GRASS GROWING FOR PROFIT 23 
hay was produced. The influence of the phosphoric 
acid and potash was much less marked in all in- 
stances. When Nitrate of Soda was. doubled with- 
out increasing the acid phosphate or the muriate of 
potash the apparent increase in yield was more than 
doubled, but when the phosphoric acid was doubled 
without increasing the Nitrate of Soda or the muriate 
of potash the yield was decreased. (See cut on pre- 
ceding page.) 
RHODE ISLAND EXPERIMENT STATION. 
Bulletin 104. 
“ Some readers of this Bulletin will recall the rabid attacks 
upon Experiment Station chemists made a few years ago in 
the agricultural press by the late Andrew H. Ward, of Boston, 
in which he denounced the chemists for not giving the same 
recognition to soda as to potash as a manure, upon the ground 
of its alleged ability to replace potash in plant production. 
To such as may have known of those published criticisms, the 
verdict against the equality of soda in plant production 
returned in this experiment by the plants themselves, ought 
to remove any further doubt concerning the merits of the 
case. It can not be disputed, however, that soda is of some 
use in some manner with many varieties of plants, when the 
supply of potash is quite limited, and also with at least a few 
varieties of plants even in the presence of a fairly abundant 
supply of potash. Whether sodium salts would be rendered 
useless with all varieties of plants if the supply of potassium 
salts were greatly increased is a point which is not as yet 
fully proved, nor is it fully clear as yet in just what manner 
the sodium salt has been helpful in this particular experiment. 
This is a question which will be considered later in connection 
with the chemical analyses of the crops. It may, however, be 
stated here that sodium salts seem to liberate at least phos- 
phoric acid and potash, so that under certain circumstances 
they may act as indirect manures. They also appear under 
