the members of the field staff, the officers selected have perforce 
to be familiar with all the usual operations of the engineer and 
1 surveyor. In other words, the field staff have to be men capable, 
if need be, of producing such topographical maps as are required 
\ to lay down their geological work, and correcting or adding to 
i the topography of such maps as are available of the districts 
in which they happen to be at work. A good deal of the field 
i work is carried out by a modification of the plane-table and 
stadia methods, which by doing away with the necessity for 
chaining, is sufficiently accurate for geological requirements, 
and, what is perhaps of greater importance, is that it is expedi- 
tious. 
A topographical surveyor, Mr. H. W. B. Talbot, has now 
been included in the staff, and while adding materially to the value 
of the maps issued by the Survey, effects a considerable savin g 
in the time of the field geologists. Topographical maps do a 
great deal to promote an exact knowledge of the country, and 
in this way, apart from their other multifarious economic 
uses, are, when intelligently used, capable of being made of 
I considerable educational value. 
The work of the department in its relation to the mineral 
industry is, of course, a complicated and delicate task, affecting 
as it does such a multitude of financial and practical interests. 
Legislative provision has been made whereby the members of 
the field staff have access to mines at all reasonable times. 
Experience in most mineral fields of the globe has shown 
that many mining failures have been due rather to a want of 
knowledge of structural geology than from any lack of engineering 
training. Hence there has arisen the necessity for the detailed in- 
vestigation of mines under active development. To this end 
geological plans and sections of mines have been from time to 
time prepared. These supply records of established facts in the 
disposition and changes in the country rock, the position of the 
ore-bodies, their productiveness under various conditions, and 
thus afford data otherwise unobtainable by which operations can 
be directed into the most useful channels. Detailed surveys on 
a large scale of many ore deposits have been made in the hope 
that they might in some measure furnish a guide as to the 
general behaviour of the lodes. 
Prospecting, when it takes the form of the equipment of a 
pariy for the investigation of a particular tract of country, if it 
is to be intelligently undertaken, must be carried out in a rational 
manner. One of the first requisites for this purpose is a properly 
executed geological sketch map, which ought, amongst other 
things, to indicate those areas within which the strata possess 
economic potentialities. The knowledge thus acquired, when 
properly presented, tends to prevent the useless expenditure of 
time and money. 
