350 Report oF THE HORTICULTURAL DEPARTMENT OF THB 
GENERAL DISCUSSION OF THE RESULTS. 
What is the testimony of these experiments on the question 
as to whether nitrogenous commercial fertilizers may be used 
with profit in forcing lettuce either with or without stable 
manure? The data which have already been presented will now 
be considered with reference to their bearing upon this question. 
RHSULTS FROM USING THE COMMERCIAL FERTILIZERS WITHOUT 
MANURE. 
Both on the sandy loam and on the clay loam, where no manure 
was used the addition of the commercial fertilizers resulted in 
a decided increase in yield over the untreated soil. On the clay 
Joam the nitrate of soda generally appeared to be more beneficial 
than either the dried blood or the dried blood combined with the 
nitrate of soda, and with one exception did equally as well or 
better than sulphate of ammonia. On the sandy loam it was 
not so beneficial as dried blood except with the first crop, when 
it proved somewhat better; but it proved superior to sulphate of 
ammonia except with the second crop. The use of lime with the 
nitrate of soda gave an improved crop on the sandy loam but 
decreased the crop on the clay loam. 
The results with sulphate of ammonia without manure were 
very variable with the different crops. On clay loam it was 
superior to both nitrate of soda and dried blood in the first crop 
and inferior to both in the last. On the sandy soil the results 
were also variable; in one instance it gave the highest yield with 
the crop of loose lettuce, and it was generally more or less 
superior to the nitrate of soda but inferior to dried blood. 
The dried blood when used without manure generally gave 
better results on the sandy soil but not so good results on the 
clay soil as the commercial fertilizers did with which it was 
compared. 
RESULTS FROM COMBINING THE COMMERCIAL FERTILIZERS WITH 
MANURE. 
When manure was applied in addition to the commercial fer- 
tilizers very much better crops were obtained than when the 
latter only were used. This is clearly shown in the following 
