128 
Mr. Murdoch’s Account of the 
He is of opinion, that the cost of attendance upon candles 
would be as much, if not more, than upon the gas apparatus ; 
so that in forming the comparison, nothing need be stated upon 
that score, on either side. 
The economical statement for one year then stands thus : 
Cost of no tons of cannel coal - £125. 
Ditto of 40 tons of common ditto - 20 
Deduct the value of 70 tons of coak - 93 
The annual expenditure in coal, after deducting 
the value of the coak, and without allowing 
any thing for the tar, is therefore - 32 
And the interest of capital, and wear and tear of 
apparatus - - - 55 o 
making the total expence of the gas apparatus, about £ 600 . 
per annum. 
That of candles, to give the same light, would be about T2000. 
For each candle consuming at the rate of 4-ioths of an ounce 
of tallow per hour, the 2500 candles burning upon an average 
of the year two hours per day, would, at one shilling per 
pound, the present price, amount to nearly the sum of money 
abovementioned. 
If the comparison were made upon an average of three 
hours per day, the advantage would be still more in favour 
of the gas light ; the interest of the capital, and wear and tear 
of the apparatus continuing nearly the same as in the former 
case ; thus, 
1250 x 3 — 3750 cubic feet of gas per day, which would 
be produced by 10^ cwt. of cannel coals ; this multiplied by the 
