BULLETIN OF THE BUSSEY INSTITUTION. 55 
The weight of the three buckwheat seeds planted, as deduced from 
the mean of a number of weighings, was a little more than 0.06 gramme. 
If, for the sake of comparison, we call the weight of the crop ob- 
tained from the ashes by water alone = 1, then the weight of the 
other crops will be respectively as follows :— 
Comparative yield 
the jer Chemicals employed. eee ie vee 
alohe = 1. 
8 Nitrate of lime and phoephste of. potash, *..... 15.16 
3 Nitrate of lime . . 7 15.00 
Nitrate of lime, nitrate ‘of. potash, ‘sulphate of 
11 11.66 
magnesia, and phosphate of potash - 
Nitrate of lime, sulphate of crmsetal Hee and phos- 
10 11.55 
phate of potash . ea ai ee ; 
6 Nitrate of ammonia - es 9.33 
4 Nitrate of potash and sulphate of magnesia ade 8.00 
1 RMNIMEIRATE OR) we Seyi ve (16 8 5 Byte 7.17 
7 Phosphate of potash oes , 1.50 
9 Sulphate of magnesia and phosphate of potash « 17 
2 Sulphate of magnesia. . . i 1.06 
5 AS Ae aa tame 1.00 
Experiments like these are almost. inevitably exposed to a variety 
of accidents, such as the failure of some seeds to germinate, and the 
occasional death of a young plant at the critical moment when support 
from the seed ceases and the plant is thrown upon its own resources. 
In general, results obtained in this way must be looked upon as ap- 
proximations to the truth, rather than as absolutely correct. But sev- 
eral of the results above tabulated are very striking. It is plain that 
the ashes used must have contained appreciable quantities of potash 
and phosphoric acid, as well, of course, as the lime, magnesia, sul- 
phuric acid, and iron which are necessary for the growth of plants ; for 
on the addition of nitrogenized salts to the ashes abundant crops of 
buckwheat and of barley could be readily grown. The action of the 
nitrates is well marked, and beneficial, in every instance. The solu- 
tion of nitrate of lime, which was much richer in nitrogen than either 
of the others, gave a crop twice as large as that yielded by nitrate of 
potash, and the jar watered with nitrate of ammonia, though containing 
only two plants, produced more than that watered with nitrate of pot- 
ash, — apparently because it received a larger quantity of nitrogen. 
The addition of potash and phosphoric acid, as in jar No. 8, did little 
or no good, while sulphate of magnesia seemed to do harm. 
It remained to be seen whether the ashes were any better in respect 
