REMOVAL OF SILVER AND GOLD BY MUNTZ METAL. 357 
(h) From Neweastle and Hunter River Steamship Company’s 
upper wharf at Morpeth, N. S. Wales. Supposed to have been 
on piles four years in brackish water. Clean, 7.¢., not coated with 
green or red scale as usual, and but slightly corroded. 
Salver. Gold. 
2000 grains gave 5 ozs, 7 dwt. 10-2 grs. per ton, 
Metallic copper 62°47/. 
(1) From front of pile, No. 1 jetty, (between Nos. 4 and 5 
cranes) Bullock Island wharf, N. S. Wales. Submerged about 
twenty years in sea-water. Green, somewhat corroded, but still 
fairly thick and solid. 
Silver. Gold. 
2000 grains gave 4 ozs. 1 dwt. 16 grs. 16-5 grs. per ton. 
Metallic copper 61-6%. 
(j) From Circular Quay, Sydney, N. S. Wales. Submerged 
about forty years. The old Tank Stream, now a sewer, has its 
outfall at Circular Quay, but I do not know how near to the 
samples of sheathing examined. Much corroded, the sheets being 
eaten into large holes, 
Silver. Gold. 
4000 grs. gave 7 ov, 19 dwt. 18 grs. 6-5 gr. per ton. 
The following were treated with sulphuric acid :— 
Silver. Gold. 
2000 grs. gave 3 oz. 17 dwt. 8-4 grs. 11-90 gr. per ton. 
0, 4 oz. 15 dwt. 8-5 grs. 8°62 gr.» 
Metallic copper 61-6°/. Metallic zinc in the much corroded 
Parts = 34-687, in the thicker parts 35-49%. 
The Scale, extracted first with 500 ce. of nitric acid (1 - 3 aq.)— 
viii Gold. 
oz. dwt. 
a grains gave 4 ‘16 ll per ton. 0. a 18-5 per ton. 
me 6°12 191 4 0, a oe 
8” 7 10165 ,, 0 S48. 
150 ” RT ca es oO 7 186 ” 
br b 2. 8 189! LE 0:8 1b2 B 
; 7 10168 ,, 0:10 108) > 
Average 7 618 v8: 19 
