I Doubt not in the least butThisand theproceeding Chapterwill seem needless, and appear superfluous to some Persons, in thePracticeofMIDWIFERY; namely, to such as know not theNew Improvementsof thisArt: But especially to such as are accustom’d to theUseofInstruments, they’ll appear altogetherUselessandVain; since suchPractitionerscan easily (uponany Occasion, without the curiousAnatomical Knowledgeofthese Parts) first slay theINFANT, and then eitherdeliverorkilltheWOMAN, asChancemaydirecttheirSHARPS.
BUTfor my Part, because I have no Notion of such sort ofWeapons, I shall endeavour to acquit my self morehonourably, and teach myFollowersanother way, andThatwithoutBlood-shed; as I hope will hereafter more amply appear.
ANDFirsttherefore in speaking of theBonesof thePELVIS, I shall begin with theOSSA Innominata; which aretwolargeBonesjoined to theSidesof theOS SACRUM.Theyare compos’d ofThreedistinctPieces, each of which has its respectiveName: TheFirstandsuperioris call’dOs Ilium; because theGutsIlialie upon it directly. It isLargeand almost of aSemicircular Figure, a littleConvexandUnevenon itsExternal Side; as it isConcaveandSmoothon theInternal. In short, it is join’d to theSidesof thethree SuperiorVertebræof theOs Sacrum, and isLargerinWOMENthan inMEN.
THESecondandAnterioris call’dOs Pubis; which is united in theForepartto itsFellow-BONEof theother Side, by an interveningCartilage: By the Extension of whichCartilage, theOssa PubisinYoung Women, sometimes recede a little fromOne another, to facilitate a difficultBirth.
THEThirdis theInferiourandPosteriour, call’dOs Ischium, orCoxendix, which has a largeCavitycall’dAcetabulum Coxendicis; and This receives theHeadof theOs Femoris; theSuperciliumorTopof whichCavityjoins theOs Pubis.
THESEThree Bones, until the Age ofPuberty, may be seen distinctly, tho’ afterwards they grow together, and becomeone BONE, without leaving any Mark ofDivision. They adhere on eachsideto theOs Sacrumbytwo Strong Ligaments; theUpperof which passes from thePosteriour Acute Processof theIschiumto theSacrum; as theLowerjoins theTuberculumIschiito theSacrum.
THESEBonesinWOMENare more distant or separated fromOne another, and aresmallerthan inMEN; especially theOs Pubis, to the end that theCavityof thePELVIS, and theAnglebetwixt theOs PubisandIschium, may be theLarger, for the more commodiousBearingof theInfant, and the more easyExclusionof it inBirth. But from hence I would no ways infer, that theOssa PubisandIliasever themselves in time ofLABOUR; (notwithstanding theOpinionofsome Authors) for I am fully satisfied of thecontrary: Because I have conducted more than oneWomanin my Time, upon walking out ofone Chamberintoanother, immediately afterDELIVERY; which could never have happen’d inCaseof such a distant or dislocatedSeparation.
THESEBonescall’dInnominataare of wonderfulUseandService: For besides that they form thePELVIS, and defend every Part of itsContents, they also giveConnexionandJunctureof the rest of the Body, to theThigh-Bones; as they likewise giveRiseandOriginto manyMuscles, and are theBasisof Support of theSpineof theBack, as well as of all theSuperior Parts. Whence I comeà proposto descant a little upon this particularPart, as far as concerns our present Purpose.
THESpinethen is thatBony ColumnorRidge, which extends itself down theBackfrom theHeadto theFundament, containing theSpinal Marrow, and resembling theLetterS in figure.
INThisSpinatherefore we must consider itsFivefold Division; namely, intoNeck,Back,Loins,Os Sacrum, andOs Coccygis. The FirstThreeconsist of 24Vertebræ; whereof theNeckhas 7, theBack12, and 5 belong to theLoins.Thoseof theNeckbendinwards; those of theBackoutwards, for enlarging theCavityof theThorax;Thoseof theLoinsbendinwardsagain; andThoseof theOs Sacrumoutwards, to enlarge theCavityof thePELVIS.
