Gelatin, Rough. Syn. Gelatine Brut, Fr. From the skulls of oxen, the spongy insides of the horns and ribs, and from several other soft bony parts (deprived of fat), by washing them in water, digesting in an equal weight of hydrochloric acid of 6° Baume, in cold weather, and 4° or 5° in summer, for 10 days, then in acid of only 1° Baume for 24 hours longer; afterwards soaking and washing in successive portions of cold water until all the acid is washed out, adding an ounce of carbonate of soda to the last water. Used to make glue, &c. A similar article is prepared from the bones of sheep. The pieces, after being treated as above, are steeped in boiling water for a few minutes, wiped dry, and shaken together in a bag to remove the internal pellicle; after which they are cut into squares or dice to disguise them, and finally dipped into a hot solution of gelatin to varnish them. In this state the article is called ‘GELATINE BRUT FIN,’ Used to make soup. It keeps better than the cakes of portable soup. When less carefully prepared, it is also used to make glue for fine work. See Bone gelatin.
GELEE (pour le Goitre). See Liniment of Iodide of Potassium.
GELSEMIUM SEMPERVIRENS. Syn. Gelsemium nitridum, Gelsemium sempervirens, Gelsemium lucidum, Anonymus sempervirens, Bignonia sempervirens; Lisanthus sempervirens. The Yellow jasmine, or WOODBINE. The Carolina jasmine.
Different botanists have placed the plant in different natural orders. De Candolle assigns it to the Loganiaceæ; Decaisne to the Apocynaceæ; Chapman to the Rubiaceæ.
The root, which is the only part of this plant employed in medicine, and of which a fluid extract has been introduced into the United States Pharmacopœia, as met with in English commerce occurs in two states; either in packets prepared by the shakers of New Lebanon, which contain the root in small pieces, formed into a compact mass by hydraulic pressure, and in which state it is difficult to powder; or it is simply sold cut up into pieces varying from two to eight inches in length, and one-third to three fourths of an inch in diameter. It is frequently mixed with about half its bulk of long, wiry, pale-brown rootlets.
The so-called gelsemium root consists chiefly of subterranean stem with a small proportion of true root, occasionally a slender piece of the aërial stem may be found intermixed, and is readily distinguished by its purplish colour and hollow centre, and by the silky and tow-like fibre, rendered visible when the epidermis is peeled off (fig. 1 e).
The true root is hard and woody, slightly undulated in outline, very sparingly branched, except in the slender pieces, externally of a pale brown colour, nearly smooth, and furnished with a thin scurfy cuticle, which is slightly cracked longitudinally. When a transverse section is examined with a lens, the bark of the root is seen to be very thin, and to consist of two layers, the inner one being usually almost as pale as the woody portion, and of somewhat soft texture, the outer one is darker and more compact (fig. 1 b, c).
The meditullium, or woody portion of the root occupies nearly its whole diameter, is of a pale yellowish bright colour, the yellow tint becoming much more distinct when the root is wetted. The medullary rays are white and very distinct, and the woody tissue between the rays is very porous, the pores being very small, but visible to the unaided eye, especially when the root is broken instead of cut (fig. 1 d). There is no pith or central cavity in the root. The root has a bitter taste and pleasant flavour, somewhat between those of senega and green tea; this is more readily perceived in the tincture.
The subterranean stem (fig. 1 a) is also furnished with rootlets, but is easily distinguished from the root by the presence of a small, dark coloured, central cavity representing the pith, and by the external surface being rougher, and frequently variegated with dark longitudinal lines, which are the remains of the same purplish cuticle which presents so marked a feature in the aërial stem. The bark is thicker than that of the true root, and the inner layer is usually dark brown. If the subterranean stem is broken slowly and carefully, a thin row of silky fibres projects fully a quarter of an inch from the broken edge. The fibres do not appear when the bark of the root is broken, and thus serve to distinguish the stem of this drug from the root. Experiments as to the relative value of the bark of the root and stem are wanting. The bark of the stem has the same bitter taste as that of the root, and if it be hereafter shown that it is equally active, the above character of scattered strong fibres, taken in conjunction with the flavour of the drug and its porous structure, will serve to distinguish it from all other roots and stems used in materia medica.[330]
[330] Holmes.