PLAGUE OX VAEIOUS FOOD STUFFS. 
[By Passed Assistant Surgeon II. D. Geddings, Marine- Hospital Service.] 
fJANUAKY II, 1901. 
The experiments were continued from the point where Dr. Eosenau's 
preliminary note left otf, and have been the subject of continuous obser- 
vations in this laboratorv for more than a vear from that time, havino- 
only been brouo-ht to a conclusion within the past sixty days. 
In o-eneral terms it mav be said that the further observations have 
^ %> 
simply confirmed his preliminaiy views. The growth of the bacillus 
continued, reaching under various conditions of temperature and mois 
ture to a period of one hundred and twent}"-tive days on bone dust, 
where moisture was preserved, and at a temperature of 37^ C. ; ninety- 
seven days on crash, temperature 22° to 29° C. ; ninety-six days in 
distilled water, temperature 17° to 19° C. ; ninet\^-seven days in tap 
water, and other periods too numerous here to mention. 
But 1 would beg here to remind you that while these results are 
entirely beyOnd question, and while no effort was spared to make the 
conditions simulate those naturall}" obtaining, there were in the end 
some decided departures from the normal which would obtain under 
conditions of commerce, trade, etc. 
The experiments all showed, too, that under conditions of dryness, 
exposure to sunlight, and to temperatures above the normal, but not 
very elevated, the life of the l)acillus was short. 
Again, too, I would invite your attention to the fact that a condition 
which obtained in all these experiments was one very far from obtain- 
ing under normal conditions, viz, the fact of an intentional, abundant 
inoculation with a pure culture of the materials subiected to test, and 
this cidture one of known activity and virulence. 
A second depaidure from normal conditions was in the fact that all 
the materials receiving the abundant inoculation of the virulent pure 
culture were sterile. In other words, the plague bacillus was not 
only put to growing under the before-mentioned favorable conditions 
of heat and moisture, but was relieved in toto from that microbial 
symbiosis which, in the economy of nature, plays .so important a ])art 
in the suppression of pathogenic organisms. 
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