ANT1IUAX 255 



become infected. The infection may occur by grazing on 

 infected pastures and by tile use of contaminated dry fod- 

 der, tlir spore enabling the organism to persist on the dry 

 material. 



Before the development of the procedure for protective 

 vaccination, the disease occurred yearly on many farms in 

 France. These were known as "anthrax farniv" The 

 continued persistence of the organism in the soil of a con- 

 taminated field is usually ascribed to the resistant powers 

 of the spores. It may be that growth may occur each sum- 

 mer in the soil, a new crop of spores being thus produced 

 to favor the continued existence of the organisms. Its 

 more frequent and constant appearance in stock pastured 

 on low, moist land is evidence of the growth of the organ- 

 ism under these conditions. The contamination of stables, 

 yards, or fields with anthrax bacilli is certain to make them 

 unsafe for a number of years. 



Symptoms. The rapidity of progress of the disease in 

 the individual has led to the division of the various cases 

 into three types: the peracute, the acute, and the subacute. 

 In the first the animal may show no visible symptoms until 

 a few hours before death. Indeed, so rapid is the progress 

 of the disease that the usual yield of milk may be obtained 

 at one milking and death occur before the next milking- 

 time. An artificially infected guinea-pig may show no vis- 

 ible symptoms two hours before death. The temperature 

 may reach 106 F. in the absence of all other symptoms. 

 With such a temperature the respiration will be increased 

 and the heart -beats so pronounced that they may be heard. 

 Later the animal becomes weak and stupid, and the temper- 

 ature falls to subnormal. 



In the acute type symptoms of nervousness are present, 

 manifested by kicking and convulsions. The visible mucous 

 membranes become bluish and the urine is often bloody. In 



