accompanied with weakness and lameness of the part affected.
The cure of this disorder should at first be attempted with restringents and bandages, which will be found very efficacious in strengthening the joints; but if these should fail in reducing the vein to its natural size, the skin must be opened, and the vein tied with waxed thread passed under it with a crooked needle, both above and below the swelling, and the turgid part suffered to digest away with the ligatures: for this purpose, the wound should be daily dressed with a mixture of turpentine, honey, and spirit of wine.
BLOOD-STONE, or Hematites, is a hard mineral substance of a red or purple colour. It is found in masses of different forms, and contains a considerable portion of iron, insomuch, that forty pounds of that metal have been extracted from a quintal of the stone. The iron is of a very inferior quality, and therefore seldom used; but the blood-stone itself, on account of its hardness, serves to burnish or polish metals.
Dragon's Blood. See Dragon.
BLOOD-LETTING, in surgery, is performed with a view either to diminish the quantity of the circulating fluid, or to relieve a particular part, in case of inflammation, and, consequently, it is either general or local.
General blood-letting, is that which is performed upon a vein or an artery: hence we have the terms phlebotomy and arteriotomy.
Local, or topical blood-letting, is performed by scarification and cupping-glasses, by leeches, or by punctures made with a lancet, according to the nature of the disorder. This latter, or topical blood-letting, is never dangerous, but in many cases has been found effectual in relieving the patient. With respect to venesection, however, as different opinions are entertained of its utility by different physicians, it may not be improper to offer a few remarks.
There was a period, during which blood-letting was in very general use, and obtained great credit, as one of the most effectual means of prolonging life: while a plethoric habit was supposed to be a principal cause of early dissolution. Through the veins thus regularly opened, at certain seasons, the superfluous or vitiated blood was emitted, while that of a more salubrious quality was supposed to be left behind. It is now well known, however, that the corrupted part of the blood cannot be separated from the mass, so as to preserve the remaining particles sound and uncorrupted. If the quality of the blood ever become vitiated and diseased; if it be too thick and viscous, or too acrid and serous, the whole mass necessarily participates in the infection; neither is it in the power of art to contrive any method, by which the corrupted part may be separated from that which is in a sound state. It would be equally unreasonable to expect, that a spoiled cask of wine could be cured of its tartness, by attempting to draw the acid and impure portion from the top, in order to leave the sweet and wholesome part behind.
Considered as a remedy, phlebotomy must certainly be allowed to possess its uses; it is sometimes a necessary expedient, to produce an immediate diminution of the fulness of the blood, particularly when the time is too short, and the danger too pressing, to admit
