THE GLASS-BLOWER’S TABLE.
Artists give this name to an apparatus which consists of the following articles:—
1. A Table, below which is disposed a double bellows, capable of being put in motion by means of a pedal. This bellows furnishes a continued current of air, which can be directed at pleasure by making it pass through a tube terminating above the table in a sharp beak. The bellows with which the glass-blower’s tables are commonly furnished have very great defects. The irregular form which is given to the pannels diminishes the capacity of the instruments, without augmenting their advantages. If we reflect an instant on the angle, more or less open, which these pannels form when in motion, we instantly perceive that the weight with which the upper surface of a bellows is charged, and which always affords a vertical pressure, acts very unequally on the arm of a lever which is continually changing its position. This faulty disposition of the parts of the machine has the effect of varying every instant the intensity of the current of air directed upon the flame. All these inconveniences would disappear, were the upper pannel, like that in the middle, disposed in such a manner as to be always horizontal. It ought to be elevated and depressed, in its whole extent, in the same manner; so that, when charged with a weight, the pressure should be constantly the same, and the current of air uniform.
2. A lamp, of copper or tin plate.—The construction of this article, sufficiently imperfect until the present time, has varied according to the taste of those who have made use of it. We shall give, farther on, the description of a lamp altogether novel in its construction.
3. The glass-blower’s table is generally furnished with little drawers for holding the tools employed in modelling the softened glass. Careful artists have the surface of their table coated with sheet iron, in order that it may not be burned by the hot substances that fall, or are laid upon it. As glass-blowers have frequent occasion to take measures, it is convenient to have the front edge of the table divided into a certain number of equal parts, marked with copper nails. This enables the workman to take, at a glance of the eye, the half, third, or fourth of a tube, or to give the same length to articles of the same kind, without having perpetual recourse to the rule and compasses. But when it is desirable to have the tubes, or the work, measured with greater exactness than it can be measured by this method, the rule and the compasses can be applied to.