Dr Fyfe on ike Comparative Value of Oil and Coal Gas . IBS 
the difference in the light afforded by equal quantities of the 
gases, because, unless this be settled, it is impossible to deter- 
mine whether oil-gas can compete with coal-gas, and the conclu- 
sion at which I arrived was, that, considering the superior qua- 
lity of coal-gas, as now generally manufactured, we cannot ex- 
pect it to be above oil-gas 2 to coal-gas 1 ; and in allowing this, 
I am confident I do it every manner of justice. Unless, there- 
fore, oil-gas can be made and afforded at about double the price 
of coal-gas, it cannot come in competition with it. Though 1 
have endeavoured to fix the illuminating power of the gases in 
general, yet this is perhaps not necessary in the question with 
respect to the comparative value, as this must depend, in a great 
measure, on the situation, because the price of the raw materials, 
and other circumstances, may make the cost-price of the gases 
to differ. It is enough, therefore, if we compare the oil-gas with 
the coal-gas manufactured at the same place, or if we take the 
•coal-gas as manufactured where the materials can be got at an 
average price. 
It is unnecessary to enter into any mindte calculation with 
respect to the expence of generating coal-gas ; according to Mr 
Neilson it is manufactured at Glasgow for 4s. 6d. per 1000 
cubic feet, where, it is well known, it is made under very advan- 
tageous circumstances. By Mr Peckstone, it is estimated at 
5s. 6d. In these statements we are not informed whether the 
loss by leakage, & c. is taken into calculation ; if not, the expence 
ought to be considerably higher. At Edinburgh, coal-gas is 
manufactured for 4s. lid. per 1000 cubit feet, but making al- 
lowances for the loss, it costs 8s., which we must consider, there- 
fore, the cost-price of the gas ; and it is sold at 12s., — so that it af- 
fords a good interest on the capital, at present 8 per cent. Sup- 
pose, then, we consider the cost price of coal-gas as 8s. per 1000 
cubit feet, the question is simply this, can oil-gas, allowing it to 
have double the illuminating power, be made for about 16s. per 
1000 cubic feet, or can it even be made at 24s., and return a si- 
milar profit, for there are many who, having a high idea of its 
superior quality, will give three times the price of coal-gas. If 
it cannot be made at this, it cannot come in competition with it. 
Mr Ricardo, who was a very strong advocate in favour of oil- 
gas, has stated its cost price to be at the least 27s. per 1000 cu- 
bic feel, taking the oil at 2s. per gallon. At Hull the same 
