MECHANICAL EXTRACTION OF THE FCETUS. 



529 



The principal parts of the machine are: a kind of horse-collar (Fig. 

 184, A) with three stalks (B, C, D) intermediate between this collar 

 and a broad, fixed, female screw (E), which receives a movable screw 

 rod (H) that bears a revolving hook and chain (K) at one end; the 

 other end of the chain has also a hook to which the cord or cords fixed 

 on the foetus are attached. The collar is made of several pieces of light 

 wood superposed an^ bound together by an iron band applied to its pos- 

 terior surface. This band is perforated by three screwed holes placed in 

 a triangular position, and which receive the iron stalks. The anterior 

 face of the collar is so fashioned as to fit closely on the hind parts of the 

 animal, the space for the passage of the fcetus being about twenty inches 

 in diameter. The intermediate stalks (B, C, D) serve to transmit to the 

 collar the pressure exercised by the female screw ; they are about forty 



Fig. 1S4. 

 Bakon's Obstetric Machine. 



inches long, and each is composed of two pieces, one of these being 

 hollow (4, 5, 6), the other solid (i, 2, 3) : consequently, one fits into the 

 other, and the end opposite the collar enters one of the openings in the 

 flange of the female screw (E) ; a small thumb-screw (7, 8, 9) secures the 

 two portions of the stalk. The female screw is of iron or copper, the flange 

 being of wood, and its circumference provided with two handles to hold it 

 firmly when the machine is in use. The male screw (H) is of iron, and 

 screwed to the right ; one extremity articulates with the turning-hook(I) : 

 it is screwed in the contrary direction to the principal portion, so as not 

 to become unscrewed during the operation ; the other end has a four- 

 branched windlass which can be removed at will. 



To use the machine, the animal is made to lie ; the cords are attached 

 to the foetus in the usual manner ; the windlass handle is put on its place ; 

 the screwed stalk (H) is introduced into the female screw to about as far 

 as J ; the collar is applied to the animal's croup, and the three long stalks 

 are fixed — one end in the collar, the other in th.e flange. An assistant 



34 



