129 
Application of the Gas from Coal. 
number of working days, gives 168 tons per annum, which 
valued as before, amounts to - £188.- 
And 60 tons common coal for burning under 
the retorts, will amount to 30 
218 
Deduct 105 tons of coak at 2 6s. 8 d. - 140 
Leaving the expenditure in coal, after deduction 
of the coak, and without allowance for the 
tar, at - 78 
Adding to which the interest and wear and tear of apparatus, 
as before, the total annual cost will not be more than £650. 
whilst that of tallow, rated as before, will be £3000. 
It will readily occur, that the greater number of hours the 
gas is burnt, the greater will be its comparative economy; 
although in extending it beyond three hours, an increase of 
some parts of the apparatus would be necessary. 
If the economical comparison were made with oils, the ad- 
vantages would be less than with tallow. 
The introduction of this species of light into the establish- 
ment of Messrs. Philips and Lee, has been gradual ; begin- 
ning in the year 1 805, with two rooms of the mill, the counting- 
houses, and Mr. Lee’s dwelling-house. After which, it was 
extended through the whole manufactory, as expeditiously as 
the apparatus could be prepared. 
At first, some inconvenience was experienced from the smell 
of the unconsumed, or imperfectly purified gas, which may in 
a great measure be attributed to the introduction of successi ve 
improvements in the construction of the apparatus, as the work 
proceeded. But since its completion, and since the persons to 
mdcccviii. S 
