It can now be manufactured, at a profit, for not over one one-thousandth of what it cost in those days, not allowing, either, for the difference in value of money between then and now. And yet this famous dye, which was so highly esteemed and of which so much has been written, is so inferior in color and tone to several of the modern dyestuffs that it probably would not pay to put it on the market. Dr. Friedlaender’s samples were, indeed, fast to both light and washing, but their color showed dull and, to modern eyes, distinctly uninteresting shades of violet. And there are already on the market several violet, red and blue dyes of the same general class—the indigo or vat dyes—which are quite as fast to light and washing, and far superior in beauty and brilliancy of shade.
It is only proper, however, to state that Dr. Friedlaender’s investigation did not completely clear up the subject, though there is no question but that he really discovered the true Tyrian purple; and the color of the specimens dyed and exhibited by him corresponded very closely to some still surviving from antiquity.
Among the fine collections of textiles from the Egyptian tombs that are in the Metropolitan Museum of Art in New York City, are some excellent examples of Tyrian purple. These are what the Greeks used to call “di-bapha,” or double dyed—i.e., dyed very deep, full shades of dark purple. While a wonderful example of the lighter, violet, shades of the same dye can be seen in a famous manuscript, known as “The Golden Gospels,” now in Mr. J. Pierpont Morgan’s collection in the same city, but which was given about 1520, by Pope Leo X to King Henry VIII. This was written, in golden characters, upon vellum dyed with Tyrian purple, and the shades of the latter correspond quite closely with the violet of the artificial brom-indigo compound.
On the other hand there is evidence to show that the ancients were also able to obtain, with the same Tyrian purple dye, perhaps from the shellfishpurpura lapillus, fast and brilliant shades of scarlet, as well as these rather dull tones of violet and purple. In the days of the Roman Empire, as above mentioned, the use of “purple” garments was denied to all but the imperial family; but later, after the rise of the Christian Church, the ecclesiastics gained sufficient power to obtain this privilege for themselves. And to this day the cardinals of the Roman Catholic Church are called “porporati” on account of the “purple” or, as we would say, scarlet, color of their characteristic robes. So, whenever we see the red robes of a high dignitary of the church we are probably looking at one of the tints of the real old Tyrian purple, although the art of actually producing it has long since been lost; and, if rediscovered, would probably be of as little practical value as Dr. Friedlaender’s remarkable investigation.
THE DYES OF OUR ANCESTORS
Between the days of the ancient Greeks and Romans, and the discovery of the first aniline dye in 1856, many and important additions were made to the list of available dyestuffs, some of which have continued in use, for special purposes, up to the present day.
Indian Dyes.—The opening of trade to the Far East, due to the discovery of the sea route round the Cape of Good Hope, brought to Europe the free use of some of the Indian dyestuffs. Indigo, for instance, was introduced for the first time in considerable quantities, and, after much opposition, completely took the place of the much inferior native dyestuff, woad.
For yellow, the old saffron dye was superseded by the more powerful, but still rather fugitive, turmeric, or Indian saffron. This came from the root of the curcuma tinctoria, a plant freely grown to this day in both India and China. The safflower was also imported from India; this is a kind of thistle,carthamus tinctorum, the dried heads of flowers of which were largely used for dyeing pretty shades of pink upon cotton,directly—that is, without any mordanting process. This color, too, is comparatively fugitive to light, and has almost disappeared from sight.
Of more importance were the so-called red woods, which came partly from India and partly from the east and west coasts of Africa; and of which the most important are the sandal wood, bar wood, and cam wood. The wood of each of these trees probably contains the same coloring matter. The color is not very easy to extract, but when used with mordants of chromium, aluminium, or tin salts, it dyes wool various shades of red and reddish-brown. These colors are very fast to milling—in other words to the action of alkalies when the wool is finished in the manufacture of broadcloth; but they are not particularly fast to light, and for this reason, as well as because of their greater expense, they have been for the most part abandoned.
From India, too, were introduced the well-known brown dyes known as cutch (catechu) and gambier. These come to the market in the form of dark colored pastes, formed by evaporating infusions of leaves, seed pods, nuts, and sometimes the wood of various species of acacia and areca trees. They contain large amounts of a peculiar variety of the substance known as tannin or tannic acid, which is widely distributed among many plants, and which is very useful in dyeing, as will be described later. The brown coloring matter has been isolated, and is called catechin. Both cutch and gambier will dye cotton and wool rich shades of brown, which are quite fast to light when after-treated with copper or chromium salts.