Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/99

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(borten or contract themfelves in one particular direaion j wherefore the parts compofed of thefe fibres arc very properly compared to the Mufchs of animals. By the word Mnjcie we underftand a part compofed of fibres fo determinate^ ar- ranged, that by their contraction they can only move the part in fome certain and determinate manner; and in this which feems the received fenfe of the word, there are many inftances in which it may be ufed to parts of plants, with the itrifteft

jufticc. ,, , , ,.

All the pods of the leguminous plants, as peaie, tsc. are compofed each of two valves, more or lefs convex on the out- fide ■ thefe are placed evenly upon one another, and fattened together by means of a great number of very fine veflels ; they are fa'ftned much more firmly together at the back, than at the fore-rim ; and the large veflels which carry nourifhment both to the valves and feeds, are lodged there, and fend many ramifications both to one and the other of the valves of the

pod. s _ >p

Each valve is formed of two ranges of fibres ; the exterior arrangement is formed into a fort of net- work, and the threads which compofe it iflue from the back of the pod, and are propagated longitudinally and fomewhat obliquely through the furface of the valves, and finally terminate at the edge or fore-rim of the pod, after they have entered into the flefhy part, with the net-like plexus of veflels, of which they make frequent anaftomoies.

The interior plan or arrangement of fibres croffes the exte- rior, in the fame manner as the interior intercoftal Mufcks in the human body crofs the exterior ; and thefe form the in- ner membrane of the pod : Thefe fibres arife like the others from the back of the pod, and run obliquely to the edge. A neceflary confequence of this ftructure is, that the arrange- ment of exterior fibres muft become dry before the others, as tnuft alfo the fiefhy fubftance in which they lie ; and the confe- quence of this is, that they muft contract and draw the edge of the valve to which they belong at once upward and out- ward, and endeavour to feparate it from the edge of the other valve, drawing with it the interior arrangement of fibres ; this therefore pulls open the pod, and the air which is very hot at the fea(on when the feeds of thefe plants ripen, infmu- ating itfelf into the interftices of the internal arrangement of fibres which are expofed to j't by the opening or the pod, foon acts upon them, and they begin to contract in their turn. Thefe fibres were once the veflels which con- veyed the nutritive juices to the pods and feeds ; but when that ufe is no longer neceflary for them, arid when no more juices afcend, after the feeds have arrived at their deftined iize, they then fhrink up, and no more perform the office of veflels, but become mere fibres. As theie do not all dvy up, and fuffer this change together, but neceffarily it happens firft to thofe which are fituated at the greateft diftance from the pedicle, and confequently thofe are the firft of the interior fibres which act by fhortening themfelves ; this therefore be- gins at the extremity of the pod, and is continued up to the pedicle,' and the effect is that as thefe interior fibres are ilronger and more numerous than the exterior, which arc at this time as far fhortned as they are capable of, they now draw back- wards and inwards the lips of the edge of the pod toward the back. When the warm air acts upon thefe fibres to dry and contract them, it draws nearly equally at both their ends ; and therefore if the two arrangements of fibres were regu- larly tranfverfe, each valve of the pod muft be drawn by this action into a fort of tube, or pipe ; but as they are placed in an oblique direction, and parallel to one another, the natural effect of their contraction muft be the drawing the valve into a fpiral form, which we fee is exactly the cafe. The lines which form the rim of each valve can make no refiftance to this contraction, becaufe they are fo dried up by the warm air, and want of juices, that they may be crumbled to pow- der between the fingers, and cafily break in any part with the fmalleft force. This clafs of plants gives numerous inftances of this fort of Mufcks in vegetables, and they are more obvi- ous than moll others, being not only common in the hedges but cultivated in gardens for tiie ufes of the kitchen, &c. The ingenious author of the fyftem gives many other inftances in other plants. Mem. Acad'. Par. 1693. Muscle, in ichthyology, the Englifh name of the Mytulus.

See the article Mvtulus. Horfe-Mv$CLE. Sec the article Ho-RSE-Muftk. MUSCULUS (Cycl.)— Musculi capitis accejfbni. There is fometimesfaundamiaU jj/u/c/ffixed by one end to the extremity of the firft tranfverfe apophyfis of the neck near the infertions of the two cbliqui, from whence running up obliquely it is again inferted behind the maftoide apophyfis. This Mufcle is commonly thought to be a third final I tranfverfalis, on that fide where it is found ; but it feems rather to be an ad- ditional Mufclt to the obliquus fuperior. The recti, and other obliqut are alfo found fometimes double. WinflovJs Anat. p. 238. MuscULUs^/fo/rtd? kite, a finall and pretty long Mufcle fituated a little obliquely upward, and downward on the forepart of the hip. It Is fixed above to the outfide of the anterior fupe- rior fpine of the os ilium, between the infertions of the glu- teus medius, wdfartorius. From thence its. fiVfby fibres run SufPL. Vol.11.

