PASTURING AND SOILING II9 



satisfactory treatment for bad cases is tapping. This con- 

 sists in making a hole through the skin and muscles, over 

 the prominent swelling on the left side, into the rumen 

 or 'paunch/ thus allowing the gas to escape at once, reliev- 

 ing the animal. 



"The best method of tapping is by means of an instru- 

 ment called a trocar and canmda. A trocar is a sharp- 

 pointed instrument, five or six inches long, and about the 

 size of a lead pencil, with a handle at one end. Over the 

 point of the trocar slips a tube, called a cannula, not quite 

 as long as the trocar, with a wide flange around the upper 

 end of the tube, as shown in the illustration herewith. 



TROCAR AOT) CAKNUIiA, 



'To use a trocar and cannula, proceed as follows : Tie 

 the animal so it cannot get away. With a sharp knife, 

 make a small incision through the skin over the promi- 

 nent part of the swelling on the left side. This incision 



Trocar and Cannula 



should be made about half way between the point of the 

 hip and the last rib^ and should be large enough to admit 

 the trocar and cannula readily. The incision should be 

 made quickly; then the animal will not notice it. After 

 the incision is made the trocar and cannula are pushed 

 quickly in and directed downward, inward, and forward; 

 push the trocar in until the flange of the cannula rests 

 against the skin. Withdraw the trocar and the gas will 

 rush out; that is, it usually does so; occasionally, how- 



