MANURING OF POTATOES. ZF 

season of 1899, than 10 tons dung with 64 cwts. artificials. 
By withholding each of thethree artificials in turn from the 
standard dressing (with dung) it was found that, while the 
addition of the complete mixture yielded somewhat the 
largest crop, it also yielded the smallest profit. Other plots 
were devoted to testing the effect of doubling the quantity of 
potash, superphosphate, or ammonia in the above standard 
mixture. Asa result, neither the omission of any one of 
these ingredients in the artificials added to ten tons dung, nor 
the doubling of them nad a marked effect on the crop. The 
heavier dressings gave uniformly higher yields, but when the 
value of the increase was compared with the extra cost the 
profits were found not to be sufficient to recommend the 
practice. The results were thus not encouraging to those 
who make a practice of applying large quantities of artificials 
along with farmyard manure; although the season was 
peculiar, and might have affected the results. 
On three plots no dung was given; one receiving to ewts. 
of mixed artificials showed an estimated profit over the 
unmanured plot of £2 2s. By omitting the superphosphate 
this profit was reduced to 12s. 3d., and dy omitting the potash 
a loss of 18s. 4d. was incurred. It is only when the use of 
farmyard manure is involved that there is any doubt as to 
the value of these artificials for manuring the crop. These 
last three plots were only included to emphasise the 
necessity for potash when dung is not applied. 
