1914) 
NOLTE—SALIVARY ORGANISMS AND AIR POLLUTION 51 
coccus from the air cocci was sought in the action of the two on 
various organic substances. Іп this capacity the several broths 
containing lactose, syringin, and coniferin, proved especially 
serviceable. In lactose broth the typical salivary coccus was 
positive, i. e., it produced acid, whereas the air cocci were 
negative. In the syringin and coniferin broths, the air cocci 
were positive, the typical salivary coccus negative. 
To determine whether or not particles of saliva were dis- 
seminated through the air during the acts of coughing, sneezing, 
and loud speaking, Gordon performed experiments in a large 
and in a small room, using, at first, Flügge's method of arti- 
ficially infecting the mouth with a living culture of Bacillus 
prodigiosus and placing sterile agar plates at various distances 
in front of and behind the speaker. After 3-1 hour of loud 
speaking, it was found that B. prodigiosus had been disseminated 
to a distance of 40 feet in front of and of 12 feet behind the 
speaker. In other experiments in which no artificial infection 
of the mouth was resorted to, but in which the characteristic 
salivary coccus served as the index of dissemination, it was 
found that after 1-1 hour of loud speaking Streptococcus brevis 
appeared on broth plates placed as many as 12 feet in front of 
and behind the speaker. In similar experiments in which 
speaking was continued for one hour in an ordinary conver- 
sational tone, no dissemination of the salivary Streptococcus 
could be detected. 
From his experiments Dr. Gordon inferred that there were 
certain streptococci normally present in saliva which are appli- 
cable for the detection of droplets of saliva in air in much the 
same manner that Bacillus coli can be applied for the detection 
of fecal matter in water. 
THE IDENTIFICATION OF THE Most CHARACTERISTIC SALIVARY 
ORGANISM 
With a view of determining the organism most characteristic 
of saliva, I have undertaken, as a first step, a bacteriological 
analysis of the saliva of a normal individual. In this examina- 
tion special attention was paid to the type of organism most 
abundantly present. Having determined the type, i.e., whether 
bacillus, coccus, or spirillum, characteristic reactions for it 
were next sought in order to render its recognition easy. Since 
