TG STORRS AGRICULTURAL EXPERIMENT STATION. 
It will be noticed that the plots are arranged in groups. 
Upon those of the preliminary group the fertilizing ingredients 
are applied singly in plots 1—3, and two by two in plots 4—6. | 
The combination on plots 6, 6a, 6b, 6c, is designated as 
“mixed minerals,” and is used as a basis to which the nitrog- 
enous materials are added for the mixtures used upon all the 
plots of the succeeding groups. As the dried blood ‘has but 
little, and nitrate of soda and sulphate of ammonia have no 
phosphoric acid or.potassium, the quantities of these mineral 
fertilizers used are kept constant. By comparing the yields 
from the plots having “ mixed minerals ” alone, with the 
yields from the plots having nitrogenous fertilizers in addition 
to the mixed minerals, the effects of the nitrogen upon the yield 
may be learned. 
It will be observed, furthermore, that the preliminary group 
Nos. 1 — 5, with “ mixed minerals’ No. 6, and No. 7 of the 
nitrate of soda group are practically the same as Nos. A—G of 
the “ soil tests ” described above. 
In some of the experiments as actually made, the three 
numbers of the dried blood group (13, 14, 15) were replaced by 
mixtures in which nitrate of soda, sulphate of ammonia, and 
dried blood were used instead of dried blood alone. In several 
instances the preliminary group or one of the nitrogenous 
groups was omitted. So-called “nothing ” plots, 7. ¢., plots 
without any fertilizer, were provided before, between, and after 
the several groups. 
Special Nitrogen Experiments on Small Plots.— In the regu- 
lar special nitrogen experiments as in the soil tests, the in- 
dividual plots were generally one-tenth to one-twentieth of an’ 
acre each. A number of special nitrogen experiments with 
different species of grasses, however, were made in the grass 
garden of the Station. In most of these experiments the plots 
were quite small, being two square rods (one-eightieth of an 
acre) each, while a few were even smaller. The number of 
groups and of plots in a group was also reduced, so that there 
were generally only four plots in each group, comprising a 
nothing plot, a plot with mixed minerals, a plot with minerals 
and the one-third ration (25 lbs.) of nitrogen, and a plot with 
minerals and the full ration (75 Ibs.) of nitrogen. 
COST OF FERTILIZERS. 
In the calculations of the financial gains from the use of 
the fertilizers the present prices of fertilizing materials have 

