276 
SCIENCE. 
tion entertained in those days, the remark of the editor 
who published these papers is significant, for he says he 
“ regards the whole scheme as a bubble.” 
The next paper before me “ On the Application of the 
Gas from Coal to Economical Purposes,” by Mr. William 
Murdock — Phil. Trans., 1808, shows the question to 
have advanced to the stage when a large building had 
been illuminated by gas ; this building was the cotton 
manufactory of Phillips and Lee, of Manchester, Eng- 
land, the whole of which, together with the dwelling 
house of Mr. Lee, was lighted with gas. 
This was thought, at the time, to be a great feat, and 
shows by what slow degrees the process of gas illumina- 
tion was developed ; the idea of a central manufactory 
of gas, and that of carrying «it by pipes throughout a 
district, never entered the minds of the most advanced 
advocates of the system, but that each house or estab- 
lishment should manufacture its own gas and use it, was 
considered the perfection of gas lighting. 
Mr. Lee distilled the coal in large iron retorts, and the 
gas was conveyed into large gasometers, where it was 
washed and purified, and then conveyed to the burners. 
There were 271 burners on the principle of the Argand 
lamp, each of which gave a light, as measured by means 
of shadows, equal to four mould-candles of six to the 
pound ; and 633 burners, called cockspurs, having three 
apertures only of i-30th of an inch, and of which the 
light was equal to two and a quarter of the same candles ; 
so that the whole of the lights were equal to 2,500 
candles of that size, each of which consumed 4-ioths of 
an ounce, or 175 grains of tallow in an hour. Mr. 
Murdoch continues, “ the quantity of gas required by 
this number of burners was 1250 cubic teet in an hour. 
In some mills where the work is light, the average time 
required will be three hours, but in this manufactory the 
yearly averages is two hours a day, or 2,500 cubic feet 
of gas. This quantity of gas required the distillation 
of 7 cwt. of cannel coal.” The expense of the lights 
used in this manufactory may therefore be stated thus : 
Cost of no tons ot best Wigan cannel, at 
22s. 6d. is £12 3 
Cost of 40 tons of common coals to heat the 
retort at 10s. is 20 
^143 
Interest on capital, and wear and tear of ap- 
paratus 550 
Attendance, the same as when candles are used, 
therefore need not be stated o 
£^93 
Deduct value of 70 tons of coke ^93 
Value of 1250 ale gallons of tar not yet sold o ^93 
£600 
“ The expense of candles to give the same light would 
be, at is. per lb., nearly £ 2,000. The light is peculiarly 
soft and clear, and ot almost unvarying intensity, so as 
to be very pleasant to the workmen. It is also free from 
the danger of spark.” 
This will give an idea of the method of making com- 
parative calculations then used to determine the merits 
of gas as against the use of candlts. The editorial re- 
marks on this paper, might, if the word gas be substi- 
tuted for electricity, be taken for one of the criticisms so 
lately in fashion, and now a little obsolete. 
“ The present paper furnishes the necessary data for 
calculating the quantity of coals that would be required 
to yield a light equal to that of a given number of candles ; 
and it affords an easy means of investigating the economi- 
cal advantages of this process, which seems well adapted to 
the illumination of public buildings, large manufactories, 
and generally speaking, all establishments where a great 
number of lights are required ; but we fear the expense 
of the apparatus will always be against its introduction 
in domestic establishments on a small, or even middling 
scale.” 
The last paper I notice is “ On the Advantage of Em- 
ploying Coal-gas for Lighting Small Manufactories, and 
for Other Purposes,” by Mr. H. Cook, Philosophical 
fournal, No. 94. 
Mr. Cook in this paper drew attention to the increased 
price of tallow, on account of the “ rupture with Russia,” 
so that the advantage of using coal-gas becomes evi- 
dent. It is true, he says, that coal itself might increase 
in value, but, as he suggests, it might lead to an increased 
search and greater production. 
Mr. Murdock explains the method of making gas for 
large manufactories, and Mr. Cook in his paper describes 
his plan for making gas for dwelling houses. “ Such an 
apparatus,” he says, “ should be an 8 gallon iron pot, with 
a cover of the same metal luted on with sand. About 
20 to 25 pounds of coal are put into the pot, and dis- 
tilled, which requires the combustion of about 25 pounds 
more of coals. The quantity of gas varies with the 
quality of the coals, i,t is passed through water into the 
reservoir, which only holds about 400 gallons, but in 
general more is produced ; so that the overplus, perhaps 
200 gallons, is wasted. From the reservoir the gas is 
conveyed round the house by means of old gun barrels, 
used as tubes, and coated once a year, or seldomer, with 
the produced tar. 
“ The gas flame is found superior to that of a lamp for 
soldering with the blow-pipe. The moment the stop- 
cock is turned on, the frame is ready for use, while with 
oil or cotton wick, the workmen are forced to wait 
until the lamp is sufficiently on fire.” 
The expense of this apparatus was £ 50, but he 
thought others could be put up for ^40. 
In regard to the light produced, Mr. Cook offers the 
following facts : “The lights employed in the manufac- 
tory are 18 or 20, equal to eighteen shillings a week for 
candles, for 20 weeks, which amounts to £\"&. It used 
to cost ^30 a year for oil and cotton for the soldering 
lamps ; and the coke is certainly worth £2, 10 s. a year, so 
that, setting the tar against any little accident that may 
happen, the whole produce may be taken at £ 50. ioj. a 
year. ’ 
Supposing 50 lbs. of coal are used daily, the weekly expen- 
diture on that head will be 2 shillings, and allowing part 
of a man’s time to attend to making the gas to be worth 
5 shillings, the whole will be 7 shillings per week or ^18, 
4 shillings a year ; this however is one fourth more than it 
ought to be, because for 25 to 30 weeks the gas will not 
be required for lights. And adding to this expense £2 
a year for interest on the cost of the apparatus, there 
will remain a saving of £ 30. 6s. in the year. 
For a family using only six candles and one lamp, a 
gas apparatus would cost from £ 10 to £12, the cost ot 
which will be saved during the first year. 
The critical remark of the editor of this paper is truly 
amusing, for, by a train of reasonining, he states that he 
is compelled to oppose the introduction of gas, because 
it will raise the price of butchers' meat. The editor 
argues that if gas supersedes candles, the price of tallow 
will fall ; therefore, as the fat of animals will be reduced 
in value, butchers will have to charge a higher price for 
the leaner portion of the meat, so as to realize the value 
of the beasts. “ Therefore, as food is of more conse- 
quence than artificial light, it is rather to be depreci- 
ated.” 
A year later Mr. Cook read a second paper “ On the 
Advantages of Coal Gas Light ” (Phil. Trans. 98), which 
shows that the methods of preparing the gas was very 
imperfect, and an unpleasant oder was given off when it 
was used. In regard to this, Mr. Cook says, in reference 
to this objection that the smell occasioned by the gas is in- 
jurious to health, and that “it rather tends to preserve 
