276 LOUIS PASTEUR. 



The pus of the first boil, which was situated on the 

 nape of the neck, was collected in great purity ; some 

 days afterwards, the pus of a second boil, then of a 

 third boil, was collected. The pus, or the blood- 

 stained lymph of the red swelling which preceded the 

 formation of the pus, were sown in a sterilised infusion, 

 and each time a microbe, formed of little spherical 

 points connected in pairs, frequently united in small 

 clusters, was seen to develop itself. The cultivating 

 liquid was sometimes infusion of fowl, sometimes of 

 yeast. In the infusion of yeast the little grains are 

 suspended in pairs throughout the liquid, which is 

 uniformly thickened with them. In the fowl infu- 

 sion, the grains are united into little clusters, which 

 cover the sides of the -vessels, the liquid remaining 

 clear as long as it is not shaken. 



New observations were made upon a series of 

 boils, in the case of a man sent to Pasteur by Dr. 

 Maurice Raynaud. The same parasite was again 

 found a unique parasite, distinct from all others. At 

 the Hospital Lariboisiere, a woman whose back was 

 covered with boils, offered another opportunity for ex- 

 periment, and with the same result. It appears cer- 

 tain, then, that every boil contains a microscopic 

 aerobic microbe, and that to it are due the local in- 

 flammation and the consequent formation of pus. 



"When guinea-pigs or rabbits are inoculated with the 

 cultivating liquids, little abscesses are formed, which, 



