metal just entering the mould, which instantly takes its form by sharp blowing; the brim is then finished, as before explained, by the gaffer, or workman, at the chair. This is an expensive principle of mould making; but it decidedly gives a more polished surface to the bottles, and produces excellent apothecaries' phials of uniform size and capacity. The phial cannot, however, be made of a perfect cylindrical form, as it needs the upper part of the mould to be a slight degree larger than the lower, to allow of the delivery of the bottle from the mould. It is closed by a treadle acting upon two levers with inside springs, which again open the mould when the foot is removed.

All bottle moulds, while working, require to be kept nearly at a red-heat, by means either of a small furnace, or a piece of hot Glass, which is held by a lad inside the mould upon a punty-iron, during the intervals it may be unoccupied by the two blowers. Without this precaution, the surface of the bottles will be ruffled. The heat of the moulds is essential to the polish; but care is requisite to keep the metal moulds, whether brass or iron, a little below red heat, or the Glass will adhere to them.

Moulded Glass, as recently introduced by the English manufacturer, owes its refractive and cut-like effect to its inequalities of substance—the interior having no indentations to correspond with its exterior projections. It requires, in addition to the usual Glass-maker's tools, only a metal mould of about one third the size of the object to be manufactured. The metal is first gathered upon a rod in the ordinary manner, except that the first gathering should be