2. That plaster diminished the intensity of the color. (This, of course, refers to the direct effect.)
3. That the potassium bitartrate, one of the most useful principles contained in wine, is decomposed by plaster, and that potassium sulphate is formed, which remains in solution, and calcium tartrate, which is precipitated.
4. That potassium phosphate, also one of the salts naturally contained in wine, is equally decomposed by plaster.
5. That plastering profoundly modifies the nature of wines, by substituting for the potassium bitartrate a purgative salt in the proportion of from 3 to more than 7 grammes per litre.
And they demand the exclusion of all wine containing more than 4 grammes of the sulphate per litre.
And Mr. Carles, above quoted, concludes that, owing to the purgative effect of this salt, potassium sulphate, the quantity present should not exceed 2 grammes per litre, or half as much as the army commission allow.
Still later, we have the instructions of the Minister of Justice of France to the procureurs Généraux, issued in 1880, as follows:
After several judicial decisions relative to the sale of plastered wines, one of my predecessors expressed to the Minister of Agriculture and Commerce the desire that new experiments should be made in order to establish, if in the present state of science the immunity accorded to plastered wines by the circular of July 21, 1858, should be maintained.
Having examined the question, the consultation committee of public hygiene issued the following notice:
1. That the absolute immunity which plastered wines enjoy on account of the circular of the Minister of Justice dated July 21, 1858, ought no longer to be officially allowed.