COSTIVENESS. 397 



more frequent in sheep under two years old than at a later 

 period ; and is known by the staggering gait of the affected 

 animal, and its separation from the rest of the flock ; the 

 head is held unnaturally low or high, and is carried more 

 to one side than the other, inclining also the general move- 

 ments of the body to the same side. As the pressure of 

 the hydatid increases, the functions become still more 

 deranged : the sheep staggers about almost unconscious, 

 with dilated pupils, and loss of cud ; until coma or convul- 

 sions close the scene. Of the cure we would remark, that, 

 notwithstanding the hopes held out, it is not often obtained ; 

 for the situation of the hydatid is so diversified and so 

 obscure, that it is only when it directly points itself out by 

 its effects on the cerebral parietes, that we are able to detect 

 it with any degree of certainty. In such cases it may be 

 attempted to puncture the vesicle by means of any instru- 

 ment that will penetrate the bone with safety, after a slight 

 opening has been made through the integuments by a 

 scalpel. A rude instrument is a fine sharp gimlet, which 

 will effect a sufficient opening if passed as far as its screw, 

 or until the hydatid fluid flows, and will prove effective, by 

 evacuating the vesicle without danger of wounding the 

 brain. After the operation, in whatever way performed, 

 should the symptoms not mitigate, there will be reason to 

 suspect that a second or third hydatid remains, in which case 

 the trephine must be resorted to. Subsequent to its use, 

 stitch up the integuments, and secure the head from the 

 effects of cold, violence, or insects. Continental shepherds 

 attempt a rude cure by introducing a long pointed instru- 

 ment up the nose, through the frontal sinuses, and into 

 the cerebral cavity, by which means the hydatid is often 

 effectually destroyed, and ill consequences less frequently 

 result than would be supposed likely from such treatment. 



COSTIVENESS. 



Some horses are habitually costive, which arises either 

 from a defective secretion of the fluid of the bowels ; or, 

 that the absorbents act too strongly, and take up too much 

 of the liquid contents, by which the faecal mass becomes 

 dry, hard, and difficult to pass ; or it may, and frequently 

 does, arise from a defect in the formation of the bile, either 



