Connected with these are malting and bottling works.
In the spring-time, shortly after bottling, the rise in temperature produces a secondary fermentation, and this converts the sugar into alcohol and carbonic acid.
An attack from the Trentino with the object of cutting the Italian communications with the Julian front, and so bottling Cadorna's main force in what Krauss calls " the Venetian sack," was an operation which could not but commend itself to the Austrian general staff.
It is then ready for bottling, but previous to this operation it is necessary to ascertain whether the wine contains sufficient remanent sugar to develop the " gas " necessary for effervescence.
The vintage date, therefore, which is borne by " vintage champagne," refers rather to the date of vintage prior to bottling than to the age of the wine, although the main bulk of the wine of a certain " vintage " will actually have been made in the year indicated.