12 BULLETIN 1149, U. S. DEPARTMENT OF AGRICULTURE. 
Table 5. — Hydrocyanic acid (parts per million) in fumigated field corn. 
Sodium 
cyanide. 
Number 
of times 
chamber 
was evac- 
uated. 
Hydrocyanic acid after — 
day. 
1 day. 
4 days. 
7 days. 
14 days. 
30 days. 
60 days. 
90 days. 
Oz. per 
100 cu. ft. 
1.'.'.'."'. 
1 
1 
2 
2 
2 
2 
4 
4 
4 
4 
6 
•6 
6 
6 

1 
2 
3 

1 
2 
3 

1 
2 
3 

1 
2 
3 
7.5 
4.2 
1.2 
2.5 
2.1 
1.2 
.8 
1.7 
3.3 
2.5 
2.5 
3.3 
3.3 
4.2 
3.3 
4.2 
6.6 
5.0 
6.6 
1.2 
None. 
.8 None. 
. 8 None. 
. 8 ! None. 
62 
25 
12 
8 
42 
25 
25 
17 
33 
33 
33 
33 
5.8 
8.3 
5.0 
5.0 
6.6 
10 
8.3 
6.6 
5.0 
10 
6.6 
12 
1.7 
1.7 
1.7 
1.7 
3.3 
3.3 
3.3 
2.5 
3.3 
5.8 
5.0 
6.6 
1.2 
1.2 
1.7 
1.7 
2.5 
2.9 
2.1 
2.5 
3.3 
5.8 
5.0 
5.8 
1.2 
1.2 
1.7 
1.2 
1.7 
2.9 
1.7 
2.1 
2.1 
5.8 
3.3 
h 
0.8 
1.2 
1.2 
1.2 
1.2 
2.1 
1.7 
2.1 
2.1 
5.0 
3.3 
3.7 
0.8 
.4 
.8 
.4 
1.2 
1.7 
1.7 
1.7 
1.7 
4.2 
3.3 
3.3 
Table 6. — Hydrocyanic acid (parts per million) in fumigated cowpeas. 
Number 
Hydrocyani 
3 acid aftei 
Sodium 
cyanide. 
of times 
chamber 
was evac- 
uated. 
| 
day. 
1 day. 
4 days. 
7 days. 
14 days. 
30 days. 
60 days. 
90 days, j 
Oz. per 
WOcu.ft. 
1 
1 
1 
1 
2 

1 
2 
3 

6.2 
16 
4.2 
4.2 
5.0 
4.2 
4.2 
3.3 
3.3 
4.2 
4.2 
4.2 
2.5 
2.5 
2.5 
2.5 
1.7 
2.1 
1.7 
2.1 
1.7 
1.2 
1.7 
1.2 
1.7 
.8 
• 8 
1.7 
1.2 
1.7 
.8 
1.2 
1.7 
56 
16 
2 
1 
33 
16 
5.0 
3.3. 
2.5 
2.1 
2.1 
1.7 
2 
2 
21 
17 
5.0 
4.2 
2.5 
2.1 
1.7 
1.7 
2 
3 
16 
11 
4.2 
3.3 
3.3 
2.1 
2.1 
1.7 
4 

83 
33 
17 
6.6 
5.8 
5.8 
3.3 
2.1 
4 
1 
50 
33 
13 
5.0 
5.0 
5.0 
4.2 
3.3 
4 
2 
42 
33 
8.3 
5.0 
4.2 
4.2 
4.2 
3.3 
4 
3 
42 
23 
6.6 
5.8 
5.8 
5.0 
3.3 
3.3 
6 

33 
17 
8.3 
8.3 
6.6 
4.2 
4.2 
3.3 
6 
1 
83 
27 
8.3 
8.3 
7.5 
t-o 
6.6 
5.0 
6 
2 
130 
27 
17 
13 
5.0 
5.0 
5.0 
4.2 
6 
3 
100 
40 
13 
12 
10 
6.6 
6.6 
5.0 
No hydrocyanic acid was found in unfumigated samples of any of 
the products, showing that none of it was naturally present in them. 
All of the seeds absorbed hydrocyanic acid on fumigation. The 
results obtained on the day of fumigation have little comparative 
significance, since much of the gas was loosely held and variations of 
three or four hours in the times of standing were unavoidable. They 
show, however, that the quantity then present is fairly large. Most 
of it disappears during the first few days. In fact, in most cases the 
hydrocyanic acid content, on the fourth day, was not more than 5 
parts per million. After this time there was an extremely slow dis- 
