DIAGNOSIS BY METHOD OF STEAUSS. 397 



over them drop by drop. For small sections three or 

 four drops are sufficient. Under no circumstances 

 should the alcohol be allowed to act for more than 

 one-quarter of a minute. Clear in xylol and mount 

 in xylol balsam. 



By method b the tissues are better preserved than by 

 method a, by which they are dried. 



Very good preparations are also obtained by the use 

 of Loffler's alkaline methylene-blue, if care be taken 

 not to stain for too long a time nor to decolorize too 

 energetically with alcohol. 



No method of contrast-stain for this organism in 

 tissues has been devised. 



In properly stained tissues the bacteria will be found 

 most numerous in the centre of the nodules, becoming 

 fewer as we approach the periphery. They usually lie 

 between the cells, but at times may be seen almost 

 filling some of the epithelial cells, of which the nodule 

 contains more or less. They are always present in 

 these nodules in the tissues ; they are rarely present 

 in the blood, and, if so, in only small numbers. 



DIAGNOSIS OF THE DISEASE BY THE METHOD OF 

 STRAUSS. From what has been said, the diagnosis of 

 glanders by routine bacteriological methods is certain 

 and relatively easy, but requires time. In clinical work 

 it is of great importance for the diagnosis to be estab- 

 lished as quickly as possible. With this in view Strauss 

 devised a method that has given entirely satisfactory 

 results. It consists in introducing into the peritoneal 

 cavity of a male guinea-pig a bit of the suspected tissue 

 or culture. If it be from a genuine case of glanders, 

 the testicles begin to swell in about thirty hours, ^nd 

 as this proceeds the skin over them becomes red and 



