THE PLEURA. 121 



origin is suspected) a considerable quantity of the fluid 

 an ounce or more should be enclosed in a bottle which 

 has been sterilised by boiling, and forwarded at once. 



Where the diagnosis is to be made by cultural 

 methods, and the cultures are not to be made on the 

 spot, the fluid is best stored or sent to a laboratory in 

 pipettes. These are to be filled from the syringe direct ; 

 the needle is to be removed and the end of the pipette 

 (sterilised by being passed through the flame) is passed 

 into the fluid and filled by gentle suction at the other 

 end. Each end is then sealed in a flame, care being 

 taken not to heat the fluid. Two or three such tubes 

 should be sent. 



Clear fluid from the chest rarely, if ever, shows any 

 micro-organisrns on microscopical examination. Cul- 

 tures are usually sterile ; where streptococci or pneu- 

 mococci are found the inflammation is likely to pass on 

 into suppuration. The great majority of these cases of 

 " simple" acute pleurisy are really due to the tubercle 

 bacillus, but their true nature can only be demonstrated 

 by inoculation experiments. 



Where any question arises as to the nature of a case 

 of simple pleurisy the practitioner is recommended not 

 to attempt the examination himself, but to send samples 

 of the fluid in pipettes to a laboratory ; if animal experi- 

 ments are necessary a larger quantity of fluid should be 

 sent in a sterilised bottle. 



Purulent pleurisies (empyemata) may be caused by 

 many organisms, the most common being the pnemo- 

 coccus, streptococci, staphylococci, and the tubercle 

 bacillus. 



The pneumococcus is readily demonstrated by a 

 microscopical examination, the method to be employed 

 being the same as that previously described. 



