105 
EXPERIMENT NO. 67. 
Autoclave, formalin 2,000 c. c. 
Time required to vaporize formalin, 50 minutes. 
Autoclave changed from one end of car to other every 10 minutes during the process of vaporizing 
the formalin. 
Weather: Cloudy; moderate northeast wind. 
Temperature in car at beginning of experiment, 47° F. 
Relative humidity at beginning of experiment, 53 per cent. 
Time of exposure, 2 hours (12.25 p. m. to 2.25 p. m.) from time of beginning to introduce the gas 
Temperature in car after opening and airing 15 minutes, 40° F. 
Relative humidity after opening and airing 15 minutes, 52 per cent. 
[+ means growth; — , no growth.] 
Organism. 
Place of exposure in car. 
Result. 
B. coli communis 
Toilet room J 
-1- 
Drawing-room 
+ 
- — • - ~ — 
Floor main sleeping compartment 
+ 
-1- 
Berth, upper No. 12 
Berth, lower No. 8 
+ 
B . diphtherias 
Toilet room 
+ 
Drawing-room 
+ 
Floor main sleeping compartment 
4- 
'Berth, upper No. 11 
+ 
B. typhosus 
Toilet room 
+ 
Drawing-room >. 
+ 
Floor main sleeping compartment 
+ 
Berth, upper No. 7 
+ 
Berth, lower No. 3 
+ 
B . subtilis . . 
Drawing-room 
+ 
Floor main sleeping compartment 
+ 
Berth, upper No. 1 
-p 
Berth, lower No. 4 
The above results do not differ materially from those with the other 
methods described above. For comparison, experiments Nos. 46 and 
66 were done simultaneously, as were No. 61 and 65. Of the four 
guinea pigs used in this method two showed no lesions of tuberculosis, 
while the other two showed that the virulence of the organism had 
been diminished as compared with the controls. 
A longer exposure would no doubt have given better results, espe- 
cially in experiments Nos. 65 and 66. Evidently about the same tem- 
perature and humidity are required in this method to accomplish effi- 
cient disinfection as in the other methods. 
V. GENERATING LAMP. 
Two lamps were used in an experiment, placed one in either end of 
the main compartment of the sleeping car. Fifteen hundred c. c. of 
commercial wood alcohol were used in each lamp. ' 
The lamps were started, as previously described (p. 57), in the room 
experiments. As soon as they' began to give off formaldehyde gas, 
etc., the car was closed and the time of exposure of the organisms 
