434 Agricultural Chemistry. 
the results obtained in the field in question, during a period of 
eleven years of the successive growth of wheat. 
Table I. 
Knmmanj.~'Re?,VL\t% of Experiments on the Growth of Wheat. 
Average Total Produce, and Total Increase (Corn and Straw), lbs. per Acre. 
Series. j 
General Description of Manures. 
Number 
of 
Years. 
Number 
of 
Cases. 
Total 
Produce 
(Corn 
and 
Straw). 
Total 
Increase 
(Corn 
and 
Straw). 
1 
2 
3 
n 
8 
11 
27 
40 
11 
lbs. 
2864 
3018 
5036 
lbs. 
2172 
4 
5 
6 
Ammonia-salts, only (Standard Amount) .... 
Nitrate of Soda ( = do. do. ) .... 
Ammonia-salts ( = do. do. ) with Minerals 
Ammonia-salts ) / j j \ j j 
and Rape Cake ] ^ = '^^^ ) ^o- 
9 
3 
9 
6 
36 
4 
117 
12 
4857 
490" 
5531 
5540 
1993 
2043 
2667 
2676 
8 
9 
10{ 
Ammonia-salts (less than Standard) do. 
Ammonia-salts (more do. do. ) do. 
Ammonia-salts 1 r ^ i i \ i 
and Rape Cake f C*^"' > "^O" 
do. 
do. 
do. 
6 
8 
5 
17 
31 
22 
4536 
6445 
6016 
1671 
3581 
3152 
The plan of this Table (I.) is as follows. We have taken the 
average total produce per acre (corn and straw) of all the plots in 
each separate year which were unmanured, and then the average 
of these for the eleven years of the experiment : the number of 
cases in all, as seen by the Table, amounting to 27. In like 
manner the average is taken of all the cases in each year in which 
mineral manures alone were employed, and then the average of 
these results of the individual years, by dividing their sum by the 
number of years ; and so on, with the cases where farm-yard 
manure, ammoniacal salts, or any of the other characteristic con- 
stituents or combinations, as indicated in the Table, were em- 
ployed. The last column in the Table — that of total increase — • 
represents the average annual total increase in lbs. (that is, corn 
and straw together), obtained from the manured over that of the 
unmanured plots. 
We are not, it is true, favoured with any numerical statement 
whatever, either summary or in detail, of the experiments on the 
" Liebig's Height" ; but we should not ourselves have thought 
of asking confidence in such a mere condensed summary as we 
now give, were it not that many of the results which go to form 
it, are already before the readers of this Journal, and the remainder 
we trust will be so in the course of time. This being so, we do 
not doubt that this summary will be accepted as both much more 
convenient, and better adapted for the discussion of the more 
prominent and characteristic facts, than a series of elaborate 
