Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/776

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GAL

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'■fcUt from thofc ulcers, yet he lived and continued bride after doing this every day for three months. But on injecting the folution of the hile in the fame manner into the crural vein, he died on the fourth day with a large bubo on the wounded thigh, on which alfo there were two carbuncles and a gan- green'd part;

The bile being collected after this from one of the dogs dead of the plague, and in the fame manner diluted with water, and injected into the crural vein of another dog, the creature was immediately convulfed, a carbuncle appeared on the breaft the fecond day, and the day afterwards the dog died with a bubo under his fhoulder. The bile taken from this dof, was in the fame manner injected into a third dog, and be died in the fame manner. Philof. Tranf. N°. 170. If half an ounce of alum in powder be added to a pound of ox gall, and the whole ftirred a little together, there rifes im- mediately an ebullition with a couliderable effervefcence, and the whole becomes thick and turbid like dung, and of a greeniih yellow colour j but after awhile, the gall will be precipitated, and its thicker parts feparating themfelves and 'falling to the bottom, the remainder will become of a clear hue and a redifh colour.

After this has Mood five or fix days, feparate the clear liquor from the feces at bottom, and from what fouluefs fwims at the top, and fet it in the fun for three or four months in a vial well flopped ; there will at the end of this time be found another precipitate at the bottom of the vial, and on the furfacc of the liquor, there will gradually gather together a white and hard fatty matter, and the red colour of the liquor finally will change into its primitive yellow again ; and what is very remarkable, the whole will have the fmell of boiled crayfifh.

The obfervation that there is contained in this red liquor of the gall, though fcemingly perfectly clear, a white fatty mat- ter like fuet, and that on the feparating of this white matter, the red liquor lofes its colour, and regains its primitive yellow together, prove that the fubftance naturally contained in the £a// bladder, is a kind of liquid foap. We very well know that the foap we ufe is no other than oil, or other fatty fub- Itances united by boiling to the alkaline fait called pot afhes. In the colder countries where thefe ingredients are more fcarce, they fubftitute the fat of animals for oil, and common allies for the alkali ; and the foap is as good for all the purpofes as the other. In the conftituting the gall, nature has ufed a folid ani- mal fat, and inftead of a fixed alkali, me has employed that com- mon volatile one with which all the parts of animal bodies a- bound : in this operation this fat has been feen to feparate its felf by little and little, and as it amaffed itfclf together, to appear in its native form white and hard like the fat of animals ; and the eaufe of this reparation has been the defiroying the alkali by means of the acid of alum, the fat having feparated itfelf on that admixture in the fame manner, as the fatty part of our com- mon foap does on the mixing any acid with it. The liquor of the gall appears red after its firft precipitation, and lofes this colour again by degrees as the fat becomes fepa- rated from it ; the reafon of this is, that almoft all folutions of oily or fatty bodies are red, be the menftruum what it will, and this being one of thofe folutions mull be red fo long, as it continues fuch* that is, fo long as the fat remains fufpended in it ; but as foon as- that fat is feparated, the cauls of the red colour ceafes, and the liquor becomes yellow. This depurated liquor of gall, is one of the greater!: of all re- medies for freckles in the face : the manner of ufing it is this, mix together equal parts of it, and of oil of tartar per deli- quium, to a dram and a half of each of thefe, add an ounce of river water, mix them well by making, and keep them in a viol well flopped : the end of the finger being wetted with this, is to be touched upon the freckled part, and this repeated three or four times a day letting it dry on, at length the part will look red, and there will be a fort of tickling fenfation felt in it ; and after that, the fkin will become fcurfy and both that and the freckles will fall off. If this does not fuc- ceed the firfr. time, it is to be repeated, and it will clear the face for fix or eight months, at the end of which time it is to be ufed again. "Mem. Acad. Par. 1709.

Gall bladder. Mr. Petit, gives us the marks by which a diftention of the gall bladder from the bile, making an exter- nal tumor with fluctuation, may be known and diitinguiihed from an abfeefs in the liver. See Mem. de l'Acad, de Chirurg. Tom. l. &Med. Eff. Edinb. Abr. Vol. 2. p. 491.

