As a rule, plate singeing is preferred for thick, heavy fabrics, and gas singeing for light cloths, such as muslins, jaconets, &o. The pieces may run at the rate of 150 to 200 single width pieces of 25 yds. each per hour, constant attention being requisite to regulate the speed for the different ties of cloth, to prevent unequal, defective, or excessive singeing, and to guard against any accidents arising from fire. A very effective apparatus, in place of the water trough already mentioned for extinguishing sparks, is the small box fitted up in tbe intexior with a few 'rollers and a perforated steam pipe. Through this box filled with steam, the cloth from the singe plates passes.
After working some time, a fine downy dust collects about the singeing machine and not un frequently becomes ignited ; hence every caution is necessary. The singeing-house should be frequently swept, and it is always safer to have the whole building fireproof and apart from the rest of the works.
With regard to the consumption of coal in singeing, O'Neill states ss the result of his experience with a double plate stove, heated by one fire and return flue, stove in good condition, and usiug ordinary engine coal, that 1 lb. of coal will singe fairly well 80 yds. calico ;L.-yd. wide, two pieces going over at once. Schultz reports from Weaserling that 11b. coal singes about 65 yds. calico, with iron plate and once singed. Experiments conducted at Messrs. Salle Schwabe's works near Blan chester, by Mr. Hill, with the coke flame and double copper plate, gave the following result : 1 owt. 3 qrs. 9 lb. coal 1 " .. used per 1000 pcs. 25 yds. each.
1 3 0 cokef This is equal to 1 lb. of coke and coal for 62 yds. calico, the singe being good and complete. O'Neill gives the following data for the consumption of gas in Tulpin's machine : Works near Manchester .. 25,000 yds. f-yd. wide, singed with 1330 cub. ft. gas.
Meyer (Steinbach Koechlin's) 25,000 1075 ,, Schultz (Wesserling) .. 25,000 7) 1192 .newsoulug bout con oi corm pews iu,uuu cub. ft. of gas, these figures show that 1 lb. of coal in the form of gas sioges from 69 to 86 yds. of calico.
Before going into the details of the processes involved in bleaching proper, it will be well to describe the bleach house and the machinery in use at the present time. Figs. 341, 342, and 343, show the ground-plan and elevations of a modern bleach-house for calico-printing in Lancashire, viz. that of Messrs. Alex. Drew and Sons. All the machines are
driven by belting from an overhead shaft, by which means the noise from under ground gearing, as used in many works, is reduced to a minimum, and the shaft ing is preserved from the corrosive action of weak acids, &c., splashing from the machines. This is probably the only bleach-house in Britain where the ma chines are driven in this manner.
Another modern method adopted in establishments of good standing is to have each machine driven by a separate engine with double cylinders. It may be remarked in passing, that this plan of dispensing with shafting and gearing, and planting engines of this class to drive each separate machine, is carried out in all the departments of the bleach ing and finishing processes. In this case, where steam pipes take the place of shafting, there is not the same liability of the whole works being suddenly brought to a standstill, as sometimes occurs when a main shaft breaks ; and, besidos the fact that each individual machine may be driven at the most suitable or productive speed, the occur rence of accidents to workmen engaged in oiling shafting is avoided, and it is reckoned that this method of distributing the motive power is ultimately more eco nomical.
In Fig. 342, B B B represent eight Barlow's kiers or boilers, which are worked in pairs. Behind these, running along the wall, are the steam, liquor, and water pipes, connected with the kiers, whioll stand surrounded by a high wooden nualt,re 61.1, Cmay cu,ucca Dv Imo Luvuu.
of each kier, and to the various steam taps, &o. The boilers themselves are made of malleable iron plates, riveted together, and are supported upon cast-iron columns, sufficient in height to elevate the boilers from the ground and thus prevent corrosion. Above each boiler, is a winch R, with wooden spars, by which the pieces are drawn in filling the kicrs ; other winches are placed in suitable parts of the bleaching-house for piling the pieces on the floor. Here and there on the beams overhead, are fixed numerous so-called " pot-eyes " ; these are rings about 4 in. in diameter, made of glass or glazed earthenware, fixed in wooden spars or otherwise secured, for the purpose of guiding the cloth, and preventing its coming into contact with iron pillars, &c. Close to the wooden stage surrounding the kiers, the various limeing, washing, souring., and chemicking machines are arranged, forming a single row, in the order in which they are required.