482 Transactions.— Geology. 
year was sure to bring several others across the Lindis Pass, one or other 
of which was certain to reach as far east as the Ben Ohon Range, to the 
west of Lake Pukaki, where the changing character of the river deposits 
generally arrested them. It will thus be seen that, in the face of continued 
non-success, prospecting was most persistently indulged in by numerous 
independent parties, none of which, although circumstances may have 
prevented their return, ever left without intending to return. 
The mere fact that there is much made ground (consisting of glacier 
moraines, lake and river terraces) in the district, that the river beds 
abound with quartz, or that gold in small quantities has been found, do 
not fully account for the universal belief that paying deposits of alluvial 
gold will be found. And, but for the existence amongst miners of a theory 
upon this subject, prospecting would probably have been discontinued in 
a few years after the opening of the West Coast Goldfields. 
The theory alluded to is, that as the Mackenzie Country lies to the west 
of a line drawn from the central part of the Otago Goldfields to Hokitika 
or Greymouth, the Mackenzie Country being to the west of this line, and 
therefore lying directly between the Otago and Westland Goldfields, must 
(the indications being favourable) be auriferous also; and this belief alone 
kept many in the field who would otherwise have left before they did. 
The above facts alone considered, the probable truth of the theory must 
be conceded, apart from the actual occurrence of gold in the district. But 
if a map showing the geological structure of the district be examined, the 
error to which the theory leads will be at once apparent, although there are 
important facts connected with this subject, the details of which do not 
appear on any geological map which I have seen. 
The boundary between the auriferous schists of Otago and Westland 
does, indeed, follow the water-shed of the Waitaki Valley, as shown by Dr. 
Heetor in his Geological Map of New Zealand, 1873; and, in a general 
sense, no auviferous rocks have been shown to exist east of the main water- 
shed in the provincial district of Canterbury, the non-auriferous character 
of the rocks at once accounting for the general scarcity of gold in the 
alluviums of the district. But from the plan and section which I show, it 
will Le seen how much auriferous material may be brought: down the rivers 
with but an insignificant exposure at the surface of the rocks whence the 
said materials are derived. 
The summit of Mount Cook and its eastern slopes consist of slates and 
sandstones which have not yet been proved auriferous, while to a consider- 
able altitude on its western slopes auriferous rocks are found. This same 
| arrangement with some modifieation extends throughout the first forty 
5 miles of the southern continuation of the main range, the non-auriferous 
Aree ihre o ee 
JON eren recipe e. mero a TR eee 
PUE. M 
M Aes ores TE PTR ene St RA EO S PORE e E Aire ae 
