178 MANUAL OF EQUINE MEDICINE. 



and two drachms of nitrate of potash in the form of a ball, 

 given twice daily for a week. 



But, presuming that after the administration of the 

 therapeutic agents the effusion rather tends to increase than 

 to become lessened in amount, we should not delay the 

 operation. We may use the ordinary trochar and canula, 

 or pneumatic aspirator, and should puncture the chest- wall 

 in the eighth or ninth intercostal space at a point midway 

 between the upper limit of the fluid and the bottom of 

 the pleural cavity. 



It is not necessary to remove all the fluid, as after the 

 escape of a fair quantity the rest may become absorbed by 

 the vessels, through which the circulation again passes 

 freely. 



If necessary, the operation may be repeated in a couple 

 of days. 



Tonics with nitric ether may be given after the opera- 

 tion, and the bowels should be regulated by laxative diet, 

 which should be of a nutritious character, and if necessary, 

 mild doses of oil, or other aperient, may be given in 

 addition. 



