DIRECTIONS TO WORKMEN
ATTENDING
THE GAS-LIGHT APPARATUS[43].
[43] Copied from a printed direction drawn up by Mr. Clegg, for the use of workmen.
Particular care must be taken to make the joints of the mouth-pieces of the retorts perfectly air tight, which may be done in the following manner:—Take some common clay, dry, pulverize, and sift it, then add as much water as will make it into the consistency of treacle; make the mouth-piece and the lid of the retort clean, lay this luting thinly over the turned part of the lid, press the lid so luted gently to the mouth-piece, and then secure it moderately, by means of the iron wedge: if the workman observes this rule, he will never fail to make good joints; but if, on the other hand, the operator is careless and neglects to remove the old luting, &c. from the turned or smooth part of the mouth of the retort, and thereby cause a bad joint, the consequence will be the loss of a considerable quantity of gas, and a very disagreeable smell and smoke.
The bridge or row of bricks of the flue C, of the retorts, should never be made hotter than a bright red, which may be regulated by the door of the ash-pit being kept close shut when the fire is getting too hot. If the operator neglects this, and suffers the fire-bricks to arrive at a bright white heat the retorts will soon be destroyed, and bad gas be produced.
The gasometer should be well examined, at least once a week, to see if it leaks, by the following method, viz. Let the main stop-cock be shut, then make a mark on the gasometer at the water’s edge when it is full or nearly of gas, there being no gas coming from the retorts at the time, and if the mark sinks in the water, the gasometer leaks; to find out the place, walk slowly round it, and you may perceive the leak by the smell, apply a lighted candle to the part suspected, and if there be gas issuing from it, it will take fire, and perhaps appear like a small blue flame—blow it out, and mark the place: thus proceed round the gasometer till you have found all the places; if you perceive a smell, and yet cannot produce a flame in the part suspected, take a brush with a little thin white-lead paint, and lay it on the part where you think the leak is, and, if it be there, the gas which escapes from the leak, will immediately turn the paint brown. After the sides of the gasometer have been well examined, and secured by dipping a piece of cloth about the size of a shilling, into some melted pitch, tempered with a little bees-wax and tar, apply the cloth whilst hot to the place with the end of your finger, rubbing it till it is quite cold; next examine the top of the gasometer in the same manner,—when it is about two feet high in the cistern, it will then be better to get at. The water in the cistern should always be kept within 3 or four inches of the top, if suffered to sink much lower without replenishing, the gas will not pass through a sufficient quantity of water, and oily particles will be apt to condense in the pipes, to their great detriment.
The only thing to be observed in the place lighted is, that the lamps and pipes are not suffered to be touched on any pretence whatever, but by the person entrusted with their care. When a lamp is not wanted, it must be completely shut off from the pipe which supplies it, by a stop-cock provided for the purpose, and not opened again but when a flame is held over it; not a lighted candle, as the tallow is liable to drop into the lamps; lighted paper is better.