[The boneset is a plant indigenous to the United States, and is to be found in the neighbourhood of marshes and low situations. It is intensely bitter and somewhat astringent. According to the analysis of Dr. Andrew Anderson of New-York, it yields, 1. A free acid; 2. Tannin; 3. Extractive matter; 4. A gummy matter; 5. A resin; 6. Azote; 7. Lime, probably the acetate of lime; 8. Gallic acid, probably modified; 9. A resiniform matter, soluble in water and in alcohol, and which seems to contain a bitter principle. It also appears from this analysis that the free acid may be obtained from all parts of the plant—that tannin is obtained in much the largest quantity from the leaves, and least from the roots—that the extractive and gummy matter reside chiefly in the roots—that the leaves and flowers also contain a larger proportion of resin than the roots—and that azote exists in the flowers, leaves, and roots. The principal properties of the boneset are those of a tonic and diaphoretic. The diseases in which it has been prescribed with success are intermitting and remitting fevers, typhoid peripneumony and catarrh. It may be given in powder, infusion, or tincture. When given as a tonic, the tincture is the preferable form. The dose of the powder is from 20 to 30 grains. When used as a sudorific, it is to be taken in infusion, and in large quantities.]
EUPHORBIA IPECACUANHA.
American Ipecacuanha. Radix.
[This plant is peculiar to the United States. The root is perennial, and of a sweetish taste. By analysis it yields caoutchouc, resin, mucus, and fecula. In its medicinal properties it resembles, and perhaps equals, the common ipecacuanha. As an emetic the dose is from 15 to 25 grains.]
EUPHORBIÆ GUMMI-RESINA. L.
(Euphorbia Officinarum.) Euphorbium.
Qualities. This substance is imported from Barbary, in drops or irregular tears; its fracture is vitreous; it is inodorous, but yields a very acrid burning impression to the tongue. Chemical Composition. It is what is termed a gum resin, but its acrid constituent is exclusively in that portion which is soluble in alcohol, and which might be named Euphorbin; it appears to form as much as 37 per cent. to which are added of wax 19, malate of lime 20·5, malate of potass 2, and water 5. Solubility. Water by trituration is rendered milky, but dissolves only one-seventh part; and alcohol one-fourth of it. Uses. Internally administered, it proves very violently drastic, but it is never employed except as an errhine, cautiously diluted with starch, or some inert powder. The Indian practitioners administer it as a purge in obstinate visceral obstructions; and in those cases of costiveness which so often attend an enlargement and induration of the spleen and liver. Farriers use it for blistering horses, and there is good reason to believe that it is sometimes fraudulently introduced to quicken the powers of our Emplastrum Cantharidis. It enters as an ingredient into a plaster, which has been much celebrated by Cheselden and others, as a stimulating application, to relieve diseases of the hip-joint, and to keep up inflammation of the skin in chronic states of visceral inflammation; the following is its composition. ℞. Emplast: Picis comp: ℥iv.—Euphorbiæ gum-resinœ ʒss.—Terebinth: Vulgar, q. s. Caution, in pulverizing this substance, the dispenser should previously moisten it with vinegar to prevent its rising and excoriating his face.
EXTRACTA. L.E.D. Extracts.
These preparations are obtained by evaporating the watery or spirituous solutions of vegetables, and the native juices obtained from fresh plants by expression, to masses of a tenacious consistence. The London college does not arrange the extracts under the titles of watery and resinous, which is the arrangement of the Edinburgh Pharmacopœia, nor under those of simple and resinous, which is the division observed in that of Dublin, but rejecting all specific distinctions, includes, under the generic appellation of extract, both the species, as well as all the inspissated juices. Since however the former of these arrangements will afford greater facilities for introducing the observations which it is my intention to offer, it is retained in this work.
The chemical nature of extracts must obviously be very complicated and variable, depending in a great degree upon the powers of the menstruum employed for their preparation; although Fourcroy and Vauquelin considered that one peculiar principle was the basis of them all, which they called Extract, Extractive, or the Extractive Principle. It is distinguished by the following characters, viz.