rROCEEDTNGS Or GEOLOGICAL SOCIETIES. 
143 
EoYAL Society of Edinburgh. — At a conversazione held bytbeEoyal 
Society of Edinburgh, on the 25th February last, specimens, maps, pho- 
tographic views, and sketches, illustrative of the geology* and mineralogy 
of Otago, New Zealand, were exhibited by Dr. Lauder Lindsay. They 
consisted of — 
I. A series of auriferous rocks and deposits, displaying — 1. Their general 
resemblance to those of all other auriferous countries yet known. 2. "Bed- 
rock," or metamorphic slates probably of Silurian age ; these slates pro- 
bably form the geological basis of the greater part of Otago, especially of 
central mountain-ranges, which vary in height from 5000 to 9000 feet. 
3. The general resemblance of these auriferous slates to the metamorphic 
slates of Lower Silurian age of the Scottish Grampians ; from this Dr. 
Lindsay suggests the probable difiusion of gold in Silurian slates, and 
in their derived " drifts " or alluvium in Scotland, " nuggets " having been 
already found, according to his statement, in Leadhills, Tweeddalc, Bread- 
albane, Sutherlandshire, etc. 4. " Drift," of Cainozoic age : named — 
Upper, consisting of clays, boulder-clays, and " chopped-slate " gravels ; 
Lower, characterized by lignite beds and associated strata. The gold- 
raining in Otago is mostly alluvial digging ; in the Auckland [Coromandel] 
gold-field it is mainly quartz reefing. f The chief auriferous district is the 
basin drained by the great central Lakes Hawea, AVanaka, and Wakatip, 
and the Clutha Eiver, with the feeders or tributaries. The principal works 
are in the Tuapeka and Dunstan gold-fields, and at the Lindis and Arrow 
diggings. Auriferous drifts occur also on tributaries, mostly head- waters, 
of the Mataura [Nokomai gold-field], Tokomairiro [AYoolshed], Waipori 
[Waipori], Shag and Taeri [Mount Highlay diggings], Waikouaiti, and 
other rivers and streams in diflerent parts of province, as well as on the 
coast [Moeraki beach], and in and around the capital, Duncdin [Saddle- 
hill]. Speaking generally, the greater part of Otago is auriferous, namely, 
over an area nearly equal to that of Scotland. 5. Minerals associated with 
gold, or occurring in the auriferous drift — iserine, prevalent and abundant, 
cinnabar, cassiterite, aquamarine [beryl], avanturine, etc. TJic predic- 
tion as to auriferous character of certain New Zealand rocks was made by 
Rev. W. B. Clarke, of Sydney, Government geologist of New South 
Wales, in 1851. Since then, in chronological order, we have Aorcre, Col- 
lingwood, Wangapeka, Buller Eiver, and other diggings ; operations begun 
1854-7 : Coromandel diggings ; operations begun 1852 : the discovery of 
Tuapeka, by Thomas Gabriel Eead, 4th Juno ; proclaimed a gold-field, 
July ; and first gold-escort, 12th July, 1861 : the Dunstan and Nokomai, 
proclaimed gold fields 23rd September, 18(52 : the New Zealand Gold- 
fields Act, 1858-60-62 : the Otago Gold-fields Eegulations, 7th October, 
1861 ; amended 27th June, and 21st July, 1862. In respect to the aurife- 
rous productiveness of Otago during eighteen months, from the dis- 
covery of Tuapeka to the close of 1862, the total jneld of gold was 
550,000 oz., of the value of upwards of two millions sterling ; probably in 
the following proportions: — from the Tuapeka gold-field. 360,000 oz. ; 
Waitahuna, 90,0(X) oz. ; Dunstan gold-field, 80,000 oz. ; Waipori, 7,000 oz. ; 
Woolshed, 6,0(X) oz. ; Nokomai gold-field, Highlay, Lindis, Nocraki, etc., 
7,000 : total, 550,0(X) oz. Towards the close of 1862, the mining popula- 
* Vide chapter ou " Geology of Otago," in a lecture on ' The Place and Power of 
Natural History iu Colonization, with special reference to Otago.' Pamphlet, pp. 30. 
Dunedin, January, 1862. 
t Vide papers on " Geology of the Otago Gold-fields," and on " Geology of the 
Auckland Gold-fields," read before Geological Section of British Association at Cam- 
bridge, October 5, 1862. 
