Simple Apparatus for Making Ethereal Tinctures, Etc., by Percolation.
By JOHN CALVERT.
No. 1 is the reservoir; No. 2 is the percolator; No. 3 is the receiver.
The lower orifice of No. 1 is connected with No. 2 by means of a short piece of vulcanized rubber tubing.
The receiver is marked to indicate a pint.
To make a pint of ethereal tincture of cantharides, or blistering liquid, sixteen troy ounces of powdered cantharides are put into the percolator; a plug of tow is inserted in the neck, followed by the cork carrying the glass tube. The bottle is inverted and its contents packed as closely as possible, by gently slapping the sides of the vessel with the hand. The side orifice near the bottom of the percolator is then connected with the reservoir by means of the rubber tube. The reservoir stands on a shelf; the percolator is supported by the rings of a retort stand. The cork of the receiver is first slipped on to the glass tube of the percolator, and then brought down into the neck of the receiver. This cork should have a small escape-hole in it. The apparatus is now ready.
The ethereal mixture, consisting of a pint of rectified ether and three ounces of acetic ether, is poured into the reservoir, and the cork inserted. The flow is determined by raising the cork of the reservoir from time to time. When the ethereal liquid has completely permeated the powder, the supply of ether is stopped. The drug should be allowed to macerate for a few hours, after which the percolation may proceed, drop by drop. A pinch-cock on the rubber tube will regulate the flow. As soon as the reservoir is emptied, half a pint of alcohol is poured in, and, when again empty, water is employed to finish the displacement.
If a steady stream of the menstruum is desired, a small piece of glass tube is passed through the cork of No. 1, and connected, by means of rubber hose, with a similar piece through the cork of No. 3. Equilibrium is thus maintained.
The exhausted powder may be removed from the percolator by means of a stream of water, which is injected through the smaller orifice by the aid of a hose attached to the faucet of the water supply.—Proc. Cal. Phar. Soc., 1883, p. 40.