GOLD AND SILVHBR IN SEA-WATER. 347 
(1) 2000 ce. treated with i gram. 
lead acetate and precipitated 
by sheet zinc, yielded 0003 gr. = 0°152 er. 
(2) Filtrate treated with 1 gram. 
FeSO, and NH, yielded “0002 gr. = 0°101 gr. 
” 
” 
Total -0005 gr. =0°253 gr. 
+P 
It was found when large quantities of Coogee sea-water, ¢.9., 
forty-five litres were treated with from 1:5 to 5 grammes of ferrous 
sulphate, followed by exposure for oxidation, scorification, and 
 cupellation, that the amount of gold obtained was very much less 
in proportion than that yielded by treating one or two litres. 
Several trials were made, a larger quantity of ferrous sulphate 
would doubtless have given results similar to those obtained from 
two litres ; but I have not had time to repeat the experiments 
with large quantities of ferrous sulphate—as dealing with large 
quantities is slow and laborious with ordinary laboratory 
appliances, 
The inside of the thirty-six gallon cask which had contained 
the Coogee sea-water was scraped; but very imperfectly, about 
two ounces of scrapings obtained, they were incinerated, scorified 
and cupelled when a bead was obtained containing— 
0070 grain of silver = 5 dwt. 5°43 gr. per ton 
we, po ey By 
Only a part of the barrel was scraped, and that not deeply, but 
the above results are quite sufficient to show that the gold and 
river in sea-water are precipitated by the wood &c., hence water 
Which has been kept in wooden vessels does not yield the full 
amount of these metals, and the very small amount of silver found 
(10 Sea-water by Malaguti may have been due to his keeping the 
*a-Water in a wooden cistern, 
All my experiments were made upon sea-water collected and 
Coo n glass vessels, with the exception of the later ones on 
Water, which had been kept in the barrel. 
