The operation of bottling the wine next ensues, when the Scriptural advice not to put new wine into old bottles is rigorously followed. For the tremendous pressure of the gas engendered during the subsequent fermentation of the wine is such that the bottle becomes weakened and can never be safely trusted again. It is because of this pressure that the champagne bottle is one of the strongest made, as indicated by its weight, which is almost a couple of pounds. To ensure this unusual strength it is necessary that its sides should be of equal thickness and the bottom of a uniform solidity throughout, in order that no particular expansion may ensue from sudden changes of temperature. The neck must, moreover, be perfectly round and widen gradually towards the shoulder. In addition--and this is of the utmost consequence--the inside ought to be perfectly smooth, as a rough interior causes the gas to make efforts to escape, and thus renders an explosion imminent. The composition of the glass, too, is not without its importance, as a manufactory established for the production of glass by a new process turned out champagne bottles charged with alkaline sulphurets, and the consequence was that an entire _cuvée_ was ruined by their use, through the reciprocal action of the wine and these sulphurets. The acids of the former disengaged hydrosulphuric acid, and instead of champagne the result was a new species of mineral water. Most of the bottles used for champagnes come from the factories of Loivre (which supplies the largest quantity), Folembray, Vauxrot, and Quiquengrogne, and cost on the average from 28 to 30 francs the hundred. They are generally tested by a practised hand, who, by knocking them sharply together, professes to be able to tell from the sound that they give the substance of the glass and its temper. The washing of the bottles is invariably performed by women, who at the larger establishments accomplish it with the aid of machines, sometimes provided with a revolving brush, although small glass beads are more generally used by preference. After being washed every bottle is minutely examined to make certain of its perfect purity. [Illustration] [Illustration]