a clearer conception of the distribution 
of atmospheric pressure and temperature, and the causes by which 
that distribution is determined, and the day is coming when we shall 
be better able than we are now to apply this extended meteorological 
knowledge to the explanation of the climates of former periods in 
the world’s history. One of the chief factors in the present dis. 
tribution of atmospheric temperature and pressure is doubtless the 
relative position of the great land and water areas; and if this be 
true of the present, it must be true also of the past. It would 
almost seem then as if all one had to do to ascertain the climatic 
condition of any particular period was to prepare a map, depicting 
with some approach to accuracy the former relative position of land 
and sea. With such a map could our meteorologists infer what the 
climatic conditions must have been? Yes, provided we could assure 
them that in other respects the physical conditions did not differ 
from the present. Now there is no period in the past history of 
our globe the geographical conditions of which are better known 
than the Pleistocene. And yet, when we have indicated these upon a 
map, we find that they do not give the results which we might have 
expected. The climatic conditions which they seem to imply are not 
such as we know did actually obtain. It is obvious, therefore, that 
some additional and perhaps exceptional factor was at work to 
produce the recognized results. What was this disturbing element, 
and have we any evidence of its interference with the operation of 
the normal agents of climatic change in earlier periods of the 
world’s history? We all know that various answers have been 
given to such questions. Whether amongst these the correct 
solution of the enigma is to be found time will show. Meanwhile, 
as all hypothesis and theory must starve without facts to feed on, it 
behoves us as working geologists to do our best to add to the supply. 
The success with which other problems have been attacked by 
geologists forbids us to doubt that ere long we shall have done much 
to dispel some of the mystery which still envelopes the question of 
geological climates. 
