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Enamelled Cards

mixture, paper, twenty-four and hours

ENAMELLED CARDS is a name given to the cards on which a coating in imitation of real enamel is produced. We believe there are various processes at present employed for fabricating these elegant and fashionable articles ; but the following account of Mr. Christ's process, which we derive from the speci fication of his patent, enrolled in August 1826, may be regarded as genuine and practical. One pound of parchment cuttings, a quarter of a pound of isinglass, and a quarter of a pound of gum arabic, are to be boiled in an open iron pot or other vessel, in twenty-four quarts of pure water, until the solution is reduced to twelve quarts, when it is to be taken off the fire and strained clear. The solution of this consistence is then to be divided into three equal parts of four quarts each ; to the first of these portions is to be added six pounds of pure white lead, (previously ground fine in water,) which is called mixture No.1 ; to the second portion, eight pounds of pure white lead, forming mixture No. 2 ; and to the third is to be added six pounds of pure white lead, making mixture No. 3. The sheets of paper are then to be stretched out upon flat boards and brushed over with a thin coat of No.1 mixture, with a common painter's brush ; the paper is then to be hung up to dry for twenty-four hours. After this, the

paper is m a similar. manner to receive a coat of No. 2 mixture, and to be hung up again to dry for twenty-four hours ; the paper is then to be treated in the like manner with No. 3 mixture, and then dned again for twenty-four hours. It is next to be printed with the engraved plate, and the press-board used for the purpose is to be of smooth cast iron instead of wood. The printing being completed, the paper is to be hung up a fourth time for twenty-four hours to dry; after this it undergoes the final operation of receiving its high gloss, which consists in laying the work with its face downwards on a highly-polished steel plate, and then passing both with great pressure between a pair of cylindrical rollers, and thus the beautifully polished surface of the steel is transferred to the composition on the paper, which closely resembles in appearance the finest white enamel. It is, however, to be regretted that this enamelled surface is not very durable, as it comes off readily after wetting it with the finger. To prevent this, a solution of some resinous substance be added in the lag operation.