In order that pills may not adhere to one another, they are rolled in an inert powder, such as marsh-mallow, liquorice, and above all, lycopodium. Carbonate of magnesia is now particularly used for pills of turpentine and copaiba. To disguise the peculiar odour of the pill mass, German practitioners use iris powder, or cinnamon.
To render pills more pleasing to the eye, as well as to disguise their taste, instead of rolling them in the before named powders, they are frequently covered with gold or silver leaf. The mode of doing this is too well known to need repetition. We will only remark that those pills which contain iodine, bromine, sulphur, iodides, bromides, sulphides, salts of mercury, gold, platina, &c., cannot be silvered.
These methods conceal but imperfectly the unpleasant taste and smell of certain pillular compounds. M. Garot, to obviate this inconvenience, has proposed to cover pills with a layer of gelatine, by means of a process which he has made public, and into the details of which we think it needless to enter. The gelatinous layer conceals the bad taste and smell perfectly, but it is attended with one inconvenience; in time it shrinks, cracks, and the pill mass exudes. Besides, much skill is required in its manipulation. After gelatinization comes sugaring. This is frequently preferable to the former modes, and can be equally well applied to pills of a repulsive taste and smell, (copaiba, turpentine, musk, assafœtida, &c.,) or to those which are changed by air or light, (proto salts of iron,) or deliquescent, (iod-hydrargyrate of iodide of potassium,) or caustic, (croton oil.) It can extemporaneously be performed in the following manner:—Put the pills into a vase with a round bottom, {147} or into a box lined with silver, moisten them with a little syrup of sugar, clear mucilage, or white of eggs, agitate them so as to moisten them uniformly; add a mixture of equal parts of gum, sugar and starch; again rotate them, so as equally to enclose all the pills. If a first layer be not sufficient, add a second and third in the same manner. Dry them in the air or in a stove. In damp weather, these pills should be enclosed in corked bottles. Gelatine of carragheen or caseine dried and powdered may be substituted for the above powdered mixture. This method is more expeditious than gelatinisation, and it has besides the advantage of the material being always perfectly soluble. Collodion has been proposed for enveloping pills, but seems never to have been used.
The last method we shall call toluisation. It appears to possess many decided advantages over the others. M. Blancard, its originator, employs it particularly for pills of proto iodide of iron. It is to induce its more general use that we make these remarks. The following is the mode of proceeding, which can be modified to suit the daily wants of practice:
Dissolve one part of balsam of tolu, in three parts of ether, (the balsam which has been used in the preparation of syrup of tolu will answer perfectly;) pour some of this tincture into a capsule containing the pills, to favor the evaporation of the ether. When the pills begin to stick together, throw them on a mould of tin passed through mercury, or simply on a plate, taking care to separate those which stick together. Set them in the air to dry. The drying may be completed in a stove of moderate heat, especially if several layers have been found necessary. This mode of enveloping may take the place, or nearly so, of all the others. An important point in it, is, that it resists the effects both of damp and dryness on the pill mass. Its balsamic odour is generally agreeable; but should it not be so, the tolu might be replaced by some inert resin soluble in ether, as mastic tears for example. The layer of resinous matter is so thin, that we apprehend no obstacle in its influence on the medicine. {148}
We will, however, make one general remark, namely: that as each method possesses some peculiar advantages, we thought it right to give them all.—Bulletin Gen. Ther. Med. et Chir. January, 1852.
ON THE APPLICATION OF ORGANIC CHEMISTRY TO PERFUMERY. BY DR. A. W. HOFFMAN. Professor to the Royal College of Chemistry, London.
Cahours’ excellent researches concerning the essential oil of gaultheria procumbens (a North American plant of the natural order of the Ericinæ of Jussieu,) which admits of so many applications in perfumery, have opened a new field in this branch of industry. The introduction of this oil among compound ethers must necessarily direct the attention of perfumers towards this important branch of compounds, the number of which is daily increasing by the labors of those who apply themselves to organic chemistry. The striking similarity of the smell of these ethers to that of fruit has not escaped the observation of chemists; however, it was reserved to practical men to discover by which choice and combinations it might be possible to imitate the scent of peculiar fruits to such a nicety, as to make it probable that the scent of the fruit is owing to a natural combination identical to that produced by art; so much so, as to enable the chemist to produce from fruits the said combinations, provided he could have at his disposal a sufficient quantity to operate upon. The manufacture of artificial aromatic oils for the purpose of perfumery is, of course, a recent branch of industry; nevertheless, it has already fallen into the hands of several distillers, who produce sufficient quantity to supply the trade; a fact, which has not escaped the observation of the Jury at the London Exhibition. In visiting the stalls of English and French perfumers at the Crystal Palace, we found a great variety of these chemical perfumes, {149} the applications of which were at the same time practically illustrated by confectionery flavored by them. However, as most of the samples of the oils sent to the Exhibition were but small, I was prevented, in many cases, from making an accurate analysis of them. The largest samples were those of a compound labelled “Pear oil,” which, by analysis, I discovered to be an alcoholic solution of pure acetate of amyloxide. Not having sufficient quantity to purify it for combustion, I dissolved it with potash, by which free fusel oil was separated, and determined the acetic acid in the form of a silver salt.
0,3080 gram. of silver salt = 0,1997 gram. of silver.