Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/752

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filling the lower part of the lateral concavity in the os calcis, is chiefly inferted in the contiguous angle of the OS cuboides. The captular ligaments agree with thofe of the aftragalus. The os fcaphoides is tied to the os cuboides on its outfide by one ligament, which connects it to the contiguous angle of that bone: on its upper part two go from it to the fecond and third offa cuneiformia; on its anterior fide it is joined to the Convex fide of the great os cuneiforme by two ligaments, and on its lower, it has four ; the firft appears double, and goes from the tuberofity of this bone to the bafis of the firft os cuneiforme, the fecond and third go obliquely to the fecond and third os cuneiforme, and the fourth is a little tranfverfe, being fixed in the inferior internal angle of the os cuboides. The os cuboides, befide thofc already defcribed, has ligaments which tie it above, below, and on the outfide with the third os cuneiforme, and the two laft bones of the metatarfus ; the fuperior ligaments are almoft equally flat, the inferior irregu- larly thick and ftronger than the fuperior. The three ofla cuneiformia are connected together on their upper part by particular ligamentary planes, which go more or lefs tranf- verfely, from one bone to another, being all joined to one common ligamentary plane which covers thefe three bones ; and alfo to the os cuboides, they are alfo connected by liga- ments to the three firft bones of the metatarfus. The bones of the metatarfus are connected together by their bafes, and heads, the ligaments which go between the bafes are fuperior and inferior. The fuperior fmall and flat, the in- ferior, ffrong and thick ; thofe between their heads have near- ly the fame difpofition, but the inferior have this peculiar to them, that by filling up the fpaces between the head.', they keep them at fome diftance from one another ; the inferior portions are fixed in the angles at the lower part of each head, and are ftrengthned by their union and intexture with the apo- neurofis plantaris. IPinjkw's Anatomy, p. 134.

Bathing of the Feet. See Pediluvium.

Fractures of the Feet. The bones of the foot which compofe the tarfus, the metatarfus and toes, are equally liable to frac- tures with the other bones, but by reafon of the great com- plication of nerves, tendons, ligaments and membranes, frac- tures in this part are ufually attended with very bad fymptoms. The bones are carefully to be replaced and fecured by bandage ; but fractures of the/«r, like thofe of the hands can feldom be fo perfectly cured, 3s not to leave a ftiffhefs or want of motion behind ; if the patient fhould be fo happy as to eTcape ulcers, caries, or incurable fiftulae. Thefe bad fymptoms when they appear in the courfe of the cure, are no way to be remedied, but by the amputation of the limb, nor will that indeed al- ways fecure the patient from death. Hei/ler, p. 138. Dr. Waltherus has given a minute defcription of the mufcles and ligaments of the fole of the foot, in the Nova Aft. Eru- dit. Lipf. April 1732.

Foot, in meafuring — In 'Scotland, this meafure of length, the' confifting of twelve inches, exceeds the Englifh foot, fo that 185 of the former is equal to 186 of the latter. Treat. Pracf. Geom. p. 4. See Measure, Cyel.

Foot, in the manege, is the extremity of a horfe's leg, from the cronct to the lower part of the hoof. The font feet ate dif- tinguifhed by four different names: the two fore _/irf are by fome called the hands of a horfe; but that term is in difufe, the common expreflion being the far fire foot, to denote the right foot before ; and the near fore foot, the fiirrup foot, and the bridle-hand foot, to denote the left foot before. Of the two hinder/«r, the right is called the far hinder foot ; and when fpears were ufe, 'twas called the fpear foot, becaufe in retting the fpear, the focket of it anfwered the right hinder foot. The left-hind-yW, is called the near foot behind.

FooT-elerobe, in the manege. A horfe's foot has this appellation when it is worn and wafted by going without fhoes, fo that for want of hoof, it is a hard matter to fhoe him. A horfe's foot is faid to be worn and wafted, called in French use, when he has but little hoof, and not enough for {hoeing.

To gallop upon a good Foot, or put a horfe upon a good foot, called in French fur le bon pied. Scefa/fe Gallop.

Fat Foot, in the manege. A horfe is faid to have a fat foot, when the hoof is fo thin and weak, that unlefs the nails be driven very fhort, he runs the rifque of being pricked in {hoeing. The Englifh. horfes are very fubjefl to this diforder.

Foot is alfo ufed for the foot foldiers, or the infantry of an army. See Battle.

Foot- hooks, inafhip, fee Futtocks.

