296 BULLETIN OF THE BUSSEY INSTITUTION. 
to be of remarkably constant composition and is probably really 
better adapted for my experiments than distilled water would be, 
in view of the difficulty of freeing the latter from ammonia com- 
pounds and of obtaining large quantities of it in a state of abso- 
lute purity. 
After numerous trials with other plants, I finally chose buck- 
wheat as a proper plant for the assay, since it has tolerably small 
seeds, grows quickly, can live in very poor soils and is better 
able than many other plants to support the hardships incidental to 
confinement and partial starvation. 
The sands and earths, excepting those which had been calcined, 
as will be explained hereafter, were always taken in the air-dried 
condition. And in all cases the crops were dried at 90° to 100° C. 
upon a steam table. 
A record of some of the results actually obtained will serve 
better than anything else to exhibit the limitations of the process.* 
For example, the results of trials made with loams admixed with 
sand and, for the sake of comparison, with pure loams were as 
follows : — 
Trials with loam alone. Each jar contained 2 kilos. of loam from the specified locality. 
Pe The crops from PLAIN-FIELD || The crops from Mr. APPLE- 
5 LOAM. TON’S LOAM. 
s Harvest; 17th Mayveh, 22.5 EE eee 
y 1873. 5 io hs set 
|The loams were watered AeA | nied il 4 y siste ar bt | yy, siste 
A with bbea t: ‘7 ee of how vee qin eer of how 
SrmMss |inches.| 8°&S: | many || 8™™* linches. | 5°€°* many 
plants. ‘ plants. 
1 | Nitrate ofpotash . .| 2.38 9-15 23 5 1.34 | 11-12 32 6 
2 | Sulphate ofmagnesia. | 3.36 14 25 3 2.15 | 11-16 29 6 
3 | Nitrate oflime . . .| 4.87 | 10-19 60 5 2.25 | 10-13 39 7 
4 | Nitrate of potash and 
sulphate ofmagnesia | 4.40 | 13-17 44 5 2.49 | 11-14 48 5 
5 | Rain-water . . . .| 3.60%; 13-21 62 5 2.19 8-17 25 5 
6 | Nitrate of ammonia .| 3.13 | 14-16 28 4 1.89 9-16 34 5 
7 | Phosphate of potash . | 3.go | 12-14 37 2 4-14 | 11-15 22 6 
8 | Nitrate of lime and 2 
phosphate of potash | 8.97 | 17-23 70 5 5-13 | 11-15 65 3 
9 | Sulphate of magnesia 
and phosphate of pot- 
BSN ey eo cet bs eo la AsYOL | el o—al: 17 + 5.19 15 46 2 
10 | Nitrate of lime, sul- 
phate of magnesia, 
and phosphate of pot- 
ash ws + ee tf 989, ) 16-24 90 5 3-95 | 12-16 30 5 
11 | Nitrate of lime, nitrate 
of potash, sulphate of 
magnesia, and phos- 
phate ofpotash . .| 6.71 | 16-27 84 5 4-35 | 16-17 69 5 
* Details of some of the first trials with coal ashes, pit sand and green 
sand from New Jersey, have been given already in the Bussey Bulletin, 1. | 
50 and 2, 159. 
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