_Extraction._ Where sufficient time has been allowed for the cranial bones to collapse, the finger inserted into the opening and acting as a blunt hook will, if assisted by the pains, be enabled to exert a sufficient degree of force to bring the head down to the pelvic outlet; by which time the action of the vagina and abdominal muscles in aid of the uterine efforts will soon succeed in pressing it through the os externum. By using the finger in this way we pull by that part of the head which is already lowest in the pelvis, and, therefore, run no risk of altering the position of the head and bringing it down in an unfavourable direction; this objection (among others) applies to the hook, whether it be fixed internally or externally, and thus frequently renders the passage of the head through the outlet and os externum more tedious, difficult, and painful, than it otherwise would have been. The craniotomy forceps are still more objectionable in all ordinary cases of perforation, for they not only alter the position of the head, but by tearing away portions of bone from time to time are very liable to wound the soft parts. From our own experience, we would recommend the application of the common curved forceps in all cases where the pelvic deformity is not of a very unusual degree, for by this means the hand is equally grasped and compressed, the soft parts to a considerable extent are protected by the blades, and the whole mass brought down exactly in the position in which it presented. On several occasions where the craniotomy forceps and crotchet have failed to move the head, the midwifery forceps has been applied, and the delivery easily and quickly accomplished. Dr. Smellie recommends the crotchet to be applied on the outside of the head, and was evidently aware that its position was liable to be altered by this means. He directs the practitioner to "introduce it along his right hand with the point towards the child's head, and fix it above the chin, in the mouth, back part of the neck, or above the ears, or in any place where it will take firm hold. Having fixed the instrument, let him withdraw his right hand, and with it take hold on the end or handle of the crotchet, then introduce his left to seize the bones at the opening of the skull (as above directed) _that the head may be kept steady_, and pull along with both hands." (vol. i. chap. 3. sect. 7. numb. 4.) Where there was considerable difficulty in bringing down the head, Dr. Smellie used to introduce a second crotchet opposite to the first, like the second blade of the forceps, and having locked them together was thus enabled to apply a greater degree of force.