But, though these nations appear to have early acquired some knowledge of the art of bleaching, the progress which they made in its improvement, when compared with the advantages which some of them enjoyed, was very inconsiderable. The same practices appear to have been handed down, from one generation to another, without any material alteration. In India, the art of bleaching, as well as that of staining cloths of various colors, does not seem to be in greater perfection at present, than it is described to have been in the days of Herodotus. Even in Europe, where the arts, after they have been introduced, have generally made rapid progress, the art of bleaching advanced very slowly till towards the end of the eighteenth century, when chemistry first began to be extensively applied to the improvement of the arts.

In the middle of that century, the process occupied from six to eight months. It consisted in steeping the cloth in alkaline leys for several days, washing it clean, and spreading it on the grass for some weeks. The process of alternate steeping in a ley, and bleaching on the grass, was repeated for five or six times. The cloth was then steeped for some days in sour milk, washed clean, and once more exposed on the grass.

This tedious process was at once curtailed to that of a single day, by the application of the oxymuriatic acid, or chlorine, the properties of which were discovered by the justly celebrated Mr. Scheele. While employed in making experiments on manganese, about the year 1774, this philosopher first noticed the powers of that agent in rendering vegetable substances colorless, and stated the fact, in 1786, to M. Berthollet, more as a matter of curiosity than of use. This intelligent Frenchman lost no time in employing the properties of the curious and interesting substance, for the most important practical purposes. His application of it to the bleaching of cotton and linen cloth proving successful, he published the result of his experiments in the year 1789. The new method of bleaching was quickly and successfully introduced into the manufactories of Rouen, Valenciennes, and Courtray, and soon after into those of Manchester and Glasgow;

and it has since been generally adopted in Great Britain, Ireland, France, Germany, and the United States. The advantages which result from this rapid method of bleaching, can be best appreciated by commercial people, who experience its beneficial effects in many ways, but particularly in the quick circulation of their capitals.

Great difficulties at first impeded the progress of this improvement, arising chiefly from prejudice, as well as from the ignorance of the bleachers in the chemical processes. These obstacles, however, were soon removed, by the assistance of several eminent chemists, particularly Messrs. Watt, Henry, and Cooper.

From the volatility of the oxygen as united with the muriatic acid, when simply diffused in water, with which it has a very slight affinity; and, consequently, its unequal action on the goods immersed in it; as well as from its suffocating effects on the workmen employed, it soon became evident, that the application of it, in any extensive degree, would be impracticable if these inconveniences were not removed. Various attempts were made to effect this; and since it has been effected, several persons have put in their claims as inventors of so useful an improvement. Mr. Higgins of Dublin, and M. Berthollet, had both combined the oxymuriatic acid with potash, so early as the year 1788. The knowledge of this having been done by the latter, and of the fact that the acid was thus deprived of its offensive smell, induced the bleachers at Javelle, in France, to add a solution of caustic potash. Hence the oxymuriatic acid, combined with an alkali, is usually known by the name of the Javelle liquor.

No further improvements seem to have taken place, in the combination of this acid with any other substance than the alkalis, until the year 1798, when Mr. Charles Tennant of Glasgow, by a well-conducted series of experiments, showed that it was capable of being united with what are called the alkaline earths, such as barytes, strontitis, and lime. This discovery is of great importance, and may indeed be said to make a new era in the history of bleaching; as by means of so common and cheap a substance as lime, the full effect of the oxymu

riatic acid is communicated to the cloth, and great saving is effected by its substitution in place of an alkali.*

In the bleaching of flax and hemp, Berthollet made some experiments, which succeeded in giving to their fibres the whiteness and softness of cotton. He subjected them to the action of chlorine, which bleached them effectually; but, at the same time, it injured their fibre; and although a thread was produced of considerable tenacity, yet the shortness of the staple was such as to render the spinning a troublesome operation. It was found that this process had the remarkable property of reducing the finest flax, and the coarsest hemp, alike to one uniform fineness of fibre and color, and that even the refuse from ropewalks might thus be made into a substance valuable in the arts.t

EIGHTH WEEK-SATURDAY.

