OCR Text |
Show 610 COMMON SCURVY-GRASS. COMMON SCURVY-GRASS. 611 not susceptible of alteration, and with sub-acid juices, as that active matter, or its disposition to exhale. of lemons. Byrest these undergo a kind of slight fermentation, and all their mucilaginous and other viscid parts separate. Fil. tration is perhaps the most perfect means of defecation, but it is tedious, and applicable only to very fluid juices. In manyin- virtue of scurvy-grass may, by the above method, be preserved stances it maybe facilitated by the addition of water. ‘The ac. tion of heat is more expeditious, and is employed for juices arum root, iris root, bryony root, and other vegetables, in like which are very alterable, or which contain volatile matters. It is performed by introducing the juice into a matrass, andim. mersing it in boiling water for some minutes. The fecule are coagulated, and easily separated byfiltration. Clarification by white of egg can only be used for very viscid mucilaginous Even the volatile almost entire in its juice for a considerable time; while the active parts of the juice of the wild cucumber quickly separate and settle to the bottom, leaving the fluid part inert. Juices of manner allow their medicinal parts tosettle at the bottom. If juices are intended to be kept for anylengthof time, about one-fortieth part of their weight of good spirit of wine may be added, and the whole suffered to stand as before: a fresh sediment will now be deposited, from which the liquor is to be pouredoff, strained again, and put into small bottles which have been washed with spirit, and dried. A little oil is to be poured juices, which contain nothing volatile. The white of two eggs maybe allowed to cach pint of juice. ‘They are beat to fine on the surface, so as yery nearly to fill the bottles, and the froth, the juice gradually mixed with them, and the whole mouths closed with leather, paper, or stopped with straw, as brought to ebullition. The albumen coagulating, envelopsall the parenchymatous and feculent matters, and the juice now passes the filter readily. By this process juices are rendered sufliciently fine; but the heat employed deepens their colour, the flasks are in which Florence oil is brought to us: this serves to keep out dust, and suffers the air te escape, which, in process of time, arises fromall vegetable liquors, and which would and manifestly alters them, so that it is not merely a defecating but a decomposing process. When depurated, juices are yel- lowor red, but never green. The fluids thus extracted from succulent fruits, whetheracid or sweet; from most of the acrid herbs, as scurvy-grass and water-cresses ; from the acid herbs, as sorrel and wood-sorrel; from the aperientlactescent plants, as dandelion and hawkweed; and from various other vegetables, contain great part of the peculiar taste and virtues of the respective subjects. The juices, on the other hand, extracted from most of the aromatic herbs, have scarcely any thing of the flavour of the plants, and seem to differ little from decoctions of them made in water boiledtill the volatile odorous parts have been dissipated. Many of the odoriferous flowers, as the lily, violet, hyacinth, not only impart nothing of their fragrance to their juice, but have it totally destroyed by the previous bruising. From want of suflicient attention to these particulars, practitioners have been frequently deceived inthe effects of preparations of this class: juice of mint has beenoften prescribed as a stomachic, though it wants those qualities by which mint itself and its other preparations operate. There are differences as great in regard to their preserving those virtues, and this independently of the volatility of the otherwise endanger the bursting of the glasses; or, being imbibed afresh, render their contents vapid and foul. The bottles are to be kept on the bottom of a goodcellar or vault, placed up to the necks in sand. By this method some juices may be preserved for a year or two, and others for a much longer time; though, whatever care be taken, they are found to answer better when fresh; and, from the difficulty of preserving them, they have of late been very muchlaid aside, especially since we have been provided with more convenient and useful remedies. |