Manufacture of Indian Ink.

Manufacturer and builder 4, 1870

A London journal gives the following detailed sketch of the method pursued by the Chinese in the manufacture of "Indian ink."

The materials from which the lampblack — one of the essential constituents — is procured, are placed in a furnace about a hundred feet in length, and five in breadth, along the sides and top of which it condenses. That which condenses at the extremity of the furnace is the best adapted for the manufacture of the ink, while the rest, which is deposited near the neighborhood of the combustion, is too coarse in grain to be employed for the purpose. This evidently results from two causes — one is the quality of the material, and the other the relative rapidity with which it is consumed. Having obtained the lampblack, the next step is to prepare a particular kind of paste or glue with which to form a compact and solid substance. The preparation of this glue requires a great deal of care, and is one of the most important operations connected with the whole process. The best description is made from the horns of deer. After removing the outer skin, the horns are macerated for a period of seven days in rice-water, and then subjected to a long and exhausting ebullition. It is only during the cold season of the year that this process is carried on, as hot weather would cause the fermentation of the glue and retard the operation. It mast not be imagined the lamp-black is fit for use directly it is taken out of the furnace. On the contrary, it requires to be sifted through silken bags, so that the grains may all be of the same size, or otherwise the ink would not be homogeneous. This preliminary condition being insured, a certain quantity of the glue is melted and poured over an equal quantity of the other ingredient, and the whole thoroughly kneaded and incorporated by the hands. Occasionally a small portion of Chinese varnish is added, and the mixture transferred to an iron mortar, where it is beaten up with some degree of violence. The whole of the value ef the future product depends, as is usual in all similar instances, upon the intimacy of the mixture, but, at the same time, the operation must not be protracted to too great a length. It is the duty of the manufacturer to time the process, and when, through negligence or ignoranee, the proper time has been exceeded, the error is rectified by enveloping the ink in paper, and holding it before is slow fire, which restores to it its elasticity and prevents its splitting. In spite, however, of this partial remedy, the ink so treated is never equal in quality to that which has not been subjected to such treatment.

From the mortar the mixture passes into the hand of the moulder. The moulds are formed of wood, with a cavity corresponding to the form it is desired to give to the ink. Within certain limits, the smaller the cakes the better, as there is less chance of their splitting or warping daring the time they are drying. Thus, the best cakes of Indian ink are never of a very large size. As soon as the cakes have acquired a firm and solid consistency, they are removed from the moulds and dried. Tho desiccation is effected by enveloping the ink in very fine paper, and surrounding it by cinders or powdered chalk. When the latter desiccator is used, care must be taken that it does not abstract the humidity from the cake with too great rapidity, or the latter will become brittle and lose its superior quality. The cakes, together with the absorbent envelopes, are placed in a small stove, and kept exposed to a gentle heat for several days. Some manufacturers do not take the trouble to perform this last drying process, but leave the cakes to dry by simple exposure to the air.

In order to impart an agreeable odor to the production, the Chinese add a small portion of musk and camphor, from the Isle of Borneo, two articles which are exceedingly dear in the Celestial Empire. Ordinary Chinese ink for home use is not scented in any manner whatever. The gilded mystic letters that are so attractive to young pupils and students are first formed by the action of the mould. When the cake is dry, the letters are traced over with a solution of gelatine in water, and the gold or copper is laid on with a fine brush.

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