INTRODUCTION OF LIGHTING BY COAL-GAS. 



" The whole of the rooms of this cotton-mill, which is, I believe, the most extensive in 

 the United Kingdom, as well as its counting-house and store-rooms, and the adjacent 

 dwelling-house of Mr. Lee, are lighted with the gas from coal. The total quantity of 

 light used during the hours of burning has been ascertained, by a comparison of shadows, 

 to be about equal to the light which 2000 mould candles of six in the pound would give ; 

 each of the candles with which the comparison was made, consuming at the rate of four- 

 tenths of an ounce (175 grains; of tallow per hour. 



" The quantity of light is necessarily liable to some variation, from the difficulty of 

 adjusting all the flames so as to be perfectly equal at all times ; but the admirable pre- 

 cision and exactness with which the business of this mill is conducted, afforded as excellent 

 an opportunity of making the comparative trials I had in view, as is perhaps likely to 

 be ever obtained in general practice ; and the experiments being made upon so large a 

 scale, and for a considerable period of time, may, I think, be assumed as a sufficiently ac- 

 curate standard for determining the advantages to be expected from the use of the gas- 

 lights under favourable circumstances. 



" It is not my intention in the present paper to enter into a particular description of 

 the apparatus employed for producing the gas ; but I may observe generally, that the 

 coal is distilled in large iron retorts, which, during the winter season, are kept con- 

 stantly at work, except during the intervals of charging ; and that the gas, as it rises from 

 them, is conveyed by iron pipes into large reservoirs, or gasometers, where it is washed 

 and purified, previous to its being conveyed through other pipes, called mains, to the 

 mills. 



" These mains branch off into a variety of ramifications (forming a total length of several 

 miles) and diminish in size, as the quantity of gas required to be passed through them be- 

 comes less. The burners, where the gas is consumed, are connected with the above mains 

 by short tubes, each of which is furnished with a cock to regulate the admission of the gas 

 to each burner, and to shut it totally off when requisite. This latter operation may like- 

 wise be instantaneously performed throughout the whole of the burners in each room, by 

 turning a cock with which each main is provided near its entrance into the room. The 

 burners are of two kinds ; the one is upon the principle of the Argand lamp, and resem- 

 bles it in appearance ; the other is a small curved tube with a conical end, having three 

 circular apertures, or perforations, of about a thirtieth of an inch in diameter ; one at the 

 point of a cone, and two lateral ones, through which the gas issues, forming three diver- 

 gent jets of flame, somewhat like a. fleur-de-lis. The ahape and general appearance of this 

 tube has procured it, among the workmen, the name of the cockspur burner. 



" The number of burners employed in all the buildings amount to 27 1 Argands and 

 633 cockspurs, each of the former giving a light equal to that of four candles of the de- 

 scription above-mentioned, and each of the latter a light equal to two and a quarter of 

 the same candles. When thus regulated, the whole of the above burners require an 

 hourly supply of 1250 cubic feet of the gas produced from cannel coal; the superior 



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