generally slip, it will bring more of the base of the wedge into the brim. The head must be small, or the pelvis large, to admit of success by this mode.

4. Shall we extricate the head by perforating? The wedge may be lessened, but even after this, delivery is not always easy unless part of the cranial vault be removed, so as to allow of the flattening in of the head.

5. Can we turn simply? It is the best course, but if the head is low it may be difficult to accomplish.

6. The chin will sometimes turn forwards at the very last moment, when the face is quite on the floor of the pelvis. If not, it may be possible to hitch the chin over the perinæum by drawing the chin forwards by forceps, and pulling the perinæum backwards. The chin thus outside, the forceps or lever may be applied to draw the occiput down under the pubes and backwards, so as to make the head revolve on its transverse axis, thus restoring flexion. You are in fact decomposing the base of the wedge. You deliver by a process the reverse of that of ordinary occipito-anterior labour. In this, the occiput escapes by a process of extension. In the mento-sacral position you deliver by promoting flexion. Or, to take our illustration from the mechanism of face-labour, you obtain flexion by causing the chin to turn over the coccyx or sacro-sciatic ligament as a centre, instead of over the symphysis. The latter is the natural mode, but it may be that the first alone is possible. This is a case in which incision, bilateral, of the perinæum, here acting as an obstructing posterior valve, may be performed in order to facilitate the release of the chin.

LECTURE V.

THE FORCEPS IN DISPROPORTION OF THE PELVIS-DEGREES OF DISPROPORTION-INDICATIONS IN PRACTICE-THE MECHANISM OF LABOUR IN CONTRACTION FROM PROJECTING PROMONTORY-THE CURVE OF THE FALSE PROMONTORY-DEBATABLE TERRITORY ON THE CONFINES OF THE SEVERAL OPERATIONS-PENDULOUS ABDOMEN-THE CAUSE OF DIFFICULTY IN PENDULOUS ABDOMEN-SUSPENDED LABOUR-THE MODE OF MANAGEMENT-DYSTOCIA FROM FAULTY CONDITION OF THE SOFT PARTS-CONTRACTION OF THE CERVIX UTERI RIGIDITY SPASM-DEVIATION- -HYPERTROPHY·

CICATRIX

CLOSURE-CEDEMA-THROMBUS― CANCER -FIBROID TUMOURS-THE NATURAL FORCES THAT DILATE THE CERVIX THE ARTIFICIAL DILATING AGENTS-VAGINAL IRRIGATION - WATER-PRESSUREINCISIONS-RESISTANCE OFFERED BY THE VAGINA, VULVA, AND PERINÆUM.

Now we have to consider what the forceps can do in cases of disproportion; for instance, where the brim is too small to allow the head to pass by the unaided powers of the uterus. This brings up the problem of the compressibility of the head under the forceps, and

the comparison of the advantages of the forceps with those of turning. The degrees of contraction of the brim may be classified approximatively in the following manner :

Scheme of Relation of Operations to Pelvic Contractions, Labour at Term. Conjugate diameter reduced to

The first degree
The second degree. 3 to 3 in.,

The third degree
The fourth degree

4 to 34 in., admits the forceps, opposed to the bi-
parietal diameter of 3 to 4 in.
of turning, opposed to the bi-
mastoid diameter of 3 in.
of craniotomy and cephalotripsy.
of Cæsarian section.

3 to 1 in.,
below 11⁄2 in.,

If you have the advantage of bringing on labour at seven months, then you may eliminate the Cæsarian section, and slide down the scale of operations, so that craniotomy shall correspond with the fourth degree, turning with the third, and the forceps with the second, whilst the first degree, being reduced to the conditions of natural labour, may require no operation at all.

Scheme of Relation of Operations to Degrees of Pelvic Contraction under

The range of application of the forceps is, I believe, not great. The head cannot be compressed by it quickly. The proper use of it is to aid that natural process of moulding which always takes place in protracted labour. Now, this is a gradual, even a slow process. The head is seized by the long forceps in

the way already described. The handles are firmly grasped with both hands, and especial care is required to extract well backwards in the axis of the brim, so as to make the head revolve round and under the projecting, overhanging promontory as a centre. Here I may pause to show that, in labour with conjugate contraction from rickets, the promontory possesses a like importance at the brim or entry of the pelvis to that

s, the symphysis pubis, the centre of Carus' curve c D; A E, the axis of the brim, forming an acute angle, not less than 30°, with the datum-line A B. The uterus and the child's body nearly corresponding with the axis of the pelvic brim, the head enters its natural orbit, represented by Carus' curve, at once.

which the symphysis pubis possesses at the outlet. The promontory is a turning-point-a centre of revolution of the head, just like the symphysis. The curve round the pubes, which Carus described, has its counterpart in a curve round the promontory. In

ordinary labour, with a well-constructed pelvis, the head enters the pelvis, and reaches nearly to the floor, without deviating much from the straight line which represents the axis of the brim. orbit, the circle of Carus, at once.

FIG. 30.

Thus it enters its

PELVIS CONTRACTED BY RICKETS TO SHOW THE CURVE OF THE FALSE PROMONTORY.

s, the symphysis, the centre of Carus' curve CD; FP, the false promontory, the centre of the false curve E G; G, the point of intersection of the two curves where the head passes from the false to the true orbit; A H, the axis of the brim, forming a very acute angle, varying from 30° to 20° or less, with the datum-line A B. The head is thrown over the pubic symphysis by the projecting promontory. The forceps draws backwards in line a H to bring the head under the promontory in the orbit of the false promontory.

But a projecting promontory, involving, as it commonly does, a scooped-out sacrum below, disturbs this course. The promontory must be doubled. The head must move round this before it can strike into its natural orbit. I propose to call this curve the curve of the false promontory.