In modern times several attempts have been made to obtain this dye; but the discovery of cochineal has rendered it a matter of little import.
In the year 1683, Mr. William Cole, of Bristol, being at Minehead, was told of a person living at a seaport in Ireland, who had made considerable gain by marking with a delicate and durable crimson colour, fine linen that was sent to him for that purpose, and that this colour was made from some liquid substance taken from a shell-fish. Mr. Cole, being a lover of natural history, and having his curiosity thus excited, went in search of these shell-fish, and, after trying various kinds without success, he, at length, found considerable quantities of a species of buccinum on the sea-coasts of Somersetshire, and the opposite coasts of South Wales. After many ineffectual endeavours, he discovered the colouring-matter, placed in a white vein, lying transversely in a little furrow, or cleft, next to the head of the fish, “which,” says he, “must be digged out with the stiff point of a horse-hair pencil, made short and tapering, by reason of the viscous clamminess of the white liquor in the vein, that so by its stiffness it may drive in the matter into the fine linen or white silk intended to be marked.” Letters or marks, made in this way, with the white liquor in question, “will presently appear of a pleasant green colour, and, if placed in the sun, will change into the following colours,—that is, if in Winter, about noon, if in the Summer, an hour or two after sunrise, or so much before setting, (for in the heat of the day, in Summer, the colours will come so fast that the succession of each will scarce be distinguishable,) next to the first light green will appear a deep green, and in a few minutes this will change into a full sea-green, after which, in a few minutes more, it will alter into a watchet blue, and from that, in a little time more, it will be of a purplish red, after which, lying an hour or two, (supposing the sun still shining,) it will be of a very deep purple red, beyond which the sun can do no more.”
“But the last and most beautiful colour, after washing in scalding water and soap, will (the matter being again exposed to the sun or the wind to dry,) be a much different colour from all those mentioned, that is, a fair bright crimson, or near to the prince’s colour, which afterwards, notwithstanding there is no styptic to bind the colour, will continue the same, if well ordered, as I have found in handkerchiefs that have been washed more than forty times, only it will be somewhat alloyed from what it was after the first washing.”
Some years after this, Réaumur discovered great numbers of a species of buccinum, on the coast of Poitou, and the stones, round which they had collected, were covered with small oval masses, some of which were white, and others of a yellowish colour; and, having squeezed some of them on the sleeves of his shirt, in about half an hour he found it stained of a fine purple colour, which he was unable to discharge by washing. In repeating his experiment on his return home, he found it was necessary that the cloth should be exposed to the direct rays of the sun.
The difficulty of procuring and preserving a sufficient number of these shell-fish, must always render the use of this dye very limited; but Dr. Bancroft is of opinion, that it might still be rendered beneficial in staining or printing fine muslins, for which purpose but little colouring-matter is required. No substance, he remarks, will afford a substantive purple of equal beauty and durability, and capable of being applied to linen or cotton with so much simplicity and expedition.
Family ALATA.
This family is distinguished, by having a canal of variable length at the base of its opening, and by the fact of the right margin of the shell changing its form during the growth of the animal.
The Spotted Scorpion Shell, ([Pterocera scorpio].)
This curious shell is found in the East Indian seas, and attains a considerable size, as much as six inches. In an early age the projecting claws of this shell are very small, so that its appearance is materially different from that which it assumes at a more advanced period of its growth. It is known as the Spotted Scorpion Shell, and is distinguished from other species of the same genus, by the knotted and granulated appearance of its surface; the opening of the shell is long and narrow, and of a dull violet red, sometimes brownish, on which numerous transverse wrinkles are seen, either of a pure white, or slightly tinged with yellow.