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Part I. i6o A N A T O M Y. The o/Ta nafi are placed at the upper part of the nofe; on their inner edge, where they are fuflained by the fep—the olTa unguis are at the internal canthi of the orbits; tum narium. Their pofterior fide, at its upper half,
—o)Ta malarum form the prominence of the cheeks ;—of- has externally a depreffion, where it is overlopped fome fa biaxillaria form the fide of the nbfe, with the whole way by the maxillary bones, while its lower half covers lower and fore part of the upper jaw, and the greatell thefe bones: By which contrivance, they do not yield fhare of tire roof of the mouth ;—ofla palati are (ituated eafily to preflure applied to their fore-part or fides. at the back-part of the palate, noftrils, and orbit;— A- fmall hole is frequently to be obferved on their exofla fpongiofa are feen in the lower part of the nares ;— ternal furface, into which two, three, or four holes, which appear internally, terminate for the tranfmiflioij and the vomer helps to feparate thefe two cavities. The bones of the upper jaw are joined to the bones of fmali veins; fometimes the holes go no further than of the fltulLby the fchindylefis and futures already de- the cancelli of the bones. fcribed as common to the cranium and face, and they are The nafal bones are firm and folid, with very few cells cancelli in them. connedted to each other by gomphofis and fifteen fu- or They are joined above to the frontal bone, by the tures. The gomphofis only is where the teeth are fixed in middle of the tranfverfe future ;—behindv to the maxiltheir fockets, and the fchindylefis is only, where the edges lary bones, by the lateral nafal futures ;—below, to the cartilages of the nofe;—before to one another, by the of the vomer are joined to other- bones. The firfl: is the anterior nafal, which is ftreight, anterior nafal future ;—internally, to the feptum narium.' and placed longitudinally in the middle fore-part of the Thefe bones ferve to cover and defend the root of the nofe. Bpfe. The fcconb and third are the lateral nafal, which are Ossa Unguis, or Lacrymalia, are fo named, beat each fide of the nofe, and almofl: parallel to the firfl: caufe their figure and magnitude are fomething near to thofe of a nail of one’s fingure, and becaufe the tears pafs future. Each of the two lacrymal is almofl: femicircular, and upon them into the nofe. Their external furface is compofed of two fmooth conis placed round the lacrymal •groove. The fixth and feventh are the internal orbitar: each cavities and a mid 1? ridge. The depreffion behind of which is extended obliquely from the middle of the forms a fmall fhare of the orbit for the eye-ball to move on, and the one before is a deep perpendicular canal, or lower fide of an orbit to the edge of its bafe. The two external orbitars are continued, each from fofla, larger above than below, containing part of the lathe end of the internal orbitar, to the under and fore- crymal fac and duCl. This is the part that ought to be pierced in the great operation for the fiftula lacrymalis. part of the cheek. The tenth is the myjlachial, which reaches only from —This fofla of the bone is cribriform, or has a great the lower part of the feptura narium to between the two number of fmall holes through it, that the filaments from the membrane which lines it, infinuating themfelves middle dentes incifores. The longitudinal palate future flretches from the into thefe holes, might prevent a feparation of the memmiddle of the foremoft teeth through the middle of all brane, and fecure the bone in its natural fituation. The ridge between thefe two cavities of the os unguis, is the the palate. The tranfverfe palate one runs acrofs the palate, near- proper boundary of the orbit at its internal canthus ; and beyond which-furgeons fhould not proceed backwards in er the back than the fore-part of it. Each of the two falato-ntaxillary is at the back-part performing operations here. The internal or pofterior furface of this bone confifts of a furrow in the middle of of the fide of each noftril. The fifteenth is the fpinous, which is in the middle of two convexities. the lower part of the noftrils. This may perhaps be The fubftance of the os unguis is as thin as paper, and very brittle ; which is the reafon that thofe bones rather thought a double fchindylefis. Thefe futures of the face have not fuch confpicuous are often wanting in fkeletons, and need little force to pierce them in living fubjects. indentations as thofe of the fkull have. Ossa Nasi, fo named from their fituation at the root Each of thefe bones is joined, above, to the frontal of the nofe, are each of an irregular oblong fquare figure, bone, by part of the tranfverfe future;—behind, to the being broadeft at their lower end, narroweft a little os planum of the ethmoid bone, by the fame future;—. higher than their middle; and becoming fomewhat larger before, and below, to the maxillary bone, by the lacry-' at the top, where they are ragged and thickeft, and have mal future;—internally, the ofla unguis cover fome of a curvature forwards, that their connexion with the fron- the finus ethmoidales. tal bone might be ftronger. Thefe bones are convex Thefe unguiform bones cofnpofe the anterior internal externally, and thereby better refill: any violence from parts of the orbits, lodge a fhare of the lacrymal fac and without; and they are concave internally, for enlarging duft, and cover the eithmoid cells.-——Their fituation and tender fubftance make a rafh operator in danger of the cavity of the nofe. The lower edge of thefe bones is unequal, and is deftroying a confiderable fiiare of the organ of fmelling, ftretched outwards and backwards, to join the cartilages when he is performing the -operation of the fiftula lacryof the noftrils.—Their anterior fide is thick, efpecially malis. above, and unequal, that their conjunction to each other Ossa Malarum are the prominent fquare bones might be ftronger; and a final! rifing may be remarked' which form the cheek on each fide, Before, their fur- ‘ -face
