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Show 0f the Ear. 932 11.I1.F.:,rt. 'l he iuttrnal Nzrele of 1h: La; Book Ill. 0f the Ear. TheMu/mlu: interim: is lodged in the. 0r rPetrofftm', and borroweth its beginning, where the 'Procefliir @etrofmts in coniunéhon With the 018115;. amides, and is branched With a double Tendon hinto. the Shorter Procefs and Neck of the Malleulur, fo that this Mufcle being inferred into it, draWeth where it is affixed to the 1mm. Lindzznur calleth this Bone Caclear, ofwhich Icannot imagine the reafon, feeing itis of a round lhape,_and not like a it inward, and forward with the Membrane of the Tympamtm affixed to , difcovcrable. Having given a defcription of thefe fine finallBones, lodged in the 73%:Mum, I will make bold to give an account oftheir Origination too. In the Fifth Month of the Emu, in the inward Region of the 0x Tetra- this Mufcle 3 whereupon this Membrane is Ftiffned by the various conttaai. ons of the outward and inward Mnfcle, as Two Antagonifis 5 The Fitll Mufcle drawgth outward and upward, and the other draweth it inward and forward, whence thefc contrary outward and inward motions do b3. lance each other, and by bracing the Membrane, do render it Tenle, and fit to entertain the Appulfes of Sounds. The Bony circle being firipped off and the Membrane firmly adhering to The Tammnizm ol the Eat, The Bones of ll'lC Ear. f T. n F ,1.ll. at Furl? che ol'the Ear. Thefe Three curious Bones, appear affixed to the finnmmm, the Mullen: tirade by many Proceifes and 81'an. . lnthis Cavity may be difcovered Four Bones (del'ntute of any 'Prriafli. um, mutually conjoyned by the mediation of l, 1gaments, ) Mal/em, Incm, Super, and ()r Orbitulnrc, which are little in quantity, but greatin uk, and various in Figure in all Animals: A Coofe hath only Two, a Mal/col)", and an oblong Stupor, or rather an Inn», whofe lhape refembleth in Figure the Balis ofthe Super. The Mallcur 'l- is feated within the Membrane of the Tympwmm in the upper and hinder part of the Bony Circle; and is furnilhed with a round Head, to which a fmaller part is appendant, in fome manner refemblingz care in its outward Surface, and Convexe in its inward. The Otigcr. of the Bone: of the Eon is gtiflley ; The Bale of the Super, and both its Shanks are turned Bony, refumbling rather in its upper Region the Segments of a Circle, then an Ifocelfl, with which it is enducd, when it arriveth to more perfection, and its ultimate Figure. The Fourth Bone of the Tympannm, fiyled 0r Orbiculare, being a; round fmall Bone, firll difcovered by Learned Syloim, and may be feen in a boiled Calves Head 9 but cannot (faith curious Kerkingmr) be found in the Ear of a Fetus. in the Fifth and Sixth Months, the Mal/em Im‘IIJ‘, and Shape: are fully accornplifhed in their Figure, and partly in their fubliance As to the ufe of the fine Bones lodged in the 0: Petra/um, I conceive one may be this, That they being feared near the Membrane of the fimpgnum, may guard its tender Contexture againft the violent morion of the Ambient, or inward Air, by preferving it in its proper fituation, lefi it lhould be obnoxious to Laceration, as too much extended. Whereupon the Membrane ‘ of the Tympaimm leaneth upon the Mal/em, according to its inward Surface, This Bone in its oblong Head, is loofely articulated, with the luau, and in its Stalk or Termination is flrongly fal'tned to the Membrane of the 73miumrm, to guard it againfl the too too impetuous Appulfes of Air. And to fecure the Malleur in its proper fituation, Nature hath formed an- to which it is faliened to detain it in its due place, without violation: The Mallvm is alfo aflilled with the Incur and Stripe!) as Auxiliaries to it, in order to the prefervation of the Tunicle of the Tympammz, againli the incurfion of inward Air, as CaflEriur 'Placemimu will have it. Ait ille, lib. 4. Cap. 9. other Bone, called Imus 'l- framed above, of a broad, thick, and unequal 'Pag. 260 Qymdo agitation at impulfu Aer}! interni Tympzmum, (7 Mullen: extrorfitmagumur, [rims egrqflum Mallei, cui per gingljmrm Curriculum eff, dam part, and protuberant forward, and in its upper Region containcth 2! SW". 