MECHANICAL EXTRACTION OF THE FCETUS. 



521 



edy this imperfection, he has made forceps with the extremity of the blades 

 notched or hollowed out (Fig. 177), while the end of one of the branches 

 has a piece of metal with a slot in it attached by a hinge, and which is 

 intended to hold the blades together when the foetus is seized. 



Though this forceps has sometimes proved of service, yet 

 cases occur in which it is not so useful. 



When the Bitch is large, or of moderate size, forceps may 

 be employed with advantage, though they must be of various 

 dimensions. But when the animal is very small, as is usually 

 the case in difficult parturition in this species, the space oc- 

 cupied by the bows of the forceps — if they are ever so thin 

 — so increases the volume of the mass which has to pass 

 through the pelvic canal, that this instrument cannot be used. 



As we pointed out when studying the anatomy of this 

 region, the pelvis is cylindrical in carnivora, and if we sup- 

 pose its diameter to be three inches, and that of the head of 

 the foetus a trifle less, it will be seen that birth must neces- 

 sarily be difficult ; and this difficulty will be increased if the 

 vagina is narrow and rigid. When the forceps is used, the 

 difficulty is further exaggerated ; for when the blades are 

 passed on the head, the foetus is then augmented in size by 

 a quantity equal to their breadth multiplied by their thick- 

 ifess — the whole constituting a mass greater than the pelvic 

 cavity will permit tp pass through it ; so that delivery be- 

 comes impossible. Forceps, therefore, in small bitches, in- 

 creases the difficulties of parturition, and these difficulties 

 are all the more embarrassing as the animal is diminutive. 

 Recourse to this instrument is consequently contra-indicated, 

 and if delivery is to be effected, a means must be substituted 

 which presents less inconvenience. As a rule, the loss of 

 one or two puppies is not a matter of much moment, the 

 principal object being to save the mother by bringing the 

 act of parturition to a prompt termination. Tiie desideratum 

 is to apply an apparatus which will exert its force behind the 

 head of the foetus, as if the sum of the expulsive efforts was 

 directed from behind ; or as if a new force had been devel- 

 oped in the uterine cavity, which presses directly on the 

 summit of the head. 



After much consideration, Defays finally produced an ap- 

 paratus which fulfils these indications, and, besides its inge- 

 nuity, is very simple and easily applied. It consists merely 

 of two rather fine brass, or very pliable iron wires, which 

 can be easily twisted, and are yet strong enough to with- 

 stand a moderate amount of strain. The wires should be 

 at least sixteen inches in length, and looped in the middle, 

 so as to be applied to the foetus in t'lie following manner : 

 The first finger of the left hand being passed into the vagi- 

 na, serves to guide one of the loops towards the summit of 

 and behind the foetal head ; and it then conducts the loop of 

 the other wire beneath the head behind the jaw. This done, 

 the two wires on each side are twisted by a little machine 

 (Fig. 178) composed of a thin iron rod in a handle, the other end of 

 which is thickened and pierced by holes running nearly parallel to the 



Defays' Wire- 

 Extractor 



WITH THE Tor- 

 sion Rods. 



