1876.] 
Notices of Books. 
393 
Gold is, however, at present the mineral commodity most 
sought for in Otago. The following method is given for an ap- 
proximate determination of gold in pyrites : — “ Weigh a good 
average sample of the dry ore — say about 2 lbs. — and roast it 
till perfectly sweet (on a shovel over the fire will do), i.e., till no 
more smell of sulphurous or arsenious acid is perceived on 
stirring. Place the roasted mass in an iron mortar, mix it with 
so much water that it just forms a very stiff paste, and add a 
table-spoonful of quicksilver. Rub with the pestle till all the 
quicksilver has disappeared. A second similar amount of quick- 
silver is then worked through in the same way, and then hot 
water, a little soda, and about five or six table-spoonfuls of mer- 
cury are added, and the mass gently stirred for some time, to 
allow the finer particles of mercury to settle down and unite 
with the large lot at the bottom just put in. Now follows the 
careful washing away of the red oxide of iron slime, in an ena- 
melled iron dish, and ultimately the retorting — at not too strong 
heat — of the whole of the mercury colledfed. From the weight 
of the gold left behind the gold per ton can be easily calculated. 
The experiment closely imitates the process adopted on the large 
scale, and, if carefully executed, gives within 80 to over 90 per 
cent of the fire assay.” 
In an Appendix there is an account — accompanied with dia- 
grams, drawn to scale — of the German metallurgical furnace for 
burning brown coal, known as the “ Treppen-rost.” 
In speaking of the soils of the province, which are charac- 
terised as being above the average in quality, and which if care- 
fully managed will prove a source of wealth after the gold-fields 
are worked out, the authors make a very significant remark : — 
“ The gold-miners are in league with the rivers, and we may feel 
sure that before many years are passed considerable quantities 
of agricultural land will be either washed away or covered with 
‘ tailings.’ ” This is one of the many cases, not dreamt of in the 
philosophy of the Manchester school, which prove that individual 
covetousness — or, if you will, individual industry — does not, 
when left to its own guidance, invariably promote the general 
good. 
Turning from economic to historical geology, we find it men- 
tioned that in 1874 Mr. W. L. Travers brought forward conclu- 
sive proof that New Zealand has never been covered by an 
ice-sheet, or, in other words, has never experienced a glacial 
epoch. Mr. Hutton, from his own observations, also, maintains 
that neither in the pliocene nor in the pleistocene times has New 
Zealand experienced a colder climate than at present. This 
conclusion, if substantiated, is of great importance. 
The fauna of the province is remarkable for its poverty. 
Sixty-one species of land-birds in a country not over-peopled, and 
infested neither with Whitechapel bird-catchers nor with French 
sportsmen, is a very meagre list. Of these, six species belong 
K 
