218 Description of an Apparatus for making 



now engaged here on his own account, and has made con- 

 siderable improvements in their construction. 



I remain, dear sir, your most obedient servant, 



Asil WORTH CLEGG. 



■ Manchester, May 18, 1808. 



To C. Taylor, M.D. Sec. 



SIR, 



Your esteemed favour I have received, and, according to 

 your request, have sent you a fuller explanation of the ga- 

 zometer and lamp, accompanied with further drawings. 



A gazometer, containing seven hundred cubical feet of 

 gas, weighs about twenty hundred weight, and costs about 

 two pounds ten shillings the hundred weight. 



The whole of an apparatus complete, capable of support* 

 ing forty lamps for four hours, each lamp affording light 

 equal to ten candles of eight in the pound, will cost about 

 two hundred and fifty pounds. Each lamp consumes six 

 cubical feet of gas per hour. I am happy to find that the 

 Society have honoured my communications with their at- 

 tention, and T remain, with great respect, 



Sir, your most obedient servant, 



S. Clegg. 



Manchester, Aug. 12, 1808. 



To C. Taylor, M.D. Sec. 



Reference to Mr. S. Clegg's improved Apparatus for ex- 

 tracting Carbonated Hydrogen Gas from Pit Coal. See 

 Plate V. Figs, 1, 2, 3, 4, 5, and 6, 



In fig. 1, A shows the cast iron retort, into which are 

 put the coals intended to be decomposed by means of a fire 

 underneath it, the heat of which surrounds every part of it, 

 excepting the mouth or part by which the coals are intro- 

 duced. The lid or iron plate B> which covers the mouth 

 of the retort, is ground on air tight, and fastened by means 

 of a screw in the centre ; C is a shield or saddle of cast iron, 

 to preserve the retort from being injured by the intensity of 

 the fire underneath it, and to cause it to be heated more uni- 

 formly. DDD represents the cast iron pipe which con- 

 veys 