CLOTHING. THE ART OF DYEING-ITS ORIGIN AND ANCIENT HISTORY.

THE perception of color seems to be accompanied with immediate pleasure; and though the effect is probably heightened by association, it is so instantaneously produced, that we are only conscious of the pleasing emotion, and seldom think of searching beyond it for the source of our delight. Long before we are capable of analyzing our feelings, the eye is caught with the brilliancy of color and the splendor of illumination. Some, even of the lower animals, seem not to be altogether insensible to the beauties of rich and variegated tints; and man, in his rudest state, has always regarded color as a principal constituent of ornament. Nor is it only in the judgement of the infant or the savage, that colors rank high among the elements of beauty. In the most refined periods of human society, they retain their attraction; and although, to a cultivated taste, the pleasure depends * See Edinburgh Encyclopedia, article-Bleaching. + Nicholson's Journal, vol. vi.

on blending and harmonizing, rather than on brilliancy and strong contrasts, which seem to afford the first enjoyment, this refinement rather increases than diminishes their influence.

66

Among the several kinds of beauty," says Addison, "the eye takes most delight in colors. We no where meet with a more glorious or pleasing show in Nature, than what appears in the heavens at the rising and setting of the sun, which is wholly made up of those different stains of light, that show themselves in clouds of a different situation. For this reason we find the poets, who are always addressing themselves to the imagination, borrowing more of their epithets from color, than from any other topic."*

To this delight, which we derive from the perception of colors, must be referred the origin of dyeing. The savage would naturally wish to appropriate, and to have constantly in view, what afforded him so much pleasure. Vanity might induce him to adopt some colored substance as a personal ornament, or to employ it in giving beauty to the furniture of his rude dwelling. His fondness for brilliancy, or variety, would prompt him to make trial of different substances; and though many of his experiments, as they would be guided by no fixed principle, might fail, some of them would succeed, and thus gradually lead to the discovery of useful dyes. Perseverance would supply the place of knowledge, and accident would sometimes disclose, what experiment might never have found out.

These remarks may even be applied to the art, after it had attained a more advanced state, and when it might have been expected that science would have lent greater assistance to a subject so susceptible of improvement, by inductive investigation. It has often been remarked, however, and not without reason, that almost every important discovery in the arts has been the offspring of accident, and that science has done little more than suggest hints for improving what chance may have offered to human observation.

IV.

* Spectator, No. 412. 21

x.

That the art of dyeing originated before the period of authentic history, there can be no doubt. I have already observed, that it was known so far back as the time of Moses, and indeed two hundred years before his day, during the youth of Joseph; and it is worthy of remark, that even in those early days, the colors which were made use of indicated a considerable progress in the art. In India, too, the process was certainly known at a very remote period. The natural fertility of the soil of that country, and the great variety of materials which it affords for dyeing, were extremely favorable to its improvement. But religious prejudices, and the unalterable division into. castes, soon imposed restraints on ingenuity. The arts became stationary ; and it would seem, that the knowledge of dyeing cotton was as far advanced, when Alexander the Great invaded the country, as it is at present. Even at this day the Indian processes are so complicated, tedious, and imperfect, that in any other country they would be impracticable, like their mode of weaving, on account of the price of labor. European industry has far surpassed them in correctness of design, variety of shade, and facility of execution; and if, in the liveliness of two or three colors, we are inferior to them, this is solely to be ascribed to the superior quality of some of their dyes, or perhaps to the length and multiplicity of their operations.*

The Egyptians do not seem to have made any important additions to the art of dyeing; and, indeed, little could be expected from the genius or industry of a people, who were strictly prohibited, by the principles of their religion, from changing even their most indifferent customs. It appears, however, from Pliny, that they were acquainted with a mode of dyeing, very much resembling our modern calico-printing. He mentions, that the Egyptians began by painting on white cloth, with certain drugs, which, in themselves, possessed no color, but had the property of attracting or absorbing coloring matters; that these cloths were afterwards immersed in a heated

* See Berthollet.