A Dictionary of Arts, Manufactures, and Mines; containing A Clear Exposition of Their Principles and Practice
by Andrew Ure, M. D.;
F. R. S. M. G. S. Lond.: M. Acad. M. S. Philad.; S. PH. DOC. N. GERM. Ranow.; Mulh. Etc. Etc.
Illustrated with nearly fifteen hundred engravings on wood
Eleventh American, From The Last London Edition.
To which is appended, a Supplement of Recent Improvements to The Present Time.
New York: D Appleton & company, 200 Broadway. Philadelphia: George S. Appleton, 148 Chestnut St.
MDCCCXLVII
1847
[Luvusta HAT MANUFACTURE].
[Hat dyeing.] The ordinary bath for dyeing hats, employed by the London manufacturers, consists for 12 dozen, of-
144 pounds of logwood;
12 pounds of green sulphate of iron, or copperas;
7½ pounds of verdigris.
The copper is usually made of a semi-cylindrical shape, and should be surrounded with iron jacket or case, into which steam may be admitted, so as to raise the temperature of the interior bath to 190° F., but no higher, otherwise the heat is apt to affect the stiffening varnish, called the gum, with which the body of the hat has been imbued. The logwood having been introduced and digested for some time, the copperas and verdigris are added in successive quantities, and in the above proportions, along with every successive two or three dozens of hats, suspended upon the dipping machine. Each set of hats, after being exposed to the bath with occasional airings during 40 minutes, is taken off the pegs, and laid out upon the ground to be more completely blackened by the peroxidizement of the iron with the atmospheric oxygen. In 3 or 4 hours the dyeing is completed. When fully dyed, the hats are well washed in running water.
Mr. Buffum states that there are four principal objects accomplished by his patent invention for dyeing hats.
1. in the operation;
2. the production of a better color;
3. the prevention of any of the damages to which the hats are liable in the dyeing;
4. the accomplishment of the dyeing process in a much shorter time than by the usual methods, and consequently lessening the injurious effects of the dye-bath upon the texture of the hat.
Fig. 544 shows one method of constructing the apparatus. a a is a semicylindrical shaped copper vessel with flat ends, in which the dyeing process is carried on. b b b is a wheel with several circular rims mounted upon arms, which revolve upon an axle c. In the face of these rims a number of pegs or blocks are set nearly equal distances apart, upon each of which pegs or blocks it is intended to place a hat, and as the wheel revolves, to pass it into and out of the dyeing liquor in the vat of copper. This wheel may be kept revolving with a very slow motion, either by gear connecting its axle, c, with any moving power, or it may be turned round by hand, at intervals of ten minutes; whereby the hats hung upon the pegs, will be alternately immersed for the space of ten minutes in the dyeing liquor, and then for the same space exposed to the atmospheric air. In his way, the process of dyeing, it is supposed, may be greatly facilitated, and improved, as the occasional transition from the dye vat into the air, and from the air again into the bath, will enable the oxygen of the atmosphere to strike the dye mmore perfectly and expeditiously into the materials of which the hat is composed, than by a continued immersion in the bath for a much longer time.
A variation in the mode of performing this process is suggested, and the apparatus fig. 545 is proposed to be employed. a a is a square vat or vessel containing the dyeing liquor; b b is a frame or rack having a number of pegs placed in it for hanging the hats upon, which are about to be dyed, in a manner similar to the wheel above described. This frame or rack is suspended by cords from the crane, and may in that way be lowered down with the hats into the vat, or drawn up and exposed in the air; changes which be made every 10 or 20 minutes.
I have seen apparatus of this kind doing good work in the hat-dyeing manufacturies of London, that being a department of the business with which the Union has not thought it worth their while to interfere.
Mr. William Hodge's patent improvements in hat dyeing, partly founded upon an invention of Mr. Bowler, consist, first in causing every alternate frame to which the suspenders or blocks are to be attached, to slide in and out of grooves, for the purpose of more easily removing the said suspenders when required. Fig. 546 represents the improved dyeing frame, consisting of consisting of two circular rims, a a, which are connected together at top and bottom by three fixed perpendicular or the frame work b b b. Two other perpendicular frames cr similar to the former, slide in grooves, d d d d, fixed to the upper and lower rims. These grooves have anti-friction rollers in them for the purpose of makin the frames c c, to slide in and out more freely. The suspenders or substitutes for blocks, by these means, may be more easily got at by drawing out the frames c c about half way, when the suspenders, which are attached to the frames with the hats upon them may be easily reached, and either removed or altered in position and when it is done on one side, the sliding frame may be brought out on the other, and the remaining quantity of "suspenders" undergo the same operation.
The patentee remarks, that it is well known to all hat dyers, that after the hats have been in the dyeing liquor some time, they ought to be taken out and exposed to the action of the atmospheric air, when they are again immersed in the copper, that part of the hat which was uppermost in the first immersion, being placed downwards in the second. This is done for the purpose of obtaining a uniform and regular dye. The patentee's mode of carrying this operation into effect, is shown in the figure: e e are pivots for the dyeing-frame to turn upon, which is supported by the arms f, from a crane above. The whole apparatus may be raised up or lowered into the copper by means of the crane or other mechanism. When the dyeing-frame is raised out of the copper, the whole of the suspenders or blocks are reversed, by turning the apparatus over upon the pivots e e, and thus the whole surfaces of the hats are equally acted upon by the dyeing material.
It should be observed, that when the dyeing frame is raised up out of the copper, it should be tilted on one side, so as to make all the liquor run out of the hats, as also to cause the rims of the hats to hang down, and not stick to the body of the hat, or leave a bad place or uneven dye upon it. The second improvement described by the patentee, is the construction of "suspenders," to be substituted instead of the ordinary blocks
These "suspenders" are composed of thin plates of copper, bent into the required form, that is, nearly resembling that of a hat block, and made in such a manner as to be capable of contraction and expansion to suit different sized hats, and keep them distended, which may be altered by the workmen at pleasure, when it is required to place the hats upon them, or remove them therefrom. The dyeing-frame in fig. 546. is shown with only two of these "suspenders," in order to prevent confusion. One of these suspenders is represented detached at fig. 547, which exhibits a side view; and fig. 548 a front view of the same. It will be seen by reference to the figure, that the suspenders consist of two distict parts, which may be enlarged or collapsed by a variety of means, and which means may be suggested by any competent mechanic. The two parts of the suspenders are proposed to be connected together by arms g g, and at the junction of these arms a key is connected for turning them round when required. It will be seen on reference to the front view, fig. 548, that the "suspenders" or substitutes for blocks, are open at the top or crown part of the hat; this is for the purpose of allowing the dyeing liquor to penetrate.
From the mixture of copperas and verdigris employed in the hat-dye, a vast quantity of an ochreous muddy precipitate results, amounting to no less than 25 per cent. of the weight of the copperas. This iron mud forms a deposite upon the hats, which not only corrodes the fine filaments of the beaver, but causes both them and the felt stuff to turn speedily to a rusty brown. There is no process in the whole circle of our manufactures so barbarous as that of dyeing stuff hats. No ray of chemical science seems hitherto to have penetrated the dark recesses of their dye shops. Some hatters have tried to remove this corrosive brown ochre by a bath of dilute sulphuric acid, and then counteract the evil effect of the acid upon the black dye by an alkaline bath; but with a most unhappy effect, Hats so treated are most deceptious and unprofitable; as they turn of a dirty brown hue, when exposed for a few weeks to sunshine and air.
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