$9.15 $4.59 $5.90 $0.58 



It is shown by this statement that satisfactory net profits 

 were made, and that not merely on the average of 2 or 3 

 years, but on the mean of 6 or 8 years. You see, further, 

 that in all cases by far the highest net profit was obtained by 

 the complete dressing, that is to say by fertilizing with phos- 

 phoric acid, potash and nitrogen. If potash was omitted from 

 the complete fertilizer, the net profit fell, on the average still 

 more, but if the nitrogen was omitted from the complete 

 dressing, the net profit fell, and that without any exception, 

 to the greatest extent by far. In the mean of all the experi- 

 ments, and of all the years, the net profit obtained, calcula- 

 ted per annum and per acre was : 



$9.15 when the complete dressing was given; 

 5.90 when the potash was omitted from the complete dressing; 

 4.59 when the phosphoric acid was omitted from the complete dressing; 

 .58 when the nitrogen was omitted from the complete dressing. 



This shows that what has been already pointed out, is 

 correct. All of the soils employed for our experiments (in- 

 cluding those dressed with farmyard manure) have allowed 

 the plants to hunger in the first degree for nitrogen, in the 

 next for phosphoric acid and then potash. Without an addi- 

 tional application of nitrogen, the potash and phosphoric acid 

 fertilizers could not work effectively. Without a supplemen- 

 tary application of Nitrate of Soda, no net profit, on the aver- 

 age was obtained. That is, complete fertilizer brought an 

 average net profit of $9.15 per acre; without nitrogen this 

 was reduced to 58 cents. It may be taken as a rule, that 



