The division of sialagogues is sufficiently obvious.

There is but one certain internal remedy of this kind. mercury. Yet, from the late experiments with the nitric acid in syphilis, there is some reason to suspect that it may have a similar power. The experience of others, however, has scarcely supported the suspicion, and it is consequently inserted with the mark of doubt. In the other list, though almost all the stimulants might have been inserted, those usually preferred are only enumerated.

In the class of emmenagogues it was necessary to distinguish those which stimulate the system in general, from those whose irritation is confined to the uterus, or whose action is of a different kind. The two first orders contain the general and topical stimulants: the two next the antispasmodics and tonics. All the medicines included in this class are employed, and the distinction will be amply explained under the article Menses.

The stimulantia have occasioned no little difficulty in the arrangements. The diffusibilia and the topica are chiefly distinguished in the Brunonian works; but as we have rejected the principles, we cannot be expected to adopt their consequences. We could not, however, wholly avoid them. Some stimulants are very general in their action, others confined to particular parts. Yet they pass into each other by such imperceptible shades, that we found it difficult to draw the line, and have passed with sufficient accuracy from the more general to the more partial stimulants. The topica are those chiefly of topical application. The insertion of the order indirecta appears to lean to the Brunonian doctrines, and we have explained their action to be of a sedative nature, producing an unequal excitement, and, in consequence, an apparent stimulus. Yet a work of this kind must not only contain the author's own opinions, but those of others: above all, it is necessary to point out that some of these medicines are employed with success as active stimulants.

The refrigerantia are few and simple. The an-tispasmodica, as not connected with general effects, ought perhaps not to have been admitted as a class; but some complaisance is due to former authors, and the first subdivision cannot be referred to any general power. The subdivisions which follow sufficiently show that the power of destroying spasm very commonly depends on its cause.

Toxics are also with difficulty distinguished in their several subdivisions. The natural arrangement is into bitters joined with astringency, pure bitters, and the more pure astringents. Yet it is not easy in the practice, and we have preferred uniting the warm with the purer bitters, and distinguishing them from the narcotic bitters, for reasons which will be obvious on per the article Amara. The subdivision fossilia requires an apology, since it does not point out their peculiar properties; but we could find no suitable appellation, as they have no sensible operation. The more pure astringents follow, which are also tonics.

The sedantia are the refrigerantia or narcotica, and this division requires no remark. The attenuantia are merely diluents, or such medicines as enable the scrosity to dissolve a larger proportion of the gluten. The dulcia are added on the authority of Dr. Stark, who confined himself to a saccharine diet, and, after some time, experienced all the symptoms of sea scurvy. Yet these experiments must be admitted with hesitation, as his constitution, from a series of wanton trials, was previously much debilitated. Diastainsalubris, more strictly unalimentaiy, is founded on the instances which have occurred of the symptoms of scurvy from such diet; but it is not likely to be employed as a remedy.

The remedies included under the inspissantia show that it is highly improbable such a change could be produced by medicines. The remedies for scurvy and the tonics are the only probable means of correcting too great tenuity.

The alterantia contain, as already hinted, the dia-phoretica diapnoica; and the only other remedy which we were able to introduce is diaeta.

The subdivisions of the demulcentia and anta-cida are sufficiently obvious, and not very important, perhaps not chemically correct; but affected minuteness, or extreme accuracy, which would multiply trifling subdivisions, is certainly no improvement. The antalkalina and antiseptica admit of no subdivisions; and those of the emollientia are sufficiently obvious.

The ehodentia are naturally divided into the azo-etica, which destroy the life of a part, and the so/ventia, which consume it. Many of the latter act as azoetics; a term borrowed from the excellent syllabus of Dr. G. Pearson: but it is necessary only to point out the medicines usually employed with either view.

The astringentia are chiefly external remedies; for the internal astringents are enumerated, as already explained, under tonics. The alexiteria, the antidotes, are chiefly those enumerated by authors. The only novelty is the antidote of nitrous air, inserted in consequence of a case lately recorded, where death ensued from a person having copiously inhaled the fumes of nitrous acid from a bottle bursting. From the symptoms it appeared that the oxygen had been separated in the system, and the acid appeared in every excreted fluid. Alkalis, in the first instance copiously taken, would probably have succeeded; and the best form would have been that of soap. The lithontriptics and anthelmintics are those usually enumerated. The last class is peculiarly full, as it has been supposed that we have few medicines of this kind, and of uncertain efficacy. The fact is, that diseases are often attributed to worms when none exist, or when they are not in the slightest degree injurious.

We have thus completed a catalogue of the materia medica on a new plan, more full and complete, we trust, than any yet communicated to the public in general. Its errors may be numerous; but they have not arisen from want of attention, of labour, or observation. Many large works have perhaps cost less pains than the ompilation of these few pages.

Murray Apparatus Medicaminum; Gmelin's Continuation of Murray; Lewis, Cullen, Geoffroy, Linnaeus, Bergius, Spielman, Vogel, and Cartheuser's Materia Medica; Duncan's New Edinburgh Dispensatory; Dr. G. Pearson's very extensive and valuable Syllabus. Materia mercurii salis. See Circulatum. Materiatura. Intemperature. Castellus. Mathae'i Pilulae. Mathew's pill. Starkey was its author, but it was sold by Mathews for him as an universal medicine. It consisted of the soap of tartar, black hellebore, opium, etc.