120 
IX. Wollny (1882-83) made seven series of experiments, in each 
of which five or six tubs received daily different quantities of water, 
except only that in the driest tubs extra water was given for the 
first few days in order to insure the sprouting of the seeds, and 
except, further, that in the experiments of 1882 the water was given 
every second or third day instead of daily, whereby was brought about 
the rather large variations in the moisture of the earth. The tubs 
were shielded from natural rain, were of the same size, and had the 
same weight of earth and aliment. Nothing is said as to whether 
special manure or fertilizer was used, but only that all were treated 
perfectly alike except as to water; the effect of manuring was shown 
only in the case of Nos. 6 and 7 in that No. 6 was treated lke the 
previous ones, while No. 7 received a supply of mixed, Peruvian guano, 
superphosphate, and sulphate of lime, gypsum, or plaster equivalent 
to 526 kilograms per hectare. Exact measurements were made 
upon six plants in each tub in order to judge of the relative harvests. 
An abstract of Wollny’s measures is given in the following tables: 
EXPERIMENT OF 1882. 
Grain harvest dried in 
air. 
Mois- Mixed 
Tub. ture. | Sum- pares grain. 
mer | Beans.| . 
rye rape 
seed. 
anara| - ~ — 
1 | 100-80 4.3 9.2 2.4 11.0 
2 80-60 Date i Lien: 4.4 13.9 
3 | 60-40 | 5.1 | 11.6 | 4.9 1207 
4 | 40-20 3.9 3.3 z.0 | 9.4 
5 20-10 0.4 0.5 0.25 1.8 
EXPERIMENT OF 1883. 
| Grain harvest dried. 
| 
Mois- Summer rape seed. 
Tub. 
ture. Loe r- 
| bean.a ot 
| aod Warmed. 
1 100 eee | 0.2 | 0.3 
2 80 | 21.9 3.3 3.9 
3 60 | 14.0 4.2 4.3 
4 40 10.6 4.6 6.9 
5 re Ui 3355) 2.59 2.7 
6 10 1.3 0.8 1.4 
“A variety of English or Windsor beans (Faba vulgaris) raised in Europe for feeding 
horses. 
He concludes that, in general, the quantity of harvest is influenced 
to an extraordinary degree by the quantity of available water and 
much more than by any other factor of vegetation. In general the 
