184 BACTERIOLOOr. 



and those from -which these bodies are absent ? When 

 cultivated in sugar-bouillon in the fermentation tube, 

 what proportion of gas is evolved under known con- 

 ditions ? How much of this gas is carbonic acid and 

 how much is explosive? 



12. At what temperature does it thrive best, and the 

 lowest and highest temperatures at which it will de- 

 velop? What is its thermal death-point, both by 

 steam and dry-air methods of determining this point? 



13. What is its behavior when exposed to chemical 

 disinfectants and antiseptics ? does it withstand drying 

 and other injurious influences, both in the vegetative 

 and spore stages ? The germicidal value of the blood- 

 serum of different animals may also be tried upon it. 



14. Its pathogenic powers — modes of inoculation by 

 which these are demonstrated ; quantity of material 

 used in inoculation ; duration of the disease and its 

 symptoms; lesions produced, and distribution of the 

 bacteria in the inoculated animal ; which animals are 

 susceptible and which immune, and the character of 

 its pathogenic activities ? Variations in virulence, and 

 the probable cause to which they are due. Can they 

 be produced artificially and at will ? 



15. The detection of specific, toxic, and immunizing 

 products of growth. 



