I Doubt not in the least but _This_ and the _proceeding Chapter_ will seem needless, and appear superfluous to some Persons, in the _Practice_ of _MIDWIFERY_; namely, to such as know not the _New Improvements_ of this ART: But especially to such as are accustom’d to the _Use_ of INSTRUMENTS, they’ll appear altogether _Useless_ and _Vain_; since such _Practitioners_ can easily (upon any Occasion, without the curious _Anatomical Knowledge_ of _these Parts_) first slay the _INFANT_, and then either _deliver_ or _kill_ the _WOMAN_, as _Chance_ may _direct_ their _SHARPS_. BUT for my Part, because I have no Notion of such sort of WEAPONS, I shall endeavour to acquit my self more _honourably_, and teach my _Followers_ another way, and _That_ without BLOOD-SHED; as I hope will hereafter more amply appear. AND FIRST therefore in speaking of the _Bones_ of the _PELVIS_, I shall begin with the _OSSA Innominata_; which are _two_ large _Bones_ joined to the _Sides_ of the _OS SACRUM_. _They_ are compos’d of _Three_ distinct _Pieces_, each of which has its respective _Name_: The FIRST and _superior_ is call’d OS ILIUM; because the _Guts_ ILIA lie upon it directly. It is _Large_ and almost of a _Semicircular Figure_, a little _Convex_ and _Uneven_ on its _External Side_; as it is _Concave_ and _Smooth_ on the _Internal_. In short, it is join’d to the _Sides_ of the _three Superior_ VERTEBRÆ of the OS SACRUM, and is _Larger_ in _WOMEN_ than in _MEN_. THE SECOND and _Anterior_ is call’d OS PUBIS; which is united in the _Forepart_ to its _Fellow-BONE_ of the _other Side_, by an intervening _Cartilage_: By the Extension of which _Cartilage_, the OSSA PUBIS in _Young Women_, sometimes recede a little from _One another_, to facilitate a difficult BIRTH. THE THIRD is the _Inferiour_ and _Posteriour_, call’d OS ISCHIUM, or COXENDIX, which has a large _Cavity_ call’d _Acetabulum Coxendicis_; and This receives the _Head_ of the OS FEMORIS; the _Supercilium_ or _Top_ of which _Cavity_ joins the OS PUBIS. THESE _Three Bones_, until the Age of _Puberty_, may be seen distinctly, tho’ afterwards they grow together, and become _one BONE_, without leaving any Mark of _Division_. They adhere on each _side_ to the OS SACRUM by _two Strong Ligaments_; the _Upper_ of which passes from the _Posteriour Acute Process_ of the ISCHIUM to the SACRUM; as the _Lower_ joins the _Tuberculum_ ISCHII to the SACRUM.