272 HOW CROPS FEED. 
of ashes of clover, and bicarbonate of potash, in order that 
the plants growing in it might have an abundant supply 
of all the ash-ingredients they needed. Finally, the soil 
of pot D received the same mineral matters as pot C, and, 
in addition, a small quantity (1.4 gram) of nitrate of pot- 
ash. The seeds were sown on the 5th of July, and on the 
30th of September, the plants had the relative size and 
appearance seen in the figure, where they are represented 
in one-eighth of the natural dimensions. 
For the sake of comparison, the size of one of the 
largest leaves of the same kind of Sunflower that grew | 
in the garden is represented at D, in one-eighth of its 
natural dimensions. 
Nothing can be more striking than the influence of the 
nitrate on the growth of this plant, as exhibited in this 
experiment. The plants A and C are mere dwarfs, al- 
though both carry small and imperfectly developed flow- 
ers. The plant D, on the contrary, is scarcely smaller 
than the same kind of plant growiny under the best con- 
ditions of garden culture. Here follows a Table of the 
results obtained by the examination of the plants. 
=o ae <a 
. SB Fd 
S$} gs RS | acquired by the 
ed ss NS \plants in 86 days 
ssi | SS Sx of vegetation. 
See | 38 | 33 |————- 
SSS So. es | Nitro- 
Ess | &S§ OB | Carbon.| gen. 
cubic 
. grm. cent. mm. . 
A—nothing added to the soil......... 3.6 0.285 2.45 oud 60033 
C—ashes, phosphate of lime, and bi- | 
carbonate of potash, added to the 1 
BOL sa: disse ake bemioptncandamain ata ha 4.6 | 0.891] 3.42 | 0.156 | 0.0027 
D—ashes, phosphate of lime, and ni- | | | 
trate of potash, added to the soil..| 198.3 21.111 | 182.00 | 8.444 | 0.1666 
We gather from the above data: 
1. That without some compound of nitrogen in the soil 
vegetation cannot attain any considerable development, 
notwithstanding all requisite ash-ingredients are present 