THEVertebræof thetwo lastconcern us most in this Place; wherefore I shall say no more of therest,save only by the By, or coincidently, as they fall in my way.Thoseof theLoinsthen are theThickestandBroadest, and theLastof them is theLargestof all theVertebræ; as theirCartilagesare thicker and stronger than any of theOthers, and theirAcute Processesare at a greaterDistancefrom one another. From whence it comes to pass, that the greatestMotionof theBackis perform’d by theVertebræof theLoins.
THEVertebræof theOs Sacrumgrow so close together inAdults, that they make but one large solidBONE, of aTriangular Figure; and yet not without theMarkof a four or five-foldDivision: As inChildren, it consists of many morePiecesorDivisions. However, itsBasisis tyed to the lastVertebræof theLoins, and theUpper partof itsSidesto theIlia; as itsPointis to theOs Coccygis.
THEOs Coccygisis also inAdults, for the most part, but one entireBONE; tho’ inyounger Personsit is compos’d of 3 or 4 smallDivisions; Of which theLoweris still less than theUpper; till theLastends in a smallCartilage. It is join’d in itsGlenoide Cavityto the Extremity of theOs Sacrum; being short and bentinwards: It supports theIntestinum Rectum, and yields to thePressureof theINFANTinTravail: ButMIDWIVESought not to thrust it back or repel it withViolence; No, they should rather handle itgently, if they would prevent dangerousConsequences, as well as greatPainto theWomaninLABOUR.
FROMhence it is manifest, thattheyare mistaken who imagine that theOpeningandEnlargementof thePELVIS, in making way for theINFANT, does depend upon theSeparationof theOssa Pubis: For it much more depends upon theyieldingof theOs Sacrum, or its giving way naturally; especiallyThis Partof it call’dOs Coccygis. Neither doth theStraitnessof theUpper Partof thePELVISso much occasion a difficultBIRTH, as thesmall Distancethat is betwixt thePointsof theOssa Pubis, call’dOssaSedentariaorSeat-Bones, and theOs Coccygis: No indeed, neither ofThesecan be any greatHindranceto the Passage of theInfant; since allBones, never so closely knit together withLigaments, may be movedextensivelyupon occasion, by carefully and gentlystretchingthe saidLigaments. But, in short, it most commonly happens, that theIll Positionof theInfantitself, or the badConditionandSituationof theWomb, orBoth, occasion a difficult or preternaturalBirth.
BUTI would here farther observe yet, that as theseBonesdiffer frequently both inFormandSize, according to the differentConstitutionof the Body; so neither aretheyalways of thesame Substance: For insome Women, we find a great manyNervousandCartilaginousLigaments, which penetrate into thesolid Substanceof theBonesthemselves; in which theLigamentsare so fast bound together, that it is hard to distinguish whether they areOneorMoreBones. From whence, however, it will hereafter appear, thatOne Womanis more easily delivered thanAnother; theBonesinOnebeing more firm and immoveable, altogether resisting anyRelaxation; which inAnotherare more loose and pliable, easily give way and yield freely to theForceof the Endeavouring and StrugglingINFANT.
THEContentsof thisSectionwill appear more evident, by looking curiously upon aFemaleSKELETON: In which (for Distinction’s-sake I reciteThis) that the lower Parts of theSeat-Bones, are generally moredistant, and not so much bentinwards, down towards the Point of theOs Coccygis, as in aMale SKELETON. Which Difference, in short, the OmniscientCreatorhas so order’d, for preventing difficultBIRTHS; and yet, notwithstanding all this wise Provision of Nature, they happen too often in the World. However, having thus, in fine, described thePelvisand itsBones, as far as is requisite forMIDWIVES, I come next, more particularly to describe that astonishingPieceofGod’sHandy-work, to which all the afore-mention’dPartsare ordain’d tominister,and that bothconjunctlyandseverally, without anyException: viz.