on the Newry pitch-stone, &c. 32 5 
barrel was affixed, and luted with white lute, a glass tube, 
with a hollow ball near its junction with the mouth of the 
retort, for receiving liquids, and fitted at the other to a mer- 
curial trough, in order to collect the gases that might come 
over.* 
A considerable quantity of gas came over, in addition to 
the air of the vessel, and when the retort had acquired a red 
heat, a liquor distilled which was evidently water. 
When the heat was urged farther, another liquor made its 
appearance. It was slightly coloured and ran down, in oily 
streaks, into the receiver, where it floated on the water. 
When the distillation had ceased the apparatus was re- 
moved, all access of air excluded from the receiver, and the 
gases examined. 
They consisted of carbonic acid, which was removed by 
lime water and caustic potash ; of hydrogen, which was 
judged of by its inflammation ; and of carburetted hydrogen, 
which was tested by adding to a portion of the gas, deprived 
of carbonic acid, some oxygen gas and exploding by elec- 
tricity. Carbonic acid was thereby generated, as was proved 
by its rendering lime water turbid. 
The receiver, which had been previously weighed, was 
now examined. It had gained 7,81 grains per cent. 
The oily fluid had the smell of tobacco, exactly that of a 
tobacco-pipe long in use, and it burned with a similar flame 
to naptha : while burning it had the same smell as petroleum, 
which I had collected myself at the Pays de la Poix, near 
Clermont, in Auvergne. The water was neither acid nor 
alkaline. 
• When I ceased to look for gas, I discontinued the luting. 
