SOILS, MANURES AND FERTILIZERS 21 
reason seems backward, or slower in growth than 
it should be, an application or two of nitrate of soda 
will often produce results almost marvelous. Be 
sure, however, that your troubles are not due to 
some mistake in temperature, ventilation or water- 
ing, before you ascribe them to improper or ex- 
hausted soil. 
Now, having had the patience to find out some- 
thing about the conditions under which plants ought 
to succeed, let us proceed to the more interesting 
work of actually making them grow. 