FORAMEN {Cjcl.)— Foramen auditorium internum, in ana- tomy, is fituate in the backfide of the apophyfis petrofa, in fome meafure behind the veftibulum and bafis of the cochlea. It is a kind of blind hole divided int.) two foffula, one Iar^e, the other fmall ; the large one lies loweft, and ferves for the portio mollis of the auditory nerve, or feventh pair; the fmall one is uppermoft, and is the opening of a fmall duct, thro' which ihe portio dura of the fame nerve paffes. The inferior foffula is full of little holes, which in the natural flate are filled with nprvous filaments of the portio mollis, which go to the fpindle, to the femicircular canals, and to thofe of the cochlea. It is thisfofliila which forms that (hallow cavity at the bafis of

the fpindle of the cochlea. The pafliige of the portio dura »f the auditory nerve runs behind the tympanum, and its orifice is the ftylomafloide hole. Fallopius gave this duit the name of the aquedufl, from its refemblance to the aqueducts in Italy. It begins by the fmall foffula, and pierces from within outwards', the upper part of the apophyfis petrofa, making there an an- gle or curvature ; from thence it is inclined backward behind the fmall pyramid of the tympanum, and runs down to tie ftylomafloide hole, thro' which it goes out. It communi- cates likewife by a fmall hole with the finus of the pyramid, and lower down by another hole with the barrel of the ear! In fome fculls this aquedufl of Fallopius is open on the upper part of the apophyfis petrofa, a kind of break appearing in it, formed by a double hole. It is at this place that it makes tin- angle already mentioned, but it is commonly covered with a bony lamina. If'injhw's Anat. p. 5?.. Foramen ovale. — The anatomical difcoveries of the feveral parts and their conftruaions, does not always bring with them the certain knowledge of the ufes of thofe parts The heart, the arteries, and the veins of the human body, have been known for many ages ; yet the ufes of thefe feveral parts for the circulation ot the blood was referved for a later disco- very. The circulation of the blood in the foetus is a thing yet not perfeflly underftood, nor are we well affiired, whe- ther it paffes in the heart from right to left, or from left to right, or whether by means of the foramen ovale, it may not pafs at once in both thofe directions.

The different method of the circulation of the blood in adults and in the foetus in the uterus, is owing to the different con- ftruflion of certain parts. We very well know lhat in adults the blood going out from the right ventricle of the heart' is carried by the great artery and the two pulmonary branches^ throughout the whole extent of the lungs, and thence by the pulmonaty veins is returned into the auricles, and left ventri- cle of the heart, from whence it is diftributed throughout every part of the body, thro' other arteries, and is returned thence to the heart again by other veins, into the right ventricle, to continue this certain courfe, during the life of the animal. The courfe of the blood thro' the heart funpofes therefore two circulations, the one a fmaller and fhorter courfe of all the mafs of blood from the heart to the lungs, and thence to the heart back again. The other a much greater, and by a much longer courfe, by which the whole mafs of blood parling out of the left ventricle of the heart is diftributed by numbers of veffels into every part of the body for the nourilhment and increafe of the parts, without excepting any part of the hu- man frame, and returns thence into the right ventricle, to be thence fent into the lungs again. Memoirs Acad. Scien. Par. 1739. See Circulation.

Tho' this is however the cafe in adults, it is far otherwife in regard to the circulation in the foetus ; for befide the placenta the umbilical veffels and the venal canal, which are peculiar to the animal in that ftate, the (eptum which divides the two au- ricles of the heart, is at this time perforated by an apetture which is called the foramen male ; and the trunk of the pul • monary artery a little after it has paffed out of the heart, gives rife to a canal called the arterial canal, or canal of communi- cation, which terminates in and difcharges the blood which paffes into it into the defcendant aorta.

As foon as the foetus is born, the foramen begins to fhut, and by degrees becomes wholly clofcd, and the arterial canal dries up and degenerates into a mere ligament. Anatomy informs us, that in adults, the blood which paffes thitf the pulmonary artery, in order to its being diftributed thro' the lungs, does not make that circuit on account of the lungs, but merely on its own account, that is to fay, to be it- felf altered by the change the air we refpire is capable of making in it ; for the lungs themfelves are in reality nourifhed by that blood which is derived into them by means of the bronchial artery.

As the foetus therefore while it remains in the womb does not refpire, it would be a wholly ufelefs circuit for the blood in that ftate of the body, to make this fhorter pafiVe of the whole mafs thro' the lungs, as it does in adults, before It ar- rives at the left ventricle, and is thence diftributed throughout the whole body ; and as the blood would in this ftate of the the animal, make a needlels and a ufelefs paffage thro' the lungs, fo would it alfo, while making that circuit, be wanted in thofe parts, to whofe nourifhment and growth it is extreme- ly wanted ; and what afterwards determines the blood to take the citcuit of thefe parts and to drive itfelf into them with all poffible fpeed, is a feries of neceffary confequences which hap- pen at that time.

When we confider what it is that happens to a foetus at its coming forth from the womb, and that it at that time firft refpues, jt is eafy to conceive that this new afiion of refpiration, cannot but neceflanly hurry the blood toward the lungs, and that the extenfion which the infpired aerial particles make in the lungs, gives place to a much larger quantity of blood than before, to fill the veffels there ; and confequently in that in- aflive ftate in which the lungs in the fcetus are continually placed, before it has ever yet refpired, we may conclude, that

the