In the common mangle, as most of our readers well know, the linen or other articles to be mangled, are wrapped round wooden rollers, which are placed upon a solid level bed or floor, and upon the rollers is placed a large oblong box, which is filled with stones, or other heavy substances, in order that they may press with great force upon the rollers, while the box is moved backwards and forwards upon them, by means of a handle attached to an upper roller or windlass to which straps from each end of the moving box are attached. By this machine, the operation of mangling is very well done, but the labour is excessive on account of the necessity of frequently arresting and changing the motion of the heavy box. In China, mangling is performed in the most perfect manner by a machine of the same kind as our common mangle, but far simpler. A concavity is formed in the floor of the apartment, of a hard and polished wood, into which is placed a roller, with the cloth intended to be mangled, around it. A heavy stone, (so shaped as to rest on either end while the operator examines his work,) is then glided on the roller, and its elevations alternately pressed by his feet, so that the article shall receive an equal pressure on every part of it.
Another extremely simple machine, delineated in the engraving on p. 127, has been applied with good effect, by Mr. Pitcher, for the purpose of mangling linen. It consists of a roller about 4 inches in diameter, and 30 inches long, with a piece of the thick woollen cloth used for ironing, firmly fixed thereon. The roller is turned round by means of a winch, and has its bearings at the ends in two stout iron plates, screwed to the sides of the table. Upon the roller rests a board, of the length and width of the table, secured to it at one end by hinges, and has at the other end a weight suspended to it, the pressure of which, upon turning the winch, winds the woollen cloth, and the damp linen articles kid upon it, so tight upon the roller, that by continuing the motion, the linen becomes as smooth as upon the common unwieldy mangle. The roller rests upon the table, and the iron plates allow it to rise and fall, according to the quantity of cloths wrapped round it. This mangle, when not in use, serves the purpose of a common table, by merely unshipping the roller; this circumstance, and the facility and cheapness with which it may be constructed by any common workman, are great recommendations to its employment by such as cannot afford, or who have not adequate occasion for, the more complex and perfect machines.
An important improvement in the construction of the common mangle, first described, was effected about thirty years ago by Mr. Baker, of Fore-street, London, by which the otherwise unwieldy heavy box was moved with great facility backwards and forwards, by a continuous motion of the handle in one direction; and by the addition of a fly wheel to equalize the motion, a great amount of muscular exertion is saved to the individual working the machine. The motion employed by Mr. Baker is highly ingenious and interesting; and although it has been superseded by others of a simpler and more efficient kind, we cannot pass it by without a brief notice of its construction. It consists of a wheel, having a series of teeth or pins on the outside of the periphery, and another series of similar teeth or pins upon the inside of the periphery. In these teeth a revolving pinion works, traversing from the inside to the outside of the wheel, or the contrary way, during the reversing of the motion, instead of confining the pinion to one course, as in working an ordinary cog wheel.
To enable the pinion to do that, a portion of the periphery of the wheel is cut away, through which the pinion passes, by rolling round from the outside into the inside, then around the latter again to the former; the axis of the pinion has therefore a range or play to the extent of the thickness of the rim of the wheel, between the inner and the outer cogs. From the foregoing, it is evident that by the continued action of the pinion, it turns the wheel round nearly a revolution one way, and then through the same space the contrary way; and as the two ends of the loaded box are attached by chains to the reciprocating wheel, it is made to traverse backward and forward. This traversing motion, by the revolution of a pinion, was subsequently improved by Mr. Elisha Peechey, and applied to a very convenient mangle, for a model of which Mr. Peechey was awarded the silver medal of the Society of Arts. This mangle had what may be called an upper and a lower rack inside a slot, which was made to traverse by the revolution of a pinion, as in Baker's patent mangle.
The pinion in this case has a stationary axis, and the bar in which the racks are formed has a pin in its upper side, which sliding between grooves in the plummer blocks, keeps it bearing against the pinion when the upper rack is operated upon; another pin is fixed on the lower side of the bar, which in like manner keeps it in contact with the pinion when the latter is operating upon the lower side, the bar containing the racks thus always accommodating itself to the continuous motion of the pinion, which thereby impels it alternately in opposite directions. A mangle of this kind, in which several important improvements have been introduced, is manufactured by Mr. Christie of Sheffield, in a style of great excellence, and at a very moderate cost. Instead of the top and bottom rack this mangle is provided with a stout metallic bar, with a row of pegs along the middle of one side of it; and parallel with the line of these pegs there is a deep projecting flange, designed to confine a pinion in its hold upon the pegs as the rack traverses backwards and forwards, by acting successively on each side of the series of pins; and the rack is so balanced by weighted levers, that as the pinion passes round the endmost peg, at either end the rack is alternately raised and depressed.