pressure of ten atmospheres, and in all cases the gas was found to be
practically equal to the quantity mentioned, and hence of a permanent
character.

By using Keith's apparatus the results obtained were generally the
same, with the exception that an average of 0.27 per cent. of carbonic
acid gas and decided proportions of sulphureted hydrogen were found to
be present in the gas. Dr. Macadam devoted some remarks to the
consideration of the question as to how far the gas obtained from the
paraffin oil represented the light power of the oil itself, and then
he proceeded to say that, taking the crude paraffin oil at 2d. a
gallon, and with a specific gravity of 850 (water = 1,000), or 8½ lb.
to the gallon, there were 264 gallons to the ton, at a cost of £2 4s.
per ton. The sperm light from the ton of oil as gas being 3,443 lb.,
he reckoned that fully 6 lb. of sperm light were obtained from a
pennyworth of the crude oil as gas.

Then, taking the blue paraffin oil at 4d. per gallon, and there being
255 gallons to the ton, it was found that the cost of one ton was £4
5s., and as the sperm light of a ton of that oil as gas was 5,150 lb.,
it was calculated that 5 lb. of sperm light were yielded in the gas
from a pennyworth of the blue oil. The very rich character of the oil
gas rendered it unsuitable for consumption at ordinary gas jets,
though it burned readily and satisfactorily at small burners not
larger than No. 1 jets.

In practical use it would be advisable to reduce the quality by
admixture with thin and feeble gas, or to employ the oil gas simply
for enriching inferior gases derived from the more common coals. On
the question of dilution, he said that he preferred to use carbonic