76 BACTERIOLOGICAL DIAGNOSIS. 



tubercle bacilli in large numbers. The advantage of 

 getting the patient to wash out his mouth and using 

 only fasting sputum is obvious, for particles of food 

 may present exactly the same appearance. 



Having found such a mass pick it out by means of a 

 platinum loop or pair of forceps and transfer it to the 

 middle of a clean slide. Now place another slide on 

 the top of the first, squeeze them together and then 

 slide them apart. You should get two good uniform 

 films. Dry and fix. 



If there are no caseous masses pick out a mass of the 

 sputum at random and proceed as before. 



A better method is as follows : Half fill an ordinary 

 medicine bottle with carbolic lotion (i in 20) and add a 

 drachm or two of the sputum. Shake thoroughly for a 

 few minutes and place the bottle where you can give it 

 an occasional shake during the next few hours. Then 

 pour the milky emulsion which results into a conical 

 urine glass and allow it to stand for twelve hours or 

 more. Remove some of the deposit which will form 

 with a pipette and spread it into a thin film on a slide. 

 Dry and fix. 



Urine is treated in a similar way ; but here carbolic 

 acid (liquefied or in crystals) is added to the urine in 

 amount sufficient to convert it into a i in 20 solution. 

 This is allowed to deposit or (better) is centrifugalised. 

 Films are prepared from the deposit. 



Remember that they should be passed through alcohol 

 after staining. 



Pus is best carbolised in the same way as sputum ; if 

 very thin it may be treated like urine. The tubercle 

 bacilli will rarely be found in pus unless it is examined 

 soon after the abscess is opened, but may be detected 

 by inoculation experiments for long periods. 



