1868 The complete Practical Distiller

THE COMPLETE PRACTICAL DISTILLER.

178

With regard to the recommendation which has been made to saturate the acid of the lees with chalk, it is con- sidered to be good ; but the use of chalk is at an end there, it would s5em, and does not in the least contribute to neutralize the essential oil. The solid substances of lees, when dried and burned, give a product which is called ^^ lees ashes ;'' this operation is a true incineration, the products of which are gathered. Among these pro- ducts, which are all of a calcareous nature, the tartrate acid of potash is found in large quantities, and it is to this body, useful to arts, that lees ashes owe their value. It is very often that the residues of the distillation of lees are used as manure, and this agent of reproduction is tolerably appreciated in the vineyards. In fact, it is a true consumption, in the place of pro- duction, which assigns to this mode of working all the advantages which it offers to science and to agricultural purposes. The observations on this article will be brought to a close by giving an extract, made by M. Gay-LussaCj out of a memorial of M. Aubergier on the spirits of lees. This extract, which is taken from the "x\nnalesde Chimie et de Physique,'^ will give further information on what has been said previously concerning the special distilla- tion of lees : ^^ Until the present day, it has been thought that the flavour and the acid and penetrating taste of lees-brandies were owing to a certain oil, which, according to some, was formed during the process of distillation, and accord- ing to others, existed already formed in the kernels of the

raisins.