1 adapted to the reception of the Malleolur : Bur in the lower Region the 1m: cmitteth two long, flender, acute Proceffes,fomewhat difiant from each othCIi a: Dréirflllfl, or Fourth in its Cone to the 0: Squammofum : The Second is decked with an Oval Fi- gure, and is feparated from the other by the interpolition ofa Cartilage: The Third is fo little, that it exceeds not a Pins-head in dimenlions. in its larger part is rendred Bony, while the longer Procefs remaineth Cartilaginous; and then‘thc luau groweth all Bony, except its extremity, which Proceifes, the one is lhort, into which is inferred the inward Mufcle of the Ear, but the other Procefs is more long and (lender, which refleth upon the Orbire of the Tympammz. The. other Procefs of the Malleur, fome Anatoni ifts compare to a Stalk, or Tail, which crooking it felf inward, rendreth the Membrane of the Tympanum (to which it is fafined) fomewhatCon- $1111.54." The Itzpu. or Third Bone orthc Ear- fltm, are formed Three fmall Bones, the one refetnbling a Pear, is joyned modern Anatomifis Bmpdmlm, whofe inward furface is rough and unequal, Neck : And fomewhat further in the middle, this Bone is adorned with Two i7 .2. [,4 I. laws, or St:ond hunt, Spoon ofa Concave Surface on one frde, and a. Convex on the Other; he alfo afligneth it Three Procefles, which are f0 fmall, that they are fcarce it, a large Cavity prefenteth it fclf,called by the Antients Antrum, and by the 'l he Mali: us, ne. Book Ill. the one being fhorter, leaneth upon the hinder part of the Cavity of {he Tympanum ; the other more long Procefs, bath a fuperlicial Cavity, to Wlmh the head of the Staper is loofely conjoyned by a flrong Ligament. The Sniper is the fmallefi of the Three Bones 5 in Beafis it is endued with l a triangular Figure, like a A; But in Men its little round head ( is annexed above to the 1mm) from which are derived two fmall Shanks or Procellfiy hollowed like Arches, fupported by a thin porous tranfverfe Bafc, which doll! clofe the Faramm Ont/ale, by reafon the Bafe of the Staper, doth anfwcf 1‘ in Figure and circumference, to which it is fafiened with a 1009: lento"s Ligament 5 f0 that it may be with eafe drawn inward, but not lifth "l" or put outward without offering a violence to it. TheFourth Bone called 01- Orbiculare, is minute and round, whence it i hath its determination, and is tied with a Ligament to the fide of the SW"! , whcrc ddprj'finitam perwenit metam, termilmt. Cretemm in ca mom Ivfalleu: r(xix/id: yam em comprimit: nude [mt duabws apop/ayjibur, tanqrmm fulcri: donate Efii alien; Ofl; (Petroflgwerfu: mafloeider antmm, annitente, altem [origin/mid Stapedi! act's perbellc ac clegamer firmam. In the middle of the Cavity, relating to the 'ijzpanum may be difco- *- 7mm; 5‘ _ _ . _ The higher vered Two holes, the higher is adorned With an Oval Figure 1', and rsclo- holwm-c Tmpanm. fed before by the Bafe of the Stapu -, and in its hinder part hath an AP-erturc into the Labarintbm. The other hole is lefs, and feated lower, and being endued with a. round The lower hole of it. "MP6 'l‘ always keepeth open, as having no covering, and is divided into l"""""" wo Channels (by the mediation of a Bony Scale) of which one tendeth to‘- Ward the Carlee, and the other toward the Labarinthm. The Labarintbu: 1- is much lefs in Dimenfi'ons then the Tympanum, and hfc'iiiiiiiib receiveth this denomination, upon the account of many femi-circles (clothed rim of m with a fine Membrane) returning by diverfe Maanders into the fame Cavity, '1‘" into |