Nobody got too excited by this. In a philosophical piece, the Sydney Morning Herald (Saturday 12 December 1896, p. 15, http://trove.nla.gov.au/ndp/del/article/14079389) considered that if a gold magnet were invented, the hundred billion tons of gold that might be in the hundred billion cubic miles of the oceans might be accessible, but that, said the paper, was unlikely.… this would be in round numbers about 200 tons of gold per cubic mile, and if the volume of the ocean be considered 300,000,000 cubic miles, a total amount of gold in sea water of sixty billion tons. Yet this amount is probably insignificant in comparison with the amount of gold disseminated in crystalline and sedimentary rocks apart from gold in veins and other deposits. Experiments seem to indicate that sea water contains about the same amount of silver and gold.
(For more, see The Inquirer & Commercial News, Friday 18 February 1898, 5, http://trove.nla.gov.au/ndp/del/article/66692015 — and no, that is neither an idle sidelight, nor a mundane addendum.)A note to would-be hoodwinkers: it is these idle sidelights and mundane addenda that add sparkle to a bald and otherwise unconvincing narrative. He asked Ryan to set up the accumulator (as the device was known), to ensure that there was no trickery—another ploy of the stage magician and the con-man alike. The test went ahead in February 1897, and lo and behold! The next morning, there was gold in the mercury.