The annual consumption of rags in this country alone far exceeds 120,000 tons, three-fourths of which are imported, Italy and Germany furnishing the principal supplies. That the condition in which the rags are imported furnishes any criterion of the national habits of the people from which they came, as has been frequently asserted, however plausible in theory, must, at least, be received with caution. But that is by no means important. The specimen of printing paper, No. 21, was manufactured from a selection far from cleanly; in fact, there was not a white rag employed, while even fustians, corduroy, and coloured rags formed a considerable proportion.
In considering the various processes or stages of the manufacture of paper, we have first to notice that, of carefully sorting and cutting the rags into small pieces, which is done by women; each woman standing at a table frame, the upper surface of which consists of very coarse wire-cloth; a large knife being fixed in the centre of the table, nearly in a vertical position. The woman stands so as to have the back of the blade opposite to her, while at her right hand on the floor is a large wooden box, with several divisions. Her business consists in examining the rags, opening the seams, removing dirt, pins, needles, and buttons, of endless variety, which would be liable to injure the machinery, or damage the quality of the paper. She then cuts the rags into small pieces, not exceeding four inches square, by drawing them sharply across the edge of the knife, at the same time keeping each quality distinct, in the several divisions of the box placed on her right hand. During this process, much of the dirt, sand, and so forth, passes through the wire-cloth into a drawer underneath, which is occasionally cleaned out. After this, the rags are removed to what is called the dusting machine, which is a large cylindrical frame, covered with similar coarse iron wire-cloth, and having a powerful revolving shaft extending through the interior, with a number of spokes fixed transversely, nearly long enough to touch the cage. By means of this contrivance, the machine being fixed upon an incline of some inches to the foot, the rags, which are put in at the top, have any remaining particles of dust that may still adhere to them effectually beaten out, by the time they reach the bottom.
Some objection, however, may be made to this method, which has a tendency to blow away at the same time a considerable portion of fibre set loose in cutting the rags, along with the dust. To avoid this waste, an invention has recently been brought out by a son of the late eminent Mr. Fourdrinier, which he terms his “Patent Accelerator.” The process adopted is simply that of placing the rags in their dirty state in water, and employing that as a medium for carrying off the dust and dirt, in preference to air. The invention has not yet been very extensively used, and consequently I am not in a position to say much as to its merits.
The rags being thus far cleansed, have next to be boiled in an alkaline lye or solution, made more or less strong, as the rags are more or less coloured, the object being to get rid of the remaining dirt and some of the colouring matter. The proportion is from four to ten pounds of carbonate of soda with one-third of quick lime to the hundred weight of material. In this the rags are boiled for several hours, according to their quality.
The mode now adopted as the most recent improvement is that of placing the rags in large cylinders, which are constantly, though slowly, revolving, thus causing the rags to be as frequently turned over, and into which a jet of steam is cast with a pressure of something near 30 lbs. to the square inch.
RAG ENGINE
After this process of cleansing, the rags are considered in a fit state to be torn or macerated until they become reduced to pulp, which was accomplished some five and thirty or forty years since, by setting them to heat and ferment for many days in close vessels, whereby in reality they underwent a species of putrefaction. Another method subsequently employed was that of beating them by means of stamping rods, shod with iron, working in strong oak or stone mortars, and moved by water-wheel machinery. So rude and ineffective however was this apparatus, that no fewer than forty pairs of stamps were required to operate a night and a day in preparing one hundred weight of material. At the present time, the average weekly consumption of rags, at many paper mills, exceeds even 30 tons. The cylinder or engine mode of comminuting rags into paper pulp appears to have been invented in Holland, about the middle of the last century, but received very little attention here for some years afterwards. The accompanying drawing will serve to convey some idea of the wonderful rapidity with which the work is at present accomplished. No less than twelve tons per week can now be prepared by means of this simple contrivance. The horizontal section represents an oblong cistern, of cast iron, or wood lined with lead, into which the rags, with a sufficient quantity of water, are received. It is divided by a partition, as shown (A), to regulate the course of the stuff. The spindle upon which each cylinder (C) moves, extending across the engine, and being put in motion by a band wheel or pinion at the point (B). One cylinder, is made to traverse at a much swifter rate than the other, in order that the rags may be the more effectually triturated. The cylinders (C), as shown in the vertical section, are furnished with numerous cutters, running parallel to the axis, and again beneath them similar cutters are mounted (D) somewhat obliquely, against which, when in motion, the rags are drawn by the rapid rotation of the cylinders, and thus reduced to the smallest filaments requisite, sometimes not exceeding the sixteenth of an inch in length; the distance between the fixed and moveable blades being capable of any adjustment, simply by elevating or depressing the bearings upon which the necks of the shaft are supported. When in operation, it is of course necessary to enclose the cylinders in a case, as shown (E), otherwise a large proportion of the rags would inevitably be thrown out of the engine. I should mention, that the rags are first worked coarsely, with a stream of water running through the engine, which tends effectually to wash them, as also to open their fibres; and in order to carry off the dirty water, what is termed a washing drum is usually employed, consisting simply of a framework covered with very fine wire-gauze, in the interior of which, connected with the shaft or spindle, which is hollow, are two suction tubes, and by this means, on the principle of a syphon, the dirty water constantly flows away through a larger tube running down outside, which is connected with that in the centre, without carrying away any of the fibre.
After this, the mass is placed in another engine, where, if necessary, it is bleached by an admixture of chloride of lime, which is retained in the engine until its action becomes apparent. The pulp is then let down into large slate cisterns to steep, prior to being reduced to a suitable consistency by the beating engine, as already described. The rolls or cylinders, however, of the beating engine are always made to rotate much faster than when employed in washing or bleaching, revolving probably from 120 to 150 times per minute, and thus, supposing the cylinders to contain 48 teeth each, passing over eight others, as shown in the drawing, effecting no fewer than 103,680 cuts in that short period. From this the great advantage of the modern engine over the old fashioned mortar machine, in turning out a quantity of paper pulp, will be at once apparent.
The operation of paper making, after the rags or materials to be used have been thus reduced and prepared, may be divided into two kinds; that which is carried on in hand-mills, where the formation of the sheet is performed by manual labour; and that which is carried on in machine-mills, where the paper is produced upon the machine wire-cloth in one continuous web.