It appears that the whole of the Elatin does not separate itself from its native juice by spontaneous subsidence, and that, on this account, the supernatant liquor possesses some powers as a cathartic. We cannot be surprised therefore that the Elaterium of commerce should be a very variable and uncertain medicine; for independent of the great temptation which its high price holds out for adulterating it, which is frequently done with starch, it necessarily follows that where the active principle of a compound bears so small a proportion to its bulk, it is liable to be affected by the slightest variation in the process for its preparation, and even by the temperature of the season; where pressure is used for obtaining the juices, a greater or less quantity of the inactive parts of the cucumber will be mixed with the Elatin, in proportion to the extent of such pressure, and the Elaterium will of course be proportionally weak.[[504]] There is one curious result obtained in my experiments which deserves notice, viz. that there is a bitter principle in the Elaterium, very distinct from its extractive matter, and totally unconnected with its activity, for I diluted the solution obtained in experiment G. and swallowed it, but it produced upon me no effect, except that which I generally experience upon taking a powerful bitter,—an increased appetite; and yet notwithstanding this fact, when in combination with Elatin, it is far from being inert, since this latter body is considerably quickened by its presence. See page 152. The solution B was given to a person, but no effect whatever ensued. Dose of good Elaterium, as it occurs in commerce, is about one grain, or it is better to give it only to the extent of half a grain at a time, and to repeat that dose every hour until it begins to operate. It is probably, when thus managed, the best hydragogue cathartic which we possess; it differs however from the class of remedies to which it belongs, for it excites the pulse and whole animal system, so as to produce a considerable degree of febrile action. It was strongly recommended by Sydenham, Lister, and Hoffman, and all their cotemporaries and immediate successors, as a valuable remedy in dropsy; but in consequence of some fatal results from its improper application, it was driven from practice with a violence that marks prejudice rather than conviction; one author, in descanting upon its virulence, exclaims, “Elaterium esse in catalogo diaboli quo necat homines.” For its restoration to medicine, we are indebted to Dr. Ferriar of Manchester, who used it with great success in the cure of Hydrothorax.

Extractum (Succus Spissatus. E.D.) Hyoscyami. L. This preparation is certainly powerfully narcotic, and tends to relax rather than astringe the bowels; where the constitution is rebellious to opium, it furnishes a more valuable resource to the practitioner than any other narcotic extract. Dose, gr. v to ℈j, in pills. See Form. 1, 3, 4, 19, 139.

Extractum Lactucæ. L. Succus Spissatus Lactucæ Sativæ. E. This preparation has found its way into the London Pharmacopœia, in consequence of the testimony of many highly respectable practitioners in favour of its sedative properties. In the memoirs of the Caledonian Horticultural Society, various suggestions are offered as to the best mode of obtaining an extract from the milky juice of the garden Lettuce, to which Dr. Duncan has bestowed the name of “Lactucarium;” it was first recommended to take the milk with cotton, afterwards with a sponge, and more recently with a painter’s brush; all these methods however are attended with considerable difficulty, and the juice cannot be collected in any quantity. Mr. Probart, a chemist in Great Portland Street, has lately cultivated large plantations of the lettuce, for the purpose of instituting experiments upon the subject, and I am happy in being enabled through his liberality, to introduce in this place, an account of the process which he pursues, and which he considers the only one by which the article can be brought into the market at any reasonable price.[[505]]

In concluding the history of Inspissated juices, it deserves notice that the London College uniformly directs that the feculence should be preserved in the compound: there can be no doubt of the propriety of such advice, but the Colleges of Edinburgh and Dublin reject it. The French Codex gives directions for two extracts from each of these substances, one containing what they please to denominate the fecula, the other not; thus there is “Extractum Cicutæ absque Fecula” and “Extract: Cicut: cum Fecula.” There is one curious fact respecting these narcotic preparations, that most, if not all of them, contain nitre, common salt, and muriate of potass.

Manufacturing chemists, in order to give a smooth and glossy appearance to their Extracts, generally add to every ℔j, about ʒss of gum, fʒj of olive oil, and ♏︎xx of rectified spirit; there is no harm in the practice.

FERRI SUB-CARBONAS. L. Carbonas Ferri

Præcipitatus. E. Carbonas Ferri. D.

Carbonate of Iron.

In a former Pharmacopœia of London, a sub-carbonate of iron was prepared, under the name of ferri-rubigo (rust of iron,) by exposing iron-filings to the action of air and water; and although the Colleges of Edinburgh and Dublin still retain this mode of preparation, yet they admit at the same time of another which, like the sub-carbonate of the present London Pharmacopœia, is produced by precipitation. Qualities. Form, a chocolate brown powder. Odour, none. Taste, slightly styptic. Chemical Composition. Mr. Phillips has shewn that this precipitate is liable to vary according to the temperature at which it is prepared, as well as from other differences of manipulation; it generally consists of mixtures of peroxide, and proto-carbonate of iron, in the proportion of four parts of the latter, and six of the former. By referring to the Medicinal Dynameter the practitioner may find the quantity of those ingredients in any given weight of the preparation, and compare its strength with the other chalybeate medicines. Solubility. It is insoluble in water, but acids dissolve it with effervescence. Forms of Exhibition. In powder or pills, combined with aromatics. Dose, gr. v to xxx. (Form. 38.) It has lately been brought into particular notice by the publication of Mr. Hutchinson of Southwell, who states that in doses of half a drachm to a drachm, two or three times a day, it has proved in his hands a most efficacious remedy in the cure of Tic doloureux. Mr. Hutchinson is well known to the profession as a judicious and inquiring practitioner, and we are well satisfied that he would not recommend any remedy to the attention of his brethren, without a well grounded assurance of its efficacy; at the same time it must be remembered that this disease is very frequently the consequence of an irritation in some nerve, by the mechanical operation of osseous spiculæ; in such cases we cannot expect the sub-carbonate of Iron to afford relief. A noble Marquis who lost his leg at Waterloo, suffered excruciating pains in his face, in consequence of exfoliation in the stump, which were relieved as soon as the local irritation subsided; and a late lamented physician appears to have owed his severe sufferings to the irritation produced on the brain by a bony excrescence. I have little doubt if cases of Tic doloureux were more carefully examined, they would be frequently found to derive their origin from a similar source. If it were necessary I could add several of such instances to those already enumerated.[[506]]

FERRI RAMENTA ET FILA. L. Fila et