228 MICROBES, FERMENTS, AND MOULDS. 
virulent properties of the microbe. Hansen considers 
that alkalis, not acids, are the best antiseptics in this 
disease. 
Tubercular leprosy, termed elephantiasis by the 
ancients, is caused by tubercles seated in the skin, 
and containing a bacillus greatly resembling that of 
phthisis, but larger (Fig. 92). This microbe is anaé- 
Fig. 92.—Bacilli of teprosy, er a rene ae aaa connective tissue of the skin 
robic, and can only live in the dermic cells, in which 
it is encysted. Hence the treatment which experi- 
ence, preceding the theory, showed to be the most 
efficacious: instead of keeping the ulcers covered, they 
should be exposed to the air and sun, often washed, ° 
and kept as clean as possible. This disease, which is 
essentially contagious, is very rare in Europe, but 
common in Egypt and throughout Asia. 
