526 OBSTETRIC OPERATIONS. 



From some measurements made by Saint-Cyr, the pelvis of the Mare 

 and Cow, and which is nearly cylindrical, maybe reckoned at 1600 square 

 centimetres (248 inches) of internal surface ; and it is on this expanse 

 that is distributed, in a nearly uniform manner, the eccentric pressure 

 which the chest of the foetus transmits to the walls of the genital canal, 

 to which it is very closely applied during its passage outwards. If, then, it 

 be admitted that the total of this eccentric pressure measures about one- 

 half the tractile force expended on the foetus, it will be easy to find, by a 

 simple calculation, the pressure on each square inch. Supposing the 

 traction to be equal to 1540 pounds — the estimated strength of seven or 

 eight men pulling with all their force at the cords — the pressure on each 

 square inch would be about 73^ ounces ; or one half that exerted on the 

 same extent of surface with a tractile force of 132 pounds, in woman ! 



Saint-Cyr does not pretend that these calculations give a rigorously 

 exact measure of what really takes place during parturition ; but he be- 

 lieves th^ may assist, up to a certain point, in explaining certain facts in 

 comparative obstetrics which otherwise would remain obscure : how, for 

 instance, natural birth, which is always so painful in woman, is compar- 

 atively painless in the larger animals ; and why traction, the very idea of 

 which frightens the accoucheur of woman, is, in the majority of instances, 

 so well sustained by the veterinary surgeon's patients. 



It must be confessed, however, that we have as yet no certain data by 

 which we can estimate the exact amount of force necessary, or which 

 may be employed without danger ; and on this point the opinions of the 

 best authorities are widely divergent. Some declare for moderate trac- 

 tion — two, three, or four men at the most, pulling simultaneously at the 

 cords with all their force, are, in their opinion, quite sufficient in all 

 cases, if well managed ; and they assert that it is rash and dangerous 

 to employ more. Others do not hesitate to have recourse to more ener- 

 getic traction,, and are not afraid of employing the combined strength of 

 six, eight, or ten strong men ; being convinced that the parent suffers 

 more from protracted labor than powerful traction : and not unfrequently 

 their success justifies their boldness. 



Donnarieix admits that three assistants are usually sufficient with the 

 Cow : one at the head, another at the tail, and the third to aid the opera- 

 tor ; while ten are needed for the Mare : one at the head, another hold- 

 ing the rope which confines the limbs of the animal, and prevents its do- 

 ing damage, a third to hold the tail, a fourth to assist the operator, and 

 the other five or six to pull at the foetus when necessary. Zundel, how- 

 ever, is of opiniori that these numbers are somewhat exaggerated ; very 

 often more than three assistants are required for the Cow, and if more 

 than six are needed for the Mare, it is better to have recourse to mechan- 

 ical means ; as too many assistants hamper the operator, and are often 

 in each other's way, while their united strength cannot be usefully ap- 

 plied. 



The assistants should be strong, and have had some experience in 

 handling animals ; some of them are to maintain the creature in a favor- 

 able position, while the others aid the attempts at extraction, under the 

 orders of the operator. The tractile efforts should be made simultane- 

 ously, without jerking, but in a continued and energetic manner, and 

 always in the direction of the axis of the pelvis — in a straight line behind 

 the animal. The direction of the traction may, however, be a little down- 

 ward in the anterior presentation, lumbo-sacral position, until the withers 



