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176 The observations of Mr. Wilde have thrown a confirmatory light on the accounts handed down to us by ancient writers of the mode of procuring the dye. This gentleman, when visiting the ruins of Tyre in 1838, found on the shore a number of round holes cut in the solid rock, varying in size from that of an ordinary metal-pot to that of a large boiler. In these cavities, and scattered on the beach around, lay large quantities of shells, broken, apparently, by design, but subsequently agglutinated together. It was evident that the shells had been collected in quantities, and deposited in the cavities in order to be pounded in the very mode described by Pliny, for the purpose of extracting the purple dye contained in the animal. The broken shells proved, on examination, to be all of one species, Murex trunculus, which was known to have yielded the Tyrian purple, and recent specimens of the same species were found on the adjacent beach.

In this family are placed the largest of univalve shells, such as the Tritonium, of which one species, richly clouded with brown and red like tortoiseshell, is sometimes found two feet in length; and the genus Cassis, well known as Helmet-shells, of triangular form and ponderous structure. All these are highly ornamented, especially the massive kinds from the West Indies and the Indian Ocean. The use of the helmets for the cutting of cameos has been noticed in a former page of this volume; but some statistical details on the same subject may not be uninteresting to my readers. They were communicated by Mr. J. E. Gray to the Society of Arts, in 1847.

Mr. Gray observed that numerous attempts have