CHAP. III.
Of increasing the Virtues of Simple Waters
by means of Cohobation.
By Cohobation is meant the returning the distilled Water procured in the manner described in the preceding Chapter, upon more of the fresh Plant. The Operation is performed in the following manner:
Take the Plant and Liquor remaining in the Still after the Operation described in the foregoing Chapter is performed, and press them strongly in a Bag for that Purpose, that all the Decoction may be obtained; and with this mix all the Water before drawn over. Return this Mixture into the Still, and a fresh Quantity of the same Plant, and if necessary, as much Water as will make the former Proportion to the Plant. Close all the Junctures exactly, and digest the whole in a gentle Degree of Heat for three Days and three Nights, that the Herb, being so long steeped in its own Liquor, may be opened, loosened, and disposed the easier to part with its Virtues. This Digestion is of great Service; but if protracted too long, introduces a Change tending to Putrefaction. Let the Water now be distilled off, in the same manner as before; only proceeding more cautiously, and somewhat more slowly at first; because the Liquor in the Still being now thicker, more impregnated with the Plant, and therefore more apt to smell upon feeling the Fire, it easily boils over; but after about half of the expected Water is come off, the Fire may be gradually raised.
By this Method, and carefully observing to change the Receiver, as soon as the first Water is all come over, a noble Liquor, highly impregnated with the Virtues of the Plant, will be obtained. And as this Operation may be repeated as often as desired, the Virtues of Plants may be thus exalted to any Degree the Artist shall think proper; which shews the extraordinary Power of Distillation. This Method I would particularly recommend for making the simple Water of Balm, Elder Flowers, Roses, and the like Simples, but sparingly furnished with an essential Oil.