_Preparatory stage._--_Precursory symptoms._ For some time before the commencement of actual labour, a variety of changes are taking place which must be looked upon as the precursors of this process: during the last weeks of pregnancy, nature appears, as it were, to be preparing for the great change which is at hand, and to be making such arrangements as shall enable it to be completed with the least possible danger both for the mother and her child. One of the earliest warnings which we have of approaching labour is an alteration in the form of the abdominal tumour; the cervix uteri has by this time (especially in primiparæ) entirely disappeared; the presenting part of the child has therefore descended to the lowest part of the uterus; the fundus has sunk lower and more forwards; and from the diaphragm being enabled to act with greater freedom, the respiration is performed with more ease and comfort to the patient; she therefore feels more capable of moving about, and is in better health and spirits than for some time previously. Upon examination per vaginam, the head will be found deep in the cavity of the pelvis, covered by the lower and anterior segment of the uterus; the os uteri is still closed, and situated in the upper part of the hollow of the sacrum, forming merely a small circular depression. In women who have already had children, a portion of the cervix uteri is still remaining; it is thick and bulky; and in some cases, where the uterus has been greatly distended in several successive pregnancies, it is nearly as long as in the unimpregnated state; the os tincæ or os uteri externum is open, its edge irregular from former labours; the upper extremity of the canal of the cervix is contracted, and forms the os uteri internum; it has been closed during the greater part of pregnancy, but usually is now sufficiently open to admit the finger; the os uteri is neither so high up nor so far backwards in the pelvis as in primiparæ, and is reached with greater ease; whereas, the head of the child, instead of being felt in the cavity of the pelvis, generally remains at the brim until labour is more advanced.