the Deoxidation of Metals. 278 
I have before observed, that substances 
having ‘a powerful affinity for oxygen, will 
take it from the silver even while in a fluid 
state. ‘Thus, if charcoal be spread, for a few 
moments only, on the surface of silver that 
has absorbed oxygen, the’ whole of the oxy- 
gen will immediately be taken from it; no 
ebullition or escape of gas occurs, whether 
it be cooled gradually, as in specimen No. 4, 
or when poured into water, as in No. 5. By 
comparing these two specimens with No. 1 
and2, a very great difference will be observed, 
which is occasioned wholly by the escape of 
gas from the latter, while no such circum- 
stance attended the former. 
The bottle of gas which you will receive 
herewith, was collected in the following man- 
ner. Some silver, after cupellation, till in a 
state of perfect purity, was poured by a few 
pounds at a time into a vessel containing 
about 30 gallons of water, and an inverted 
bottle previously filled with the water, and 
with a funnel in its mouth being instantly 
placed over the silver, as it was each time 
poured into the water, the gas as it was given 
out and arose from the silver, was thus col- 
lected in the bottle until it was filled. . 
Care is necessary, that the neck of the 
bottle be kept below the surface of the water, 
VOL. 111. Mm 
