The current of spirits is regulated at the entrance by the cock, R, which, through its division plate, gives the exact discharge per hour.  In addition, in order to secure great regularity in the flow, there is placed between the voltameters and the reservoir that supplies them a second and constant level reservoir regulated by an automatic cock.

In practice, Mr. Naudin employs 12 voltameters that discharge 12 hectoliters per hour, for a distillery that handles 300 hectoliters of impure spirits every 24 hours.  The electric current is furnished to the voltameters by a Siemens machine (Fig. 3) having inductors in derivation, the intensity being regulated by the aid of resistance wires interposed in the circuit of the inductors.

The current is made to pass into the series of voltameters by means of a commutator, and its intensity is shown by a Deprez galvanometer.  The voltameters, as shown in the diagram, are mounted in derivation in groups of two in tension.  The spirits traverse them in two parallel currents.  The Siemens machine is of the type SD2, and revolves at the rate of 1,200 times per minute, absorbing a motive power of four horses.

[Illustration:  FIG. 3.—­ARRANGEMENT OF THE SIEMENS MACHINE.]

The disacidification, before entering the rectifier, is effected by the metallic zinc.  Let us now examine what economic advantages this process presents over the old method of rectifying by pure and simple distillation.  The following are the data given by Mr. Naudin: 

In ordinary processes (1) a given quantity of impure alcohol must undergo five rectifications in order that the products composing the mixture (pure alcohol, oils, etc.) may be separated and sold according to their respective quality; (2) the mean yield in the first distillation does not exceed 60 cent.; (3) the loss experienced in distillation amounts, for each rectification, to 4 per cent.; (4) the quantity of essential oils (mixture of the homologues of ethylic alcohol) collected at the end of the first distillation equals, on an average, 3.5 per cent.; (5) the cost of a rectification may be estimated at, on an average, 4 francs per hectoliter.

All things being equal, the yield in the first operation by the electric method is 80 per cent., and the treatment costs, on an average, 0.40 franc per hectoliter.  The economy that is realized is therefore considerable.  For an establishment in which 150 hectoliters of 100 deg. alcohol are treated per day this saving becomes evident, amounting, as it does, to 373 francs.

We may add that the electric process permits of rectifying spirits which, up to the present, could not be rectified by the ordinary processes.  Mr. Naudin’s experiments have shown, for example, that artichoke spirits, which could not be utilized by the old processes, give through hydrogenation an alcohol equal to that derived from Indian corn.—­La Nature.

* * * * *