ORIGIN OF GOLD NUGGETS. 309 
of the liquid itself—the experiment was repeated four times. He 
points out that the conditions in Daintree’s accidental result are 
so vague and uncertain that it is impossible to credit the organic 
matter with producing the phenomena described. Neither the 
volume nor the weight of the undissolved gold was taken, hence 
he considers that the statement that after some time the fragment 
of gold had increased in size is of but little value, as it depended 
entirely upon the eye memory of the original size of the gold 
particle, and an ocular estimate of its increased dimensions. 
In his next communication, On the Formation of Gold Nuggets 
in Drift. (Read before the Wellington Philosophical Society, 
Oct. 23, 1872—Trans. N. Z. Inst., Vol. v. for 1872, pp. 377 - 383). 
Mr. Skey says, “ we cannot avoid the conclusion that gold 1s now 
being deposited and aggregated in many of our drifts, and that 
such depositions have been going on from remotest times.” He 
thinks that this gold is derived from the metal disseminated 
through slate, sandstone or schist rocks rather than from that of 
our reefs, and that we may reasonably suppose it is present as 
sulphide and is brought into solution by alkaline sulphides from 
which it is again eventually redeposited as nuggets etc., by the 
reducing effects of metallic sulphides—a mass of iron pyrites only 
two pounds in weight being sufficient to cause the deposition of a 
nugget such as the “ Welcome” weighing one hundred and eighty- 
four pounds troy. 
Sir Rod. J. Murchison (Siluria, 5th Edition, 1872, p. 465) after 
referring to Mr. A. C. Selwyn’s suggested explanation as to the 
formation of nuggets, and to Mr. Wilkinson’s experiments, says 
that he ‘ prefers to remain in his old belief, that the large nuggets 
found in the drift are simply the reliquiz of the chief masses of 
gold which once occupied the uppermost parts of the reefs, and 
that like the blocks of many an ancient conglomerate, they have 
been swept from the hilltops into adjacent valleys by former great 
rushes of water.” 
Mr. Brough Smyth, F.¢.s., in his work on The Gold Fields and 
Mineral Statistics of Victoria, 1869, p. 361, discusses the origin 
