340 
Journal of Agricultural Research 
Vol. XXXI, No. 4 
Table VIII .—Number of tubes giving 'positive tests for mercury with the hydrogen 
sulphide test , at the various depths on each day after application to Manor loam of 
1 gallon per square foot of mercuric chloride plus sodium chloride solutions y or 
of 1 gallon of solution plus water a 
In soil containing 4.3 per cent or less moisture 
Depth of penetra¬ 
tion 
1 day 
2 days 
3 days 
4 days 
5 days 
6 days 
7 days 
9 days 
Total 
number 
of tubes 
Inches: 
6 to 7__ 
Tubes 
3 
6 
Tubes 
2 
9 
1 
Tubes 
3 
23 
7 
Tubes 
Tubes 
1 
13 
9 
1 
Tubes 
Tubes 
Tubes 
9 
54 
26 
1 
7 to 8__ 
3 
6 
8 to 9_ 
3 
9 to 10_ 
In soil containing 10 to 16 per cent moisture 
6 to 7_ 3 
3 
6 
7to8 ._._l 3 
21 
15 
6 
3 
48 
8 to 9___ 
13 
19 
15 
8 
2 
6 
! 63 
9 to 10__1_ 
5 
15 
3 
4 
1 
I 28 
l 
i 
In soil containing 17 to 19 per cent moisture 
7 to 8_ 
6 
1 
3 
4 
2 
16 
8 to 9_ 
13 
9 
6 
13 
8 
11 
15 
75 
9 to 10_ 
5 
9 
11 
18 
7 
10 
15 
2 
77 
10 to 11 _ 
2 
1 
1 
1 
5 
' 1 
In soil containing 20 to 23 per cent moisture 
6 to 7 __ 
5 
fl 
5 
7 to 8_ 
4 
7 
5 
4 
20 
8 to 9 _ 
2 
2 
5 
6 
3 
18 
9 to 10_ 
1 
3 
1 
2 
1 
8 
i 
1 
Total.. 
459 
° This table includes the tubes from some sets used in special experiments which were not included in 
Table VI. The amounts of chemicals used per square foot in these special experiments varied from the 
equivalent of those required for one gallon of H Per cent HgCl2+2J^ per cent NaCl, the standard applica¬ 
tion. Since no increased penetration seemed to result from such increased amounts of chemicals it seemed 
permissible to include them here. 
The data are arranged to show the number of days elapsing from 
the time of application of the solution until the penetration tests 
were run. It will be noted that the maximum penetration was 
usually not obtained in less than three days. As previously stated 
penetration was determined by testing soil an inch at a time. A 
positive test in the soil sample from the 8 to 9 inch depth was con¬ 
sidered 8 inches in tabulating, even though the actual penetration 
may have been nearer 9 inches. Hence one may find an average 
penetration of 8 inches shown in the tables, whereas the penetration 
for the tubes included averaged more than 8 inches. In two tubes 
in which the penetration was 834 and 834 inches, positive tests would 
be secured in the 8 to 9 inch soil section and both tubes would be 
listed as showing 8 inches of penetration. A tube in which penetra¬ 
tion was barely 8 inches would give a positive test in the 7 to 8 inch 
soil section and hence would be listed as showing 7 inches of pene¬ 
tration. The average of these three tubes, 8 + 84-7, would appear 
as 8 — inches in the table instead of 834 inches. Although this may 
seem inexact it must be borne in mind that for absolute extermina- 
