350 
Journal of Agricultural Research 
Vol. XXXI, No. 4 
regular tubes gave positive tests at 7 to 8 inches from the top on the 
second day and at 8 to 9 inches on the remaining days. All of the 
upward penetration tubes gave positive tests at 7 to 8 inches from 
the bottom except two tubes which gave positive tests at 6 to 7 
inches on the fourth day. 
Penetration of Mercury in Soil Allowed to Stand Three Months 
If soil could be sterilized without being freshly cultivated it would 
often save expense and facilitate treatment. When only newly 
cultivated soil can be treated, every rain delays the work until the 
soil is again in condition to permit cultivation. It is much harder 
to haul loads of chemical solutions over newly cultivated soil. A 
single experiment was set up to give an indication of the penetration 
to be expected in soil permitted to stand without cultivation. As 
it seemed quite possible there would be a difference between soil 
receiving most of its moisture as rain and a soil receiving its moisture 
through subirrigation, the tubes were divided into two sets. 
Forty-eight tubes were filled with Manor loam and set in beakers; 
100 c. c. water was added to the tops of half of the tubes; 18 hours 
later 50 c. c. water was poured into the beaker under each tube; the 
remaining 24 tubes had 100 c. c. water added to the beaker for each 
tube and another 100 c. c. water added to the beaker three days later. 
Three months later these tubes were treated, half of each lot being 
treated 1 + 1 and the other half 1 + 0. Three tubes from each lot were 
tested on the second, third, fifth, and sixth days. As shown in Table 
XVI, the penetration of 1 + 0 was much better than 1 +1 in the tubes 
that had received 100 c. c. of water on top and 50 c. c. of water at 
the bottom, while in tubes receiving 100 c. c. twice at the bottom 
the 1 + 1 penetrated much better than the 1 + 0. No explanation of 
this variation has been suggested. Penetration in the poorer lot in 
each case was about equal to that obtained in freshly prepared air-dry 
soil. 
Table XYI. — Penetration of mercury in mercuric chloride and sodium chlorid 
solutions in tubes of Manor loam allowed to stand three months after having waler 
added to them 
Chemical 
treatment 
given 
Penetration on successive days after treatment 
Water added 3 months before 
treatment 
2 days 
3 days 
6 days 
6 days 
Inches 
Inches 
Inches 
Inches 
100 c. c. water applied to top and 
f “1+1 
6 7 to 8 (3) 
7 to 8 (3) 
7 to 8 (3) 
( 7 to 8 (2) 
\ 8 to 9 (1) 
8 to 9 (1) 
9 to 10 (2) 
60 c. c. to beaker at bottom of 
each tube_ 
l 1+0 
/ 6 to 7 (1) 
\ 7 to 8 (2) 
7 to 8 (1) 
8 to 9 (2) 
8 to 9 (1) 
9 to 10 (2) 
100 c. c. water applied to beaker 
+100 c. c. to beaker at bottom 
j i+i 
8 to 9 (3) 
/ 6 to 7 (2) 
\ 7 to 8 (1) 
/ 7 to 8 (1) 
\ 8 to 9 (2) 
8 to 9 (2) 
9 to 10 (1) 
/ 6 to 7 (2) 
\ 7 to 8 (1) 
8 to 9 (2) 
9 to 10 (1) 
nf p.anh t.nh« 
l i+o 
} 6 to 7 (3) 
} 7 to 8 (3) 
° For explanation of symbols see p. 332 and footnote of Table VII, p. 339. 100 c. c. of water is equal to 
1 H gallons per square foot of soil surface in the tubes used. 
b Numbers inclosed in parentheses show the number of tubes giving positive tests at the depths indicated. 
