654 Field Fxperiments on the Fixation of Free Nitrogen. 
soil of this plot contained. It must be borne in mind that, as I 
will afterwards explain, I had not then in view the question of 
the fixation of free nitrogen. 
We now stand thus as regards these plots. It is proved 
tolerably clearly that they have no “ condition ” available for 
the growth of cereals, and, in fact, that they must be remarkably 
deficient in “ nitric ” nitrogen. Yet, I shall afterwards show 
that, without the addition of nitrogen in any form whatever, two 
of the plots produced four crops containing a notable quantity of 
nitrogen. 
The Italian rye grass plot. No. 22, was left untouched after 
harvesting, and it threw up an abundant crop of wild plants, 
including eight gorse plants, some briars, numerous grasses, two 
clovers, wild strawberries, bluebells, dandelions, and a number of 
others. In this state it remains. 
The two plots of greatest interest are the barley and the 
oats. These plots, for the next crop, were each dressed with 20 
cwt. per acre of basic slag, and forked and trenched eight inches 
deep, thereby exposing the subsoil, which in its turn was treated 
with basic slag at the rate of 20 cwt. per acre. In the one case 
the subsoil was merely loosened and moved by the fork, without 
being turned over. In the other case the subsoil was completely 
turned over eight inches deep, so that the basic slag must have 
then permeated the whole depth of 16 inches. It will be seen 
afterwards that the results of the next cropping were better in 
this case than in the former, where the subsoil was not turned 
over. 
We have now, in the autumn of 1888, two plots on a clay 
loam, prepared with a full dressing of basic slag, supplying 
abundance of phosphoric acid, lime, and magnesia. In this state 
they were left to weather during the winter, and until March 1 
of the following year. On a clay loam, whatever may have been 
its previous percentage of available potash, it is very probable 
that the disintegrating influence of the weather would produce 
more than sufficient of this plant-food. 
On March 1, 1889, spring beans were dibbled on the two plots. 
Nos. 23 and 24, in rows eighteen inches apart and nine inches 
between the seed. The plants throve well, save some that were 
destroyed by wire-worm. The grov\i;h on both plots was vigor- 
ous, and the plants were very handsome, showing a marked con- 
trast to the previous mean-looking cereal crops. A few field-peas 
thit were accidentally mixed with the beans also grew with great 
luxuriance. 
The crop on No. 23 was harvested between September 7 
and 19, and yielded, per acre, 37 bushels of grain, and 22| cwt. 
