believe it our duty to recommend those of our readers who are
particularly interested in this subject to read Mr. Salleron's book on
sparkling wine. We shall confine ourselves in this article to a
description of two of the apparatus invented by the author for testing
the resistance of bottles and cork stoppers.

It is well, in the first place, to say that one of the important
elements in the treatment of sparkling wine is the normal pressure
that it is to produce in the bottles. After judicious deductions and
numerous experiments, Mr. Salleron has adopted for the normal pressure
of highly sparkling wines five atmospheres at the temperature of the
cellar, which does not exceed 10 degrees. But, in a defective cellar,
the bottles may be exposed to frost in winter and to a temperature of
25° in summer, corresponding to a tension of ten atmospheres. It may
naturally be asked whether bottles will withstand such an ordeal. Mr.
Salleron has determined their resistance through the process by which
we estimate that of building materials, viz., by measuring the limit
of their elasticity, or, in other words, the pressure under which they
take on a new permanent volume. In fact, glass must be assimilated to
a perfectly elastic body; and bottles expand under the internal
pressure that they support. If their resistance is insufficient, they
continue to increase in measure as the pressure is further prolonged,
and at every increase in permanent capacity, their resistance
diminishes.

[Illustration: Fig. 1.--MACHINE FOR TESTING BOTTLES.]

The apparatus shown in Fig. 1 is called an elasticimeter, and permits
of a preliminary testing of bottles. The bottle to be tested is put
into the receptacle, A B, which is kept full of water, and when it has