THESE _Tubes_, to be brief, (in time of _COITION_) are erected by a copious Influx of _Blood_ and _Spirits_; which also, by the Assistance of their _muscular Fringes_, embrace the _OVARIUM_, transmit the _prolifick Masculine_ SEED, afterwards receive the _impregnated_ EGG, and at last convey it thence into the WOMB. In fine, these are all the _internal Parts_, as I conceive, tending to _GENERATION_. But more particularly, to proceed to [Illustration] CHAP. VII. _Of the PELVIS._ THIS being that _Cavity_ in which the WOMB is placed, and through which the _INFANT_ passes in time of _BIRTH_; it is my Opinion that a distinct _Knowledge_ of it is highly necessary for all _MIDWIVES_ to accomplish their _Practice_: For without that _Qualification_, they cannot help committing a great many _Blunders_, and being guilty of innumerable _Mistakes_; since they must proceed upon gross _Uncertainties_, and use their _Hands_ like _MEN_ groping in the _Dark_, as hereafter will more plainly appear. THIS is that _Cavity_ betwixt the OSSA INNOMINATA and OS SACRUM; which join themselves in the _Posterior Part_ of it on each side, by _Cartilages_ and _Ligaments_: so that they, forming there a strong and firm _Juncture_, compose this _Cavity_ of the _PELVIS_, which is vulgarly call’d the _Bason_ of the WOMB. THE upper Part of the OSSA PUBIS forms the _Borders_ of this CAVITY _before_, and the Hanging forwards or bending down of the OS SACRUM makes _Those_ of it _behind_; as the OSSA ILIA compose the _same_ on each side. THESE OSSA ILIA are (by _some_) call’d the _Wings_ and _Bounds_ of the _PELVIS_; but they are mightily mistaken, who imagine that they surround or encompass the _PELVIS_: For they are only annexed to it on _each side_, and more extended towards the _Back_ than the _Forepart_. As they are also very much in the _wrong_, who think that the _Cavity_ of the _PELVIS_ extends in its _Length_, according to the _Length_ of the BACK-BONE: since it rises from the _Bottom_ obliquely, ascending _Forwards_, and so proceeds, as if a Person might, through its _Passage_, easily touch the NAVEL. IN fine, it is here Remarkable also, that we do not always find the largest _PELVIS_ in _Women_ of the largest SIZE, but often the quite _contrary_; for it differs as the _INFANT_ does in _Bulk_, exactly answering to the _Bigness_ of its HEAD: And in some _Women_ it is _Deeper_, in some _Larger_, in some _Broader_, in some _Flatter_, in some more _Oval_, and in some at last _Rounder_. From whence arise sundry _Observations_ both useful and necessary, for the better _Information_ of _MIDWIVES_. [Illustration] CHAP. VIII. _Of the BONES of the PELVIS._