Pour sparkling champagne into a glass until it is half full, when the
glass will lose its power of ringing by a stroke upon its edges, and
will emit only a disagreeable and puffy sound. Nor will the glass ring
while the wine is brisk, and filled with air-bubbles; but, as the
effervescence subsides, the sound will become clearer and clearer,
and when the air bubbles have entirely disappeared, the glass will
ring as usual. If a crumb of bread be thrown into the champagne, and
effervescence be re-produced, the glass will again cease to ring. The
same experiment will also succeed with soda-water, ginger wine, or any
other effervescing liquid.