38 LOCALIZATION OF MICRO-ORGANISMS. 



torns, become arrested, and find at the same time the necessary 

 nutrient medium for their multiplication. These questions have 

 been made the subject of patient experimental inquiry by a number 

 of investigators, the most important results of which will now be 

 mentioned. 



1. BACILLI OF ANTHRAX. Huber (" Experimented Unter- 

 suchungen liber Localisation von Krankheitsstoffen," Virchow's 

 Archiv, B. vi., 1886) calls attention to the circumstance that a 

 number of infectious diseases, such as tubercular affections of the 

 bones and joints, certain cases of pya3mia, osteomyelitis, and diffuse 

 suppurative inflammation in different tissues, are liable to follow 

 injuries unattended by infection from without. Again, we have 

 local infective processes which occur as complications during the 

 course of typhus and typhoid fevers, syphilis, and other infective 

 diseases. Through these extraneous influences, or accidental con- 

 ditions, certain parts of the body are rendered more susceptible to 

 the development of serious local disturbances under the action of 

 infective germs than the remainder of the body ; in other words, a 

 local predisposition, a locus minoris resistentice, is created. The 

 experiments of the author were made on rabbits, in which, by the 

 application of croton oil to the ear, he produced a tissue lesion by 

 the inflammation which followed. Only one ear was thus treated, 

 the other being left in a normal condition in order to compare the 

 results of the subsequent action of pathogenic microbes upon nor- 

 mal and inflamed tissues. The virus selected was a pure culture 

 of the bacilli of anthrax, and the reliability of the culture was 

 always tested before inoculations were made. The inoculation was 

 always made at the root of the tail, as far as possible from the seat 

 of inflammation produced by the croton oil. According to the 

 stage of inflammation in which the action of the bacilli of anthrax 

 was intended to be studied, the croton oil was applied either before 

 or after the inoculation. Immediately after death the ears were 

 removed and carefully preserved for subsequent examination, at 

 the same time serum and blood were separately taken in sterilized 

 glass-tubes from the inflamed ear under strict antiseptic precau- 

 tions. For microscopical examination the specimens were carefully 

 stained, while cultivations were made by inoculating sterilized 

 nutrient fluids, as at that time the method of cultivation on solid 

 nutrient media inaugurated by Koch was not known. These ex- 

 periments enabled the author to state that in all stages of the 

 inflammatory process the bacilli were never found outside the walls 

 of the capillary bloodvessels in the tissue placed in a condition of 

 inflammation by the croton oil. Their number within the blood- 

 vessels depended upon the conditions of the inflamed bloodvessels. 

 During the first stage of inflammation, marked by oedema without 



