During the whole Course of this Operation, the Vessel should be kept from all external Cold, or considerable Heat, in an equal, uniform, and moderate Temperature. In the Winter, a Stove-Room, such as is common in Germany, would be very convenient for this Purpose; the Vessel being placed at a proper Distance from the Stove: But at other Seasons no particular Apparatus is necessary with us in England, if the Place allotted for the Business be but well defended from the Summer’s Heat, and the ill Effects of cold bleak northern Winds.
The Operation is known to be perfected when the hissing, or small bubbling Noise can be no longer heard, upon applying the Ear to the Vessel; and also by the Liquor itself appearing clear to Eye, and having a pungent Sharpness on the Tongue. And that it may fully obtain these Properties, and be well fitted to yield a pure and perfectly vinous Spirit by Distillation, it should be suffered to stand at rest in a somewhat cooler Place, if practicable, than that in which it was fermented; till it has thoroughly deposited and cleansed itself of the gross Lee, and become perfectly transparent, vinous and fragrant; in which State it should be committed to the Still, and the Spirit obtained will not only exceed that obtained in the common Way in Quantity, but also in Fragrance, Pungency, and Vinosity.
CHAP. III.
Of Distillation in general.
Having in the two preceding Chapters laid down the best Methods of Brewing and Fermentation, we shall now proceed to the Method of Distillation.
And in order to lead our Readers methodically through the Path which lies before them, we shall begin with explaining the Principles of Distillation; or, the Method of extracting the spirituous Parts of Bodies.
To extract the Spirits is to cause such an Action by Heat, as to cause them to ascend in Vapour from the Bodies which detain them.
If this Heat be natural to Bodies, so that the Separation be made without any adventitious Means, it is called Fermentation, which we have already explained.
If it be produced by Fire, or other heating Power, in which the Alembic is placed, it is called Digestion, or Distillation: Digestion, if the Heat only prepares the Materials for the Distillation of their Spirits; and Distillation, where the Action is of sufficient Efficacy to cause them to ascend in Vapour, and distil.
This Heat is that which puts the insensible Parts of a Body, whatever it be, into Motion, divides them, and causes a Passage for the Spirits inclosed herein, by disengaging them from the Phlegm and the earthy Particles by which they are inclosed.
Distillation considered in this Light, is not unworthy the Attention and Countenance of the Learned. This Art is of infinite Extent; whatever the whole Earth produces, Flowers, Fruits, Seeds, Spices, aromatic and vulnerary Plants, odoriferous Drugs, &c. are its Objects, and come under its Cognizance; but we generally confine it to Liquids of Taste and Smell; and to the simple and spirituous Waters of aromatic and vulnerary Plants. With regard to its Utility, we shall omit saying any thing here, as we shall give sufficient Proofs of it in the Sequel.