WASHING COAL 1091 



Sulphate of indigo, partially saturated with potash, is used frr the blue wafers ; and 

 it is mixed with yellow, for the greens. Some recommend the sulphate to be nearly 

 neutralised with chalk, and to treat the liquor with alcohol, in order to obtain the 

 best blue dye for wafers. 



Common wafers, are, however, coloured with the substances mentioned at the be- 

 ginning of this article ; and for the cheap kinds, red lead is used instead of vermilion, 

 and turmeric instead of gamboge. 



Three new methods of manufacturing wafers were made the subject of a patent by 

 Peter Armand Do Comte cle Fontainemoreau, in April 1850; the chief feature of 

 which is a layer of metal-foil. In the first of the three forms described, the metal 

 slip or band is to be coated with the ordinary farinaceous paste used for making 

 wai'ers, for which purpose the slip is laid on one of the jaws of the ordinary iron 

 mould, then a spoonful of paste is poured on it, the mould is shut, and the paste 

 baked as usual. The metal band is lastly punched into wafers, either plain or orna- 

 mental. 



The second method is to stick these slips to paper with paste, then to dry and punch 

 them out. 



By the third plan, strips of gummed paper are fixed to the slips, and a resinous 

 cement is put on the other side. The first two methods require moistening, the third 

 heating. This contrivance is susceptible of much variety of decoration. 



WAIsWZJT HUSKS, or PEELS (Brout des noix, Fr.), are much employed by 

 the French dyers for rooting or giving dun colours. 



WAXiftTUT OIL. See OILS. 



WAXTGEES, or Japan Canes. A cane imported from China. 



WARP (Chaine, Fr. ; Kette, Anschweif, Zcttel, Werft, Qe?.) is the name of the 

 longitudinal threads or yarns, whether of cotton, linen, silk, or wool, which being de- 

 cussated at right angles by the woof or weft threads form a piece of cloth. The warp 

 yarns are parallel, and continuous from end to end of the web. See WEAVING, for a 

 description of the warping-inill. 



WASH is the fermented wort of the distiller. 



WASHING COAXi. M. Berard is the inventor of a very successful apparatus 

 for purifying small coal. He exhibited his arrangement at the Great Exhibition of 

 1851, receiving the Council medal. The decoration of the Legion of Honoxir and a 

 gold medal was also awarded to him at the Paris Exhibition in 1855. This appa- 

 ratus, to be presently described, effects, without any manual labour, the following 

 operations : 



1 st. The sorting the coal by throwing out the larger pieces. 



2nd. Breaking the coal, which is in pieces too large to be subjected to the operation 

 of washing. 



3rd. Continuous and perfect purification of the coal. 



4th. Loading the purified coal into waggons. 



5th. Loading the refuse (pyrites or schist) into waggons for removal. 



The power required for the apparatus is that of from four to five horses, and the 

 machine can operate upon from 80 to 100 tons of coal in about twelve hours, if fitted 

 up near the colliery. The expense of the operation of purifying is stated to consist 

 solely in the wages of the workmen charged to conduct the labour of tho machine. 



The following description of fhefys. 2091 and 2092, will render the arrangements 

 of M. Berard's machine readily intelligible. 



The coal is carried from the mine on a staging, for example, and the tram-waggon, B 

 (Jiff. 2091), is unloaded into a hopper, c, either by opening the bottom or by tilting it (as 

 in the position represented by the dotted lines 6), by means of a lover. It falls after- 

 wards either on to a table or a moveable grating, D, formed of frames, or of a series 

 of stages, of sloping perforated plates, which immediately sorts it into as many sizes 

 as there are perforated plates. 



This grating is suspended out of perpendicular by four chains or iron rods, c c, 

 fixed to the framework of the staging A. It is moved by means of a cam motion (an 

 arrangement of a cam and tongue mentonnet), c', and falls back by its own weight 

 against the stops, which produce concussions or vibrations favourable to the clearing 

 out of the holes and to the descent of the materials. The motion communicated to the 

 grating admits of a much less inclination being given to it than would be the case if 

 it were fixed: the sorting is effected quicker and more perfectly, besides which, the 

 differences of level which it is necessary to preserve are maintained. 



The larger pieces rejected by the first plate reach the picking-table E, where a 

 labourer picks out the largest stones and extraneous substances, as fragments of cast- 

 ings, iron, &c. 



The fragments which have passed through the upper plate, and are retained 

 by that below, descend direct to the crushers F F', situated below. Lastly, the fine 



4A2 



