Spirit meters, - It may be mentioned that in some countries, though not in the United Kingdom, an "Alcohol meter" or " Spirit meter " is used in distilleries for the purpose of registering automatically the quantity and strength of the alcohol produced. In one form, made by Siemens, the spirit on its way from still to receiver passes into a vessel in which its strength is recorded. For this purpose a float is employed, which, on the principle of the hydrometer, rises in weaker spirit and falls in stronger; and this motion of rise and fall is communicated to a dial indicator by means of a delicate lever mechanism. The vessel is so constructed as to provide for proper mixing of the spirit and to avoid convection effects on the float.

The spirit then passes to the measuring instrument, which consists of a cylinder or drum rotating on a horizontal axis, and divided into three equal compartments by radial planes. When one of the compartments is full, the weight causes the drum to rotate, thus allowing that compartment to discharge, and bringing another into position for filling in the meantime. The rotation is registered on an indicator dial by means of a pinion attached to the axle of the drum. Thus a continuous record of quantity and strength is obtained.

The accompanying table shows for the principal foreign countries the alcoholic strengths corresponding with various percentages of British proof spirit.

Foreign alcoholic strengths corresponding with British proof values.