Licence: Public Domain Mark
Credit: Specification of John Henry Johnson : capsules. Source: Wellcome Collection.
![Johnson’s Improvements in the Manufacture of Capsules. composition of substances, and of an improved means of producing such capsules. The capsules are composed of a mixture of the following substances in about the under mentioned proportion, videlicet,— about 1 part by weight of best gelatine, 5 „ 1-| „ „ chemically pure glycerine, „ 2J „ „ distilled water. The before-mentioned substances are melted in a bath and carefully stirred in order to obtain a semi-liquid of the consistence of syrup, and then clarified. .. ^ M In manufacturing the capsules moulds or formers are employed com¬ posed of any materia] adapted to the same liquid they are subsequently intended to receive, and made of a corresponding shape to the capsules to be produced. > . In the operation of making the capsules the operator lays hold of the 15 former by a handle, with which it is provided, and dips it into the semi-liquid mass, whereby such former becomes coated therewith, care being taken by a quick and dexterous turning of the former to spread the last drop equally over the whole surface in such a manner as to cause the part where the handle is situate to be covered to a somewhat 20 greater thickness than the other portions. In order to effect the removal of the capsules from the “ formersf) (which operation may take place after the lapse of, say, from half to one hour from the time of the operation of dipping) the capsule is cut round with a cutting tool close to the handle, the portion of the composition 25 which may remain on the handle is cleaned away, and the capsule now prepared is drawn down from off the former ” by a quick but uniform rolling motion. The capsule is then to be filled, after which the closing of the filled up capsules is effected with the same composition by the 30 employment for this purpose of a round horn or socket, having a ring, made, say, for example, of silver wire corresponding with the aperture to be closed. The wired horn or socket is dipped into the semi-liquid, its opening being covered therewith, and then placed upon the capsule, so as to enclose the open end of the same, which is in this manner 35](https://iiif.wellcomecollection.org/image/b30751640_0006.jp2/full/800%2C/0/default.jpg)
