Ee  —— 
— a 
Voltaic Electricity on Alcohol, &c. 321 
alcohol acted on had the specific gravity of .7928 at 66° F.* To 
produce a proper action, it was generally necessary to bring the 
foils within one-twentieth or one-thirtieth of an inch of one ano- 
ther, although sometimes the effect took place at the distance of 
one-tenth. An evolution of gas was observed to begin some- 
times almost immediately, and in other instances after the lapse 
of a minute or two, the difference in this respect, as well as in 
the requisite proximity of the foils, depending on the state of 
action of the battery, and the perfection of the various metallic 
connexions. 
When action was obtained with the foils, at the distance of 
one-tenth of an inch, it was easy to observe that the gas came 
from the negative pole, none being liberated from the positive 
pole. The action was so intense, that the liquid soon began to 
boil, and this increase of temperature materially contributes to 
the decomposition which ensues. The gas was collected some- 
times over water, and sometimes over mercury, the volatilized 
alcohol passing over at the same time, and condensing. The 
quantity of permanent gas liberated was small, from .2 to .3. of 
a cubic inch being collected in about an hour ; and there was a 
limit to the quantity collected, arising from the boiling of the 
alcohol, which left the foils partly uncovered, as well as from the 
diminished action of the battery. 
* I obtained the alcohol of this specific gravity by Mr Grauaw’s process of 
exposing: alcohol .830 to the vacuum of an air-pump with quicklime, the exposure 
being continued for some weeks, and the lime, which was common building quick- 
lime, being renewed during the process. I could not get it of lower specific gravity. 
The specific gravity of .7928 at 66° F. appears, by Mrtssnxr’s table, to correspond 
with .795 at 60° F., and with .792 at 68° F., or 20° C. In this country, absolute 
alcohol is usually reckoned to have a specific gravity of .796 at 60° F.; and on the 
Continent it is held to be of .791 at 20° C. Metssnrr, while he gives this latter as 
the specific gravity of absolute alcohol, states that the alcohol from grain, which is 
that used in this country, cannot be carried below .792 or .793.—Gmelin’s Handbuch, 
ii. 276. The difference is in all probability due to the presence of a little of the 
yolatile oil which grain and potato spirit contain. 
