Other writers believe that glass was in more general use in the ancient than in comparatively modern times, and affirm that among the Egyptians it was used even as material for coffins. It is certainly true that so well did the Egyptians understand the art, that they excelled in the imitation of precious stones, and were well acquainted with the metallic oxides used in coloring glass; and the specimens of their skill, still preserved in the British Museum and in private collections, prove the great skill and ingenuity of their workmen in mosaic similar in appearance to the modern paper-weights. Among the specimens of Egyptian glass still existing is a fragment representing a lion in bas-relief, well executed and anatomically correct. Other specimens are found inscribed with Arabic characters. All writers agree that the glass-houses in Alexandria, in Egypt, were highly celebrated for the ingenuity and skill of their workmen, and the extent of their manufactures. Strabo relates that the Emperor Hadrian received from an Egyptian priest a number of glass cups in mosaic, sparkling with every color, and deemed of such rare value that they were used only on great festivals. The tombs at Thebes, the ruins of Pompeii and Herculaneum, and the remains of the villa of the Emperor Tiberius, go not only incidentally to establish the antiquity of the art, but also prove the exquisite taste and skill of the artists of their various periods. The first glass-houses, well authenticated, were erected in the city of Tyre. Modern writers upon the subject generally refer to Pliny in establishing the fact that the Phoenicians were the inventors of the art of glass-making. The tradition is that the art was originally brought to light under the following circumstances. A vessel being driven by a storm to take shelter at the mouth of the river Belus, the crew were obliged to remain there some length of time. In the process of cooking, a fire was made upon the ground, whereon was abundance of the herb "kale." That plant burning to ashes, the saline properties became incorporated with the sand. This causing vitrification, the compound now called glass was the result. The fact becoming known, the inhabitants of Tyre and Sidon essayed the work, and brought the new invention into practical use. This is the tradition: but modern science demonstrates the false philosophy, if not the incorrectness, of Pliny's account; and modern manufacturers will readily detect the error, from the impossibility of melting silex and soda by the heat necessary for the ordinary boiling purposes. It is a well-authenticated fact, however, that there were whole streets in Tyre entirely occupied by glass-works; and history makes no mention of any works of this character at an earlier period than the time mentioned by Pliny.