for Twenty Years in succession on the same Land. 107 
averafrc productiveness wltli moderate manuring, but was unfa- 
vourable for high manuring, that is for the growth and maturing 
of large crops. The selected plots in the experimental barley 
field gave the following results : — 
'J'able V. — Quantity and Quality of Barley on Selected Plots. Fourth Season, 1855. 
[ riois. 
7 
1 O 
4 O 
1 A 
4 A 
4 A A 
4C 
MANURES, PER ACRE. 
14 Tons Farm-yard Manure 
Unmanured 
Mixed Mineral Manure 
200 lbs. Ammonia-salts 
Mixed Mineral Manure, and"! 
200 lbs. Ammonia-salts . . / 
Mixed Mineral Manure, andl 
400 lbs. Ammonia-salts .. / 
Mixed Mineral Manure, and 
2000 lbs. Eape-cake 
PRODUCE PER ACRE, &c. 
Dressed 
Quantity. 
Corn. 
Weipht 
per 
Bushel. 
ToUl 
Corn. 
Straw 
and 
Chaff. 
Total 
Produce 
(Corn and 
Straw). 
Bu^liels. 
lbs. 
lbs. 
Cwfs. 
lbs. 
50J 
52-9 
2765 
27i 
58.'>2 
31 
52-4 
1773 
I'i 
3745 
3"b 
53-1 
20G7 
18 
4082 
44^ 
51-8 
2443 
5148 
48i 
52 '0 
2G.59 
31 
G134 
495 
48-9 
2582 
39| 
7054 
513 
49-5 
2783 
0993 
Com 
to 
100 
Straw. 
89-6 
89- 9 
102*6 
90- 3 
7G-5 
57-7 
GG-l 
A wet and warm July, and the beginning of August also wet, 
following upon a cold and dry spring and early summer, and, 
therefore, acting upon a backward crop, ensured a considerable 
bulk of produce ; and with comparatively favourable conditions 
immediately before harvest, the quantity of corn per acre, as 
well as that of straw, was also above the average of the 20 years ; 
excepting in some of the cases of the heavier crops, which were 
much laid. The corn-yielding characters of the crop varied, 
however, very considerably ; the proportion of corn to straw, and 
the weight per bushel of the dressed corn, being generally consi- 
derably the lower, the greater the proportion of nitrogen to 
mineral constituents in the manure ; that is to say, the more the 
manures supplied the conditions favourable to luxuriance and 
bulk, rather than to seeding tendency. Thus, by mineral manures 
alone, there are only 37-^ bushels of corn, and 18 cwts. of 
straw, but 102 parts of corn for 100 of straw, and more than' 53 
lbs. weight per bushel ; whilst with the same mineral manure 
and 400 lbs. ammonia-salts per acre, there are nearly 50 bushels 
of corn, and nearly 40 cwts. of straw, but less than 58 parts of 
corn to 100 of straw, and less than 49 lbs. per bushel. The very 
varied conditions of manuring supplied in the experimental field 
have, therefore, furnished, in their results, a striking illustration 
of how differently the same conditions of season may affect the 
produce of light and of heavy, or of deficiently or highly manured 
land ; and how an excess of rain during the actively growing 
