Pills are masses of a consistence sufficient to preserve a round form, yet not so hard as to be of too difficult solution in the stomach. This form of preparation is particularly adapted for medicines which have a very nauseous taste or flavour, and such as operate in minute doses. Extracts, when not too hard, may be formed into pills without any addition; but more generally pills are composed of either vegetable, or earthy, or metallic powders, combined by means of syrup into a coherent mass. Salts also may be formed into pills, except such as are deliquescent; and when efflorescent salts are used, they should be first freed from the water of crystallisation, for the pills formed with uneffloresced salts which are apt to effloresce fall into powder as they dry. The masses which are ordered to be kept prepared for the formation of pills require to be preserved in covered pots, wrapped in bladders, and occasionally moistened. When they are to be formed into pills, a given portion of the mass is rolled into a cylinder, the length of which is regulated by the number of pills into which it is to be divided; and the division is effected either as equally as possible by the hand, or by a machine invented for the purpose. This machine consists of two pieces.

The first, a, is divided into three compartments; 1. a vacant space to receive the divided mass, which is to be rolled into pills; 2. a grooved brass plate, which assists in dividing the mass into pills; and, 3. a box for containing a powder for covering the pills after they are formed. The second, b, consists of a brass plate 1, grooved to match the plate 2 on piece a, and bounded at both ends by moveable projecting plates 2 2, containing two wheels under the ledge of the plate 2; and a wooden back 3, with two handles, 4 4, to which this plate is affixed. In using the machine the cylindrical mass is placed on 2 a; and divided by passing b over it, the wheels of b, enabling it to run easily, being applied to a brass plate which forms the margin of a.

After the round form is given to each of the pills, by rolling the divided pieces between the fingers, they are dropped into 3 a, and covered by some dried powder: as, for instance, subcarbonate of magnesia or starch, to prevent them from adhering. With the same intention pills were formerly, and, in a few instances, are still gilded and silvered; but simple dry powders answer all the purposes of these coverings.

Pilulae Aloes Compositae. Lond. Compound Aloetic Pills

"Take of aloes, powdered, an ounce; extract of gentian, half an ounce; oil of carraway, forty minims; syrup, a sufficient quantity. Beat them together until they are incorporated."

Pilulae aloeticae, Edin. Aloetic Pills.

"Take of socotorine aloes, in powder, soap, of each equal parts. Beat them with simple syrup, so as to make a mass fit for forming pills."

Pilulae Aloes compositae, Dub. Pills of Aloes and Ginger.

"Take of hepatic aloes, an ounce; ginger root, in powder, a drachm; soap, half an ounce; essential oil of peppermint, half a drachm. Let the aloes and the ginger be rubbed together to a powder: then add the soap and the oil, so as to form a mass."

Syn. Pilules d'Aloe composee (F.), Pillole d'Aloe composte (I.)

In the London preparation, the quantity of extract of gentian ordered is too large: owing to its reaction on the aloes, the mass becomes too soft to form into pills: at all events, no syrup is required. The soap in the two other formulae is well adapted for giving consistence and form to the aloes. This is an useful pill: it is employed for obviating the habitual costiveness of the sedentary, and of leucophlegmatic habits. The dose is from grs. x. to grs. xv. or more.