Bologna Phial

Bologna Phial, or PHILOSOPHICAL PHIAL, is a short, thick, narrow glass vessel, close at one end, and open at the other, which the glass-blower prepares from each pot of metal before employing it in the fashioning of tumblers, glasses, bottles, &c. (see GLASS). It serves the purpose of enabling the glass-manufacturer to judge of the colour and other conditions of the fused glass or metal; and as the flask is not subjected to annealing, it is very friable, and a small angular fragment of any mineral allowed to drop into it, at once causes it to fly in pieces. It is curious to notice, however, that a Bologna phial will bear a very heavy blow on the outside without being fractured.