204 ESTABLISHMENT OF A GEOLOGICAL SURVEY, 
tions of the Wide Bay district. In other cases, a knowledge of 
the mineral resources of a district might have an important 
influence on the direction a proposed line of railway is to take. 
Instances of this are continually arising, and it is not at all 
unlikely that the question may arise in the Brisbane district 
when the time comes to make railways to connect Brisbane 
with the towns on the east coast. I refer to the existence of 
coal a few miles to the N. of Brisbane. 
Another question, which is intimately connected with the 
geology of the country, is the question of water supply—a 
question which, at the present moment, is more important than 
any other. It is obvious that without water there caa be no 
settlement of the country; but, more than that, it is an 
undoubted fact that in all countries the sites of large towns 
have always been chosen where there has been an adequate 
water supply. Profesor Prestwich* has pointed out that in 
London those suburbs which had a good supply of water from 
springs and wells, were the first to become settled. In the case 
of the London suburbs, as it is in all other cases, this water supply 
was entirely determined by the geological nature of the land on 
which they were built. It is clear that water supply, whether 
it is in the shape of rivers or springs or lakes, must in all cases 
depend on the geological nature of the cotntry. It would be 
beyond the scope of the present paper to discuss the various 
laws which regulate the course of rivers or the flow of water 
below the ground, but it may be as well to point out upon what 
data a systematic study of the question of water, supply must 
depend. 
It will be necessary then, in the first place, to have complete 
and accurate records of the rainfall over the whole colony. 
Having obtained these records, the question then arises—What 
* Vide Address of Professor Prestwich to Geological Society of London. 
—Q. J. G. Soc., 1872, p. 53. 
