824 DISEASES OP SHEEP. 



the same hole, until past the split in the silver canula; 

 then withdraw the trocar, leaving the canula sticking in 

 the head, when the water will be forced from the hydatid, 

 showing that it has been pierced. Put the point of the 

 syringe into the canula, and draw out repeatedly, emptying 

 each time until no more water will come out, or the cyst, 

 has been drawn into the canula, which now withdraw, 

 taking care that the skin of the hydatid be caught hold of 

 by the forceps, which the operator should have ready in 

 his hand. Having removed the hydatid, leave the mouth 

 of the wound open, only placing a piece of clean rag as a 

 pledget over it, as water will escape for a day or two. 

 Put on the angular hood to keep the cloth and padding in 

 their place, and secure it by worsted ties. Care must be 

 taken, if the sheep has not been able to eat for some days, 

 that it get a bottle of gruel before operating, as the less 

 disturbance it is subjected to for some hours after the 

 operation the better, the brain taking a little time to adjust 

 itself to the cavity that has been made by the removal of 

 the hydatid. Neither must the sheep be put on too rich 

 pasture, as on recovering they are apt to take too much 

 food, which may cause inflammation in the head. Mark 

 well the side that has been operated on, as it very fre- 

 quently happens that there are more hydatids than one. 

 In a week or two, if the sheep be observed turning to the 

 opposite side, secure it a second time, and proceed as before. 

 There are occasionally more than one or two in the same 

 subject, and at the same time. Indeed, I have known as 

 many as five, and not one of them less in size than the yolk 

 of an egg. But tv/o are quite common, one on each side 

 of the brain, nearly under the seat of the horn. Occasion- 

 ally there is one behind the first lobe of the brain, which 

 is also easily taken out. 



