‘ 
308 A. LIVERSIDGE. 
as to the existence of currents of electricity in the earth’s crust 
that each pyritous vein or mass with its surrounding walls and 
exciting solutions may constitute a true voltaic pair on a grand 
scale. 
A third paper by Mr. Skey is entitled, On the Mode of Pro- 
ducing Auriferous Alloys by Wet Processes. (Trans. N. Z. Inst. 
1872, p. 370). He states, amongst other matters, “that when 
chloride of gold is added to an alkaline argentiferous solution of 
this nature (silver chloride in alkaline chlorides ; silver ehloride 
in either acid or neutral solutions is not reduced by iron pyrites,) 
such mixed solution is capable of depositing the metals contained 
in it in the form of coherent alloys upon metallic sulphides.” Also 
that such alloys can be formed by voltaic action. Further “that 
as the water permeating rocks is usually alkaline it seems probable 
that native alloys of gold and silver have been deposited from 
alkaline solutions by the metallic sulphides.” 
He further remarks, that many substances will reduce gold from 
solution, but the only common ones likely to occur in the interior 
of rocks are ferrous sulphate, organic matter and the metallic 
sulphides, these also reduce metallic silver from certain of its 
solutions, but only the sulphides will reduce the two metals 
simultaneously and throw them down in coherent forms. 
Mr. Skey continued his investigations and published still further 
results in the following paper—Critical Notes upon the Alleged 
Nuclear Action of Gold upon Gold reduced from Solution by Organic 
Matter (Trans. N. Z. Inst. 1872, pp. 372-5.) In this paper Mr. 
Skey gives the results of his attempts to confirm Daintree’s and 
Wilkinson’s experiment, but, as he says, unsuccessfully; he 
accordingly describes minutely the methods which he adopted, and 
found that when a weighed piece of sheet gold was placed in a 
dilute solution of sodium chloraurate with organic matter until 
all the gold was precipitated, that the piece of gold only mereased 
in weight -0005 of a gramme, and by calculation he found that 
no more gold in proportion was deposited upon the gold plate than 
upon the sides and bottom of the glass vessel, and even the surface 
——— = 7 
