86 
It is worthy of note here that although only half the quantities of 
formalin and permanganate were used in the preceding experiment 
as in the following one, the germicidal results in the former were better 
than in the latter. As the temperature was practically the same in 
the two experiments the difference in results is no doubt due to the 
higher humidity in the former experiment. This shows the impor- 
tance of humidity in disinfecting with formaldehyde gas, and, fur- 
ther, that regardless of the quantity of gas present the humidity 
should not be below a certain percentage. 
EXPERIMENT NO. 48. 
Formalin 3,000 c. c., permanganate 1,500 grams, equally distributed in six iron buckets, four of 
which were placed in the main sleeping compartment of car and one in the alleyway at each end. 
Weather: Clear and dry, light wind. 
Temperature in car at beginning of experiment, 77.5° F. 
Relative humidity in car at beginning of experiment, 58 per cent. 
Time of exposure, 2 hours (11.20 a. m. to 1.20 p. m.). 
Temperature in car after opening and airing 20 minutes, 83° F. 
Relative humidity in car after opening and airing 20 minutes, 48 per cent. 
[4- means growth; — no growth.] 
Organism. 
Place of exposure in car. 
Result. 
B. coli communis 
Toilet room 
Drawing-room 
4 - 
Floor main sleeping compartment 
Berth, upper No. 10 
4 - 
Berth, lower No. 6 
B. diphtherix 
Drawing-room 
Berth, upper No. 6 
Berth, lower No. 10 ' 
4 - 
B. typhosus 
Toilet room 
Drawing-room 
4 - 
Berth, upper No. 2 
Berth, lower No. 2 
Berth, lower No. 4 
4 - 
B. subtilis 
Toilet room 
4 - 
Drawing-room 
4 - 
Floor main sleeping compartment 
4 - 
Berth, upper No. 2 
4 - 
Berth, lower No. 4 
+ 
B. tuberculosis 
Floor main sleeping compartment 
4 - 
Sputum exposed by the Wilson method and injected into 
guinea pig; pig chloroformed 92d day; increased 415 grams in 
weight; spleen had only slight appearance of tuberculosis. 
Floor main sleeping compartment 
4 - 
Sputum exposed on carpet and injected into guinea pig; pig 
died of tuberculosis on 90th day. 
Control guinea pig died of tuberculosis 63d day. 
