1911 Encyclopædia Britannica/Vermouth

VERMOUTH, an alcoholic beverage, the basis of which consists of a fortified and aromatized white wine. The best French vermouth is made from the white wines of the Hérault district. The wine is fortified with spirit up to a strength of about 15% of alcohol, and is then stored in casks exposed to the sun’s rays for a year or two. Another portion of the wine is fortified up to a strength of about 50% of alcohol, and in this various aromatic and tonic materials are macerated, in casks which are exposed to the sun in the same way as the bulk of the wine. The two liquids are then mixed in such proportions as to make the strength of the ultimate product about 17% of alcohol by volume. Excellent vermouth is also manufactured in Italy, the produce of that country being generally of a “sweet,” that made in France of a “dry” type.