Simple Brushes (a. Round).—Of these, the most common are round paint-brushes. In arranging the fibres or hairs for paint-brushes of all kiuds, the chief object ia to place them so that their ends shall come to a central point, and in the finer kinds, especially artists' pencils, much skill is required to do this. The brush is made hy inserting a bunch of full-length bristles between two projectiog prongs on the handle, and securing them by a wrapping of twine, which ia afterwards covered with a coating of glue mixed with red-lead. Ia large paint-bruahea and paintera' duaters, the handle is aecured by driving the srnall end first into the bristlea placed in an iron cup, which holds them fast. A new hinder for bristles of paint-brushea couaists of a coutiuuoua piece of aoft inctia-rubber, attached by a cylindrical band in the bristles below the ferrule, and by connecting the perforated yoke part with the ferrule and handle. An improved method of ensuring the firm aetting of the bristlea in the handle is as followa :—The bristles are bound firmly with string in addition to cementing, a socket is turned in the periphery of the handle, to receive them, and on the periphery at the socket end, a shallow rebate ia formed, to receive the binding string. The opposite aides of the socket are then chamfered off down to near the flat bottom of it, so as to leave a shallow socket for a cylindrical hunch of bristles ; the two prongs are curved on their internal periphery. In the walla of the aoeket, are transverae saw-cuts, in order to allow of the walls yielding te the pressure of the external binding-string, which thus tightens the held on the bunch. The handle thus made is said to be cheaper, the bunch of bristles is shorter for the required elasticity, and the whole atructure ia more durable.
For makiug artists' " pencils," the delieate hairs from the fura of animals aro taken, and first washed in clean water, then soaked in warm water, dried, combed, and assorted. They are then arranged in bunches, so as to form a point, without leaving a blunt or scraggy end when the brush is wet. Thia is done by women and children, as a very delicate touch is required. The bunch ie next fastened, and drawn through the large end of a quill, till the hairs project sufficieutly beyond the other end. The quill, having been soaked beforehand ia hot water in order to enlarge it, shrinks aufficiently, on drying, to hold the brush securely. Quill& from geese, turkeya, ducks, pigeons, quails, larks, and other birda, are used. Brushes of this kind are also often mounted in metallic cups.
Flat.)—In making fiat simple brushes, sueh as whitewash bruahes, annular bands of copper or brass are prepared by apinning the metal from the flat, so that it shall have no joints. This ring or band ia of smaller diameter at the front edge than at the baek, and is strengthened in front by a lip or bead. It ia then pressed into an oval form, and the bunches are inserted ; but, before pushing the bristles quite in, a wedge of wood is introduced ia the middle and pushed in along with the bristlea, till their roots are at some depth from the back of the ring, the dovetail shape of the front part causing considerable pressure. T110 ring is then squeezed in a vice whose upper edge is grooved, and holes are made for pine or screwa to go through all. It is then warmed, and cement is run into
the hollow of the ring behind the roots of the bristles. The wooden handle is then inserted and eecured by nails or screws, or the handle is dovetailed and, after insertion, the sides of the ring are squeezed down on the sloping sides of the dovetail.
Compound Stock Brushes. (a. Set.)—In this class are included scrubbing, clothes, nail, and hat brushes, and hair brooms, dusters, &c. Such brushes are made by inserting tufts of bristles or other material into a " stock " or " head previously bored for their reception. These stocke are cut from pieces of board of the requisite thickness in such a way aa to get two out of each width. The holes are drilled through a pattern board to ensure uniformity, this being either flat or rounded according to the brush stock used ; the holes are often bored angularly to the face, or the face itself is rounded so aa to give an outward splay to the bristles or hairs. These latter are usually set in by one end, giving the full length ; but where stiffness is required, as in hair-brushes, the tufts are doubled and then cut off square and even, forming a very hard brush when doubled near the root ends. One end of the bunch, or the loop when it is doubled, dipped into hot pitch or glue, then tied, dipped again, and quickly inserted, by a twisting motion, in the hole prepared for its recep tion ; here it is securely held by the pitch on hardening. In making nail-brushea, it has been pro posed to form an oblong hole in the brush back, with the sides dovetailed or undercut so as to hold a piece of pumice similarly shaped, and placed in the hole before the back is secured to the block of the brush.
(b. Drawn.)—The distinctive feature of " drawn " brushes is that the tufts or bunches of bristles, or other materials, axe bent double, so as to form loops through which wiree are passed, for the purpose of " drawing " them into place in the holes of the stock. There ere two ordinary methods by which this is done. According to one plan, holes large enough for the bunches are made part of the way through the block, while much smaller ones are continued from the bottom of the larger ones quite through the block. The block being thus prepared, one end of the wire is passed through the loop of the first bunch, which is drawn into place ; the other end of tho wire passes out through the block, and is ready to receive the next bunch in a similar manner. This process is repeated till all the holes have been filled with hunches, when the ends of the drawing wire are secured, and the whole wire is neatly covered by a veneer back being glued or screwed on ; this strengthens and improves the brush, and prevents the wires from scratching the hand and from rusting. After this, the brush ia finished up with spokeshave and scraper, sand-papered and varnished. The " drawing " ia done by clamping the drilled stock to a table. When a row is filled, the tufts are cut off to gauge by a shear, or, when the bristles are very short, this is postponed till the brush is finished. An expert will " draw '' 500 holes per hour, but the average number does not exceed 100. For the best tooth-brushea, silver wire is used, and string ia sometimes substituted when the brush ia liable to come in contact with substances which would corrode wire.