Gall is alfo ufed by naturalifts to exprefs any protuberance, or diftortion of a part of a leaf, or ffalk on a tree, or plant, occafioned by an infect living and growing within it. Thefe are all mon- ftrous and unnatural productions of the vegetables that bear them ; but they often are fo regular in their formation, that they have the appearance of fruits and flowers. On exa- mination however it will always appear, that they are fruits containing no feed, and flowers the product of which is ani- mals. Among the fmallcr infects, there are many which either in their whole ftate of the worm, or in a part of it, are of fo tender and delicate a ftructure, that they cannot bear the conta6t of the air ; and others that are continually expofed to the ravage of a number of deflroyers ; fo that by one or other of thefe means they could never live to arrire at matu- 4

rityi or to propagate their feveral fpecies. Provident nature has therefore allotted for the habitation of thefe, the. galls of trees and plants ; they never however find excrefcences rea- dy formed, but by their own action make them for them- felves. Some of thefe infects are produced from eggs laid by the parent animal on the ftalks of leaves or plants, and as foon as ever they ate hatched from thefe, make their way into the leaf, or ftalk, and find a fafe lodging in this recefs, and ne- ceffary food in its juices ; others are lodged even in the e^g ftate within the fubftance of the leaves and branches, and have no occafion for eating their own Way in. The parents of thefe are a peculiar race of flies, which have at their tail an inftru- ment prepared for this purpofe ; with this they pierce the fur- faces of vegetables, and lay their eggs in the holes they have made; fo that the worms hatched from thefe have nothing to do, but to gnaw the tender fibres of the vegetable, and feed on the juices extravafated from the apertures they make in them. Reaumur, Hift. Inf. Vol. 6. p. 176. *

The pucerons make their way into the leaves and tender parts of the branches of trees, and form a fort of galls, depofiting their young in the place where they are. Thefe are tender galls, by fome called bladders, which often crow to a very confiderable iize on the leaves of trees ; and were never well known or understood, till Mr. Reaumur explained their nature; The worms of fome flies, and fome fpecies 1 of fmall caterpillars, live alfo within the fubftance of leaves, and feed in great fafety and comfort to themfelves ; but thefe are continually changing place, and deffroy the part they feed in ; on the contrary, the worms which inhabit the common galls, never move out of the place where their parent depofited the egg, but there eat and fuck their nourifh- ment. This is fo far from deftroying, or injuring the part of the plant, that their feeding occafions a new derivation of juices to it, and it always grows larger and ftronger in proportion, as the creature eats within.

The galls caufed by different infects have a very different in- ternal ftructure, fome" of them have only one large cavity within, in which a number of the animals live in community,' others have feveral fmall cavities with communications between each, and others have different numbers of little cellules each feparate, and having no communication with the others : there are fometimes a hundred of thefe cellules in one gallj fometimes only two or three ; and finally, there are others' in which there is only one cavity inhabited by one infect:. The creatures of thefe two laft kinds, live in perfect folitude during the worm ftate, and can have no knowledge of any other living creature befides themfelves, till they have paffed through the intermediate ftate of chryfalis, and become winged animals like thofe to which they owed their origin, and are ready to lay eggs themfelves. The general divifion of galls into thefe clafles, admits of a vafl number of fubdiftincti- ons under each, from the different figure and confiftence of the feveral fpecies. Some of them are fo hard,- that they equal, or exceed the hardnefs of the wood of the tree they grow upon ; and when cut, appear cempofed of fibres, much more denfely and elofely arranged : Others are foft and fpongy, and refemble fome of the tender fruits in appearance* The nrft kind are ufually called gall nuts, and the latter apple galls, or berry galls. The common galls ulcd in dying, are of the firft kind, and what are called oak apples, and oak grapes are of the latter. The oak produces feveral of this laft fpecies of galls, fome of which are oblong, and others round refembling grapes, goofeberries, and other frujts ; thefe are alfo ufually beautifully coloured, fome being of a bright red, others of a bright yellow. Thefe galls of the oak, are of the auftere tafte of the juices of that tree j but thofe of other plants, are often well tailed. There is a fpecies of fasje, well known by the name of apple fage, the leaves of which af- ford a lodging to the worm of a peculiar fpecies of fly, and this gall grows to a very confideiable fize, fo as to have obtained the name of an apple from its refemblance to this fruit ; thefe are eaten by the people of the eaftern nations, and are com- monly fold in the markets of Conftantinople, and other places. A plant very common with us, the ground ivy, lias the fame pro- perty : its leaves are often loaded with galls on their underfide, which are very green and juicy, and of no diiagreeable tafte. Mr. Reaumur gives us an account of their being one year fd plentiful in the neighbourhood of Paris, that the poor peo- ple eat them both raw and boiled as food. See Tab. of In- fects, N 3 25, feq. Reaumur, Hift. Inf. Vol. 6. p. 182. The round galls are by far the moft numerous clafs of all others; but thefe have great differences in their appearance : fome are perfectly fmooth on the furfacc; others are very rough and knobby ; fome adhere immediately to the leaf or ftalk of the vegatable ; and finally others are placed on a longer ■ or fhorter pedicle.

There are however, other very Angular figures among the galls, and of thefe fome are fo ftrangely irregular, that it is very difficult to conceive to what mechanifm they owed them. Among the feveral fpecies, there are fome which feem to be only the part tumified on which they are placed : thefe re- femble varixes of the veins in animals, and are therefore by authors called varicous galls. The leaves of the willow, and fome other trees afford us a vaft number of the mils of this

kind ;