2 6 ME THODS OF EX A MINA TION. 



in all cases where the presence of micro-organisms is suspected, 

 whether in fluids or in fresh or alcohol hardened specimens. In the 

 case of fluids, where there is a quantity of albumen present, Baum- 

 garten's method is undoubtedly one of the most effective, and may be 

 applied to any of the fluids, though it is described in connection with 

 the detection and recognition of tubercle bacilli, to which further 

 reference will have to be made. 



Baumgarten's Method. 



22. Place a small portion of the fluid to be examined on a cover- 

 glass, which has been thoroughly cleaned with nitric acid, and then with 

 distilled water. With another cover-glass press the fluid out into as 

 thin a layer as possible, and wipe the margins with a scrap of blotting- 

 paper. " Separate the cover-glasses by sliding them from one another, 

 when each will be found to be covered on one side with a thin film 

 of sputum." x Allow the films so formed to dry, and then, holding 

 one of the covers with a pair of forceps, pass it, " about as quickly as 

 one cuts a slice of bread," three times through the flame of a spirit 

 lamp or a Bunsen's burner in order to coagulate the albumen, which, 

 as already stated, is present in these fluids. Then immerse the cover 

 slips in a solution of a couple of drops of ^ per cent, solution of 

 caustic potash, added to a watch-glass full of distilled water. Press 

 the cover-glass down on a slide, and examine under a high power 

 ( x 6oo), when the bacilli or micrococci may be observed as bright 

 refractile bodies, elongated or rounded, the elongated rods in some 

 cases showing strongly refractile bodies in their substance. It must 

 be remembered, in the case of micrococci, that minute granules of 

 coagulated albumen may be mistaken for these small round organisms, 

 whilst small crystals have been mistaken for bacteria, if this method 

 has not been fully and carefully carried out. 



Fresh or spirit-hardened specimens should be treated as follows : — ■ 

 After washing out the gum with warm carbolised distilled water,, or 

 getting rid of any embedding material (celloidin, paraffin, Sec.) which 

 may have been Used, place the sections in absolute alcohol, where 



1 See Lancet, 15th July 1SS2. 