M U S

down a little obliquely backward, forming a very flat body four fingers breadth in length, and two in breadth. This body lies between two lamina of the fajcia lata, and is in- ferted therein by fhort tendinous fibres, which difappear at that place where the fafcia adheres to the great trochanter, and tendon of the gluteus maximus. The fafcia is therefore by no means to be looked upon as a tendinous expanfion of this Mufcle. Win/lew's Anatomy, p. 2 1 1.

Musculus Lotus. See the article Latus Mufculm.

Musculus, is alfo a name by which fome call the common fea Mufcle, more properly called Mytulus. See the article Mv- tulus.

Musculus My/licatus, in ichthyology, a name given by Gefner and fome other writers, to the common whale or balcsna eden- tula of authors. This is diftinguifhed from all the other ce- taceous fifties by Artedi, by the name of the whale with the fiftule in the middle of the head, and with the back fharp to- ward the tail. See the article Baljena.

Musculus, among the Romans, a military machine, under cover of which the foldiers approached and undermined the walls of places befieged, of filled the ditches'. Pitifc. Lex. Antiq. in voc.

MUSCUS Jrborefcens MaHnui, m botany, a name given by Count Marfigli to a very elegant fpecies of fea-plant. It grows to the rocks at confiderable depths under water, and fs ufually of about three inches high ; and is compofed of feveral thick branches, ftirnifhed toward the tops with transpa- rent leaver. The ftalks are hollow, and it is all foft while in the fea, but grows fomewhat rigid when dried. When examined by the microfcopc, its furface appears to be granulated or covered with a fort of fmall glandules, which Hand very near one another, and on cutting it tranfverfely the whole fubftance is feen to he hollow, and that general hollow to communicate with all thefe glandules, fo that their office plainly is feverally to receive the fea-water, and convey it into this general cavity, where it is diftributed throughout the whole plant for its nourifhment and fupport. The leaves of this plant being rubbed on blue paper, give it a yellowifh green colour.

Count Marfigli has gone through the analyfis of this plant, and as by it we may be informed of the principles and pro- perties of many other fea-plants of the lame genus, it may not be improper to give an abftract of his observations. Four and twenty ounces of this plant being put into a retort, there came over five ounces of phlegm of a fweetifh tafte, and of the colour of oil of almonds. The fpirit was of a dufky earth colour, of a fixed nature, of an unctuous yet fome- what acrid taftc, and leaving a bkternefs behind it ; of this there was twelve ounces, and the remainder in the retort was fix ounces and three drams. So that the whole produce being twenty-three ounces and three drams, there was only five- drams of the whole loft in the operation. The water does not alter the colour of blue paper, on ftceping in it ; being mixed with the decoction of mallow flowers it turns it to an afh-colour. The decoction of galls becomes of a bluifh colour, and a folution of copperas of a greenifh afh-colour with it : The tincture of turnfol becomes of a bluifh colour, tending to white. Spirit of nitre being added to it caufes a flight fume, and the decoction of mallow flowers being after this added, a fine red colour is pro- duced. Spirit of vinegar turns this green ; and no change at all is produced by any of the following liquors, fpirit of fait, fpirit of fal armoniac, lime-water, alum-water, oil of tartar: a folution of corrofive fublimate collects a quantity of white and grofs particles, and precipitates them to the bottom. Mar- figli, Hift. delaMer. p. 73.

The fpirit being examined with blue paper makes no change in its colour on being fteeped in it ; the decoction of mallow flowers mixed with it becomes of a pale yellowifh green ; the decoction of galls changes with it to a dufky red ; a folution of copperas becomes of a dirty yellow, and thick; the tincture of turnfol changes to an afh-colour. Spirit of nitre being mixed with it, caufes a moderate fume without any ebulli- tion, and the colour of the mixture is a reddifh grey ; on mixing the decoction of mallow flowers with this, it becomes of a yellowifh red. Spirit of vinegar added, renders it more fluid and of a lefs dufky colour. Spirit of fait changes it to a reddifh colour. Spirit of fal armoniac, and oil of tartar, make no change at all ; but lime-water renders it more clear and fluid. Alum-water collects a quantity of white matter, and precipitates it ; and a folution of corrofive fublimate, in like manner turns it white, and precipitates the grofs parts. The caput mertuum yielded one dram and ten grains of fixed lixivial fait j the tafte of this is but moderately acrid, and its colour a greyifh white ; being rubbed on blue paper it changes its colour to its own. The decoction of mallows on mixing this fait with it lofes its blue colour, and becomes grey ; and on frequently fhaking the veffel, it finally becomes yellow. Spirit of nitre mixed with this fait does not fo readily or vio- lently effervefce with it, as with moft other lixivial falts ; and if a little turnfol be added to this, it becomes of the colour of red wine. Spirit of vinegar diflblves it very quickly, and becomes thick and turbid with it. Spirit of fait diflblves it very readily, but makes no fume, though a very confideiable 2 A ebullition.