57 
specific Gravity, and comparative Wear of Gold. 
removed, and the gold was poured into a mould. The button 
was externally of a dull brownish colour, and was very 
brittle. 
From the two last experiments, it may be inferred, that gold, 
when melted in close, and even in open vessels, attracts and 
combines with antimony in the state of vapour.* 
GOLD ALLOYED WITH ZINC. 
Experiment i. 
Eleven ounces one pennyweight and three grains of gold, 
23 car. 3-I grs. fine, were melted, after which, eighteen penny- 
weights and twenty-one grains of zinc were added, and, being 
quickly stirred, the whole was poured into a mould of iron. 
Upon the addition of the zinc, a bright flame immediately 
arose ; and, although as little time as possible was lost, yet, upon 
weighing the bar, it appeared, that in this short period, five 
pennyweights and twenty-one grains of zinc had been volati- 
lized, and that only thirteen pennyweights remained combined 
with the gold. 
The bar was of a pale greenish yellow, like brass, and was 
totally devoid of ductility. 
Experiment 11. 
Eighteen pennyweights and ten grains of the fine gold, were 
alloyed with 19 grains of copper, to which, when completely 
melted, 19 grains of zinc were added, and, being expeditiously 
mixed, the metal was poured into a mould. 
The external colour of the ingot was pale yellow ; it was 
* It has been proved, that arsenic will not combine readily with gold in open vessels; 
but the reverse was observed when antimony, zinc, and some other metals, were 
reduced to vapour in the vicinity of melted gold. This effect appears to depend on the 
relative affinities of the different metals with gold and with caloric. 
MDCCCIIl. I 
