Calculation rule for the wine trade (Machine-translation by Google Translate, not legally binding)

摘要

A calculation rule for wine trade characterized by being made up of a set consisting of two rules, one fixed and one mobile, with the fixed one on the left, a vertical scale with the alcoholic graduation in tenths of a degree, and on the right a transparent rectangular aperture provided with a red file that serves as an index. (Machine-translation by Google Translate, not legally binding)