338 DIAGONSIS. 



latter. But as two elbows cannot, any more than two shoulders, 

 present at once at the strait, we may be sure that they are the knees, 

 from the mere fact that there are two such tumors together in the 

 strait at the same time; and as a single knee is generally accom- 

 panied with one foot, or ;at least with the breech, it will always be 

 easy to satisfy ourselves that we are touching some part of a lower 

 extremity, and not one of the. arms. There is, notwithstanding, one 

 circumstance that seems as if it might impose upon us; I mean the 

 simultaneous presence of a knee and an elbow. But besides the 

 rarity of these coincidences, we learn, by penetrating a little further 

 with the finger, that these parts, instead of approaching towards each 

 other at their origins, separate farther and farther from each other. 



809. Presentations of the breech have, more frequently than 

 others, led into error on this subject; where the buttocks have had 

 some difficulty in getting through the os uteri or the strait, they 

 swell like the vertex; the crease that separates them may be mis- 

 took for the sagittal suture; the coccyx and space in front or on 

 the side of it, for the occipital angle, the posterior fontinel, and 

 lambdoidal suture; and lastly, the ischia may be mistook for the 

 parietal protuberances; but this same crease, being a slit and not a 

 fold, the movableness of the coccyx, the presence of the anus and 

 of the genital parts, the roots of the members, &c., soon bring the 

 accoucheur back to the knowledge of the truth, when he has de- 

 parted from it for an instant. The anus and genital parts might be 

 mistook for a face presentation, were we not to remark that the 

 mouth, bordered with thick lips, contains a conoidal, movable, and 

 fleshy body, the tongue, and that the finger, when withdrawn from 

 the rectum, is found to be covered with meconium. Still, another 

 circumstance might deceive us. I shall give the particulars, because 

 the authors have omitted to mention them. Having been called 

 upon by Madame Lebrun, the midwife, to terminate a preternatural 

 labor, I thought I could feel the feet, the buttocks, the coccyx, and 

 anus; but my finger penetrated into an opening, bordered by thick 

 lips, at the bottom of which I felt a tubercle similar to the tongue. 

 Disconcerted by this combination of signs, I for a moment thought 

 I had to deal with a monstrous child; I again introduced my hand 

 further; I brought down the feet, and the emergence of the hips 

 soon put an end to my uncertainty. It was the vagina that I had 

 mistaken for the mouth, and the cervix uteri, which is very salient 

 at that age, had made me suppose I felt the tongue. In order to 

 obviate all hesitation in such a case, it is merely requisite to remem- 

 ber that the mouth is open behind, so as to be continuous with the 

 pharynx; whereas the vagina ends in a cul de sac, at the bottom of 



