REMOVAL OF SILVER AND GOLD BY MUNTZ METAL, 359 
Two assays were made of the scale from this, and first treated 
_ with nitric acid as usual ; unfortunately there were only sufficient 
for seventy five grains for each assay. The results obtained were : 
Silver. : Gold. 
20z. 3 dwt. 13-2 grs. 0 oz. 1 dwt. 17°8 grs. per ton. 
mee yy -.63.,, 0%, 0-8 ee ‘ 
The metal dissolved in sulphuric acid yielded— 
5 oz. 4 dwt. 9:5 grs. silver per ton. 
me 14 Is 7 
The gold is omitted on account of its containing platinum ; but 
an assay on 1000 grains dissolved in nitric acid gave 5 oz. 5 dwt. 
12 grs. of silver and 15-68 grains of gold per ton. 
Experiments with New Muntz Metal. 
Mr. Darley was also kind enough to have plates of muntz metal 
Placed for me on the piles of certain wharves, according to the 
following list, so that they might be examined from time to time, 
to ascertain whether they really do become richer in gold and 
‘ilver; each plate was divided as shown by the accompanying 
| diagram, the central stri 6” x 14” was sent to me for assay, and 
Ps 
the two other pieces 21” x 14”, were placed on a Southern and 
Northern wharf respectively, numbered and marked so that they 
can be readily identified when wanted for examination. 
Poe 
: : 
& = 1 foot 9 inches, 6 inches 1 foot 9 inches. N 
- 
SE Spaeue apap et cco a 
4 feet by 14 inches. 
Os assays of the new muntz metal, before exposure to the sea- 
§ » Were made for me in the University Laboratory by - 
peak, A.R.s.m., lecturer in Metallurgy and Demonstrator 1n 
Ch . 
mistry, now of J ohannesberg. 
