REMOVAL OF SILVER AND GOLD BY MUNTZ METAL. 361 
It is noticeable that the treatment with nitric acid gives a lower 
amount than that with sulphuric acid. The scale from this 
plate (110 grains) gave no gold, and under two ounces of silver 
per ton, but as the scale was largely organic matter, and copper 
oxychloride, much importance need not be attached to the per- 
centage of silver, The inner scale from this (100 grains) treated 
with sulphuric acid gave— 
Silver—9 oz. 4 dwt. 5-76 grs. per ton. (‘old contained platinum. 
No. 2. Clarence River.—Placed on No. 4 pile, Yamba wharf. 
Fixed 3rd November, 1893, in salt-water. 
No. 2a. Shoalhaven River.—Placed on back of second pile, 
eastern end of public wharf, Nowra. Fixed 31st October, 1893, 
in brackish water. The new metal gave— 
Silver. Gold. 
1000 grains gave 11 oz. 6 dwt. 17 grs. © 16 grs. per ton. 
(Dup.) iy 8 eee 16 ” 
(Trip.) hc So ee 16 ” 
No. 3. Macleay River.—Placed on front tier of piles at back 
side of pile from front of Belmore River wharf, and on second pile 
on up stream of wharf. Fixed 20th November, 1893, in brackish 
water. 
No. 3a. Newcastle.—Placed on No. 5 pile, from west end of 
Newcastle and Hunter River Steamship Company’s upper wharf, 
Morpeth, at low water spring tides. Fixed 24th November, 1893, 
in salt water. The new metal gave— 
Silver. Gold. 
1000 grains gave 10 oz. 10 dwt. 6 grs. 10 grs. per ton. 
(Dup.) i. Se oS 
(Trip.) 16 11 3 8 ,» : 
No. 4. Richmond River.—Placed on sixth pile from easte 
end of middle row of twenty ton crane wharf, south training wall 
Ballina. Fixed 1st November, 1893, in salt water. 
No. 4a. Shoalhaven River.—Placed on back of second pile, 
*astern end of public wharf, Terrara. Fixed 31st October, 1893, 
