37 
EXPERIMENT NO. 14b. 
After the room in experiment No. H had been left closed 21+ hours. 
Quantity of formaldehyde found per cubic foot, 0.01028 gram. 
Yield of formaldehyde, 9.6 per cent. 
Weather: Gentle winds during intervening 24 hours. 
Temperature of room during experiment, 84° F. 
Relative humidity, 76 per cent. 
Absolute humidity, 9.38 grams per cubic foot. 
[+ means growth; — no growth.] 
Organism. 
B. pyocyaneus 
B. coli communis . 
B. dysenterix 
B. subtilis 
B. coli communis . 
B . subtilis 
, How exposed. 
Filter paper 
do 
do 
do 
Wilson method. 
do 
Time of exposure in minutes, 
and results. 
5 
10 
25 
30 
45 
60 
120 
+ 
+ 
+ 
+ 
- 
- 
- 
- 
- 
+ 
+ 
+ 
+ 
+ 
- 
— 
+ 
+ 
+ 
— 
- 
- 
- 
+ 
+ 
+ 
+ 
+ 
+ 
— 
EXPERIMENT NO. 15. 
Dilute formalin-permanganate method. 
Formalin, 600 c. c. 
Water, 600 c. c. 
Permanganate, 450 grams. 
Capacity of room, 2,000 cubic feet. 
Quantity of formaldehyde used per cubic foot, 0.107 grams. 
Quantity of formaldehyde found per cubic foot, 0.0279 gram. 
(Determination made by drawing air from the room, beginning 15 minutes after mixing the for- 
malin and permanganate, and consuming 1 hour 20 minutes in the drawing.) 
Yield of formaldehyde, 26.1 per cent. 
Weather: Light east wind, clear. 
Tempera- 
ture. 
Relative 
humidity. 
Absolute 
humidity 
(grams per 
cubic foot). 
Before mixing HCHO and KMnOj 
° F. 
79. 5 
Per cent. 
62 
6. 67 
After 10 minutes 
80.5 
87 
9. 66 
After 2 hours 
81.0 
81 
9. 13 
See Note, Experiment 9. 
[4- means growth; — no growth.] 
Organism. 
B . coli communis 
B. subtilis 
B. pyocyaneus .. . 
B. typhosus 
B . subtilis 
B. coli communis 
How exposed. 
Glass 
do 
Filter paper . . . 
do 
do 
Wilson method 
Time of exposure in min- 
utes, and results. 
