The hat being dried, its nap is raised or loosened with a wire brush or card, and sometimes it is previously poun ced or rubbed with pumice, to take off the coarser parts, and afterwards rubbed over with seal skin. The hat is now tied with a pack-thread upon its block, and is then dyed, by being first boiled with logwood, and afterwards immersed in a saline solution, consisting of a mixture of green cop peras and blue vitriol.
The dyed hats are now removed to the stiffening shop. Beer grounds are now applied on the inside of the clown, for the purpose of preventing the glue from coming through ; and when the beer grounds arc dried, glue, (gum Senegal is sometimes used,) a little thinner than that used by carpenters, is laid with a brush on the inside of the crown, and the lower surface of the brim.
The hat is now softened by exposure to steam, on the steaming bason, and is then brushed and ironed till it receives the proper gloss. It is then cut round at the brim by a knife fixed at the end of a gunge, which rests against the crown : The brim, however, is not cut entirely through, but is torn off so as to leave an edging of beaver round the external rim of the hat. The crown being tied up in gauze paper, which is neatly ironed clown, is then ready for the last opnseratio of lining and binding.
Hats are frequently made of straw, or of the chips and shavings of wood woven or plaited together, to form rib bons of narrow widths; and these are wound spirally round a block, and sewed together in a cylindrical form, so as to form the hat. The rim or border is made in a similar man ner, and sewed to the hat afterwards.
The manufacture of straw hats gives employment to vast numbers of the poor inhabitants or Hertfordshire and Bed fordshire. They select the whitest and most regular snows, and cut them exactly into lengths ; the straws are then whitened, by inclosing a great number of bundles in a large box, leaving a considerable space in the middle, into which a cup filled with sulphur is placed, and this be ing lighted, the box is shut close, and covered up with a wet blanket, to keep in the vapour of the burning sulphur, which insinuates itself through all the bundles of straw con tained in the box, and renders them whiter, and of a more delicate colour. After this preparation, the straws are split lengthwise into several segments by a wire fitted to the interior capacity of the straw, and having four, six, or eight leaves, sharp on the upper edges, and projecting ra dially from the wh es. The straws will easily split in the
proper manner when the wire is forced through them. For the convenience of holding this too], the wire is bent at right angles, about an inch below the part where the leaves project from it, and this bent part is fixed in a han dle. The slips of straw are now softened in water, and plaited together by children, with great rapidity and ex actness. The most simple plait is that of three straws; but this is only for very coarse articles, and the slips of the straws are very broad. Sometimes whole straws are employed, being first pinched flat by softening them, and drawing them through the fingers. The most esteemed plait is that of six straws, and is more or less valuable as it is finer or coarser; and after the plait is finished, it is passed several times between a pair of small wooden roll ers, to render the ribbon flat and solid. Of these ribbons the hat is formed, by winding them, in a spiral direction, round a proper shaped wooden mould or block with a little overlap, and sewing them fast together ; and when it is thus finished, the whole is passed over with a hot iron, to smooth down the seams, and the block is then taken to pieces, to withdraw it from the hat.
The Society of Arts have lately published a description of a machine for ironing down the hats upon the block. For this purpose the block is fixed upon a vertical spindle, so as to turn round horizontally ; and the pressure is given by a heated steel plate, fixed in the middle of a long lever, the fulcrum of which is supported with an universal joint, at the top of an iron stem rising up from the table upon which the machine is placed. The opposite end of the le ver has a hAndle, with which the workman presses the steel plate down upon the straw, and rubs it sidewise to smooth it clown, at the same time he turns the block and bat round upon its spindle, by means of cross arms provid ed for that purpose, to present every part to the action of the steel. An iron box is formed just over the steel plate to receive a red hot heater, and this is kept in by a lid. It is stated as a great advantage of this machine, that the pressure of the lever being considerable, the hot steel plate can be quickly passed over the straw, and does not therefore injure the colour.