the chemistry of colours, or other constituents of Glass; and still less upon the modes of blowing, shaping, or moulding, this artistic manufacture. One of the chief objects of the present work is to supply this defect, by concentrating within a practical focus the rays of information to be found in the works of Neri, Merrett, Kunkell, Blancourt, Loisel, Deaudenart, Bontemps, and others; and to blend with their researches certain Curiosities of Glass Manufacture, familiar to those practically engaged in Glass Works, but comparatively little known to amateurs of the Art, and those who take interest in its very elaborate details; this portion of the present volume being the result of my own experience and investigation.

The value of researches into the skill of by-gone ages in order to benefit the arts of our own times—more especially with the powerful aid of the present state of chemical science—is strikingly illustrated in Glass Manufacture. But for the existence of the Portland and Naples Vases, part of an ancient Vase in the possession of Mrs. Aldjo, and some interesting fragments from the ruins of Thebes, Pompeii, Rome, and Roman London, we should have been unacquainted with the high art of ancient Glass Cameo Engraving; ad many Glass colouring constituents and manipulatory processes which now excite our admiration and imitation.