37 



Last year I wrote : " Phosphoric acid produces the largest increase 

 then come nitrogen and potash in the order named. The differences 

 are, however, small ; and the increase is, in no case, sufficient to pay 

 for the fertilizer. Barnyard manure does much better than 'complete 

 fertilizer', which indicates a more general exhaustion than the latter 

 can meet, or a beneficial physical, or chemical effect from the 

 manure." These statements, except as to the amounts of the " dif- 

 ferences " and the failure to "pay for the fertilizer" are exactly 

 true of the results of this year. Phosphoric acid and nitrogen, how- 

 ever, produce larger increases than last year, and more than enough 

 to pay for the material used. The influence of potash upon the yield 

 of stover is marked. With a far smaller increase in corn from use of 

 potash than is due to use of nitrogen^ we find a larger increase in 

 stover. 



Both lime and plaster, this year, appear to have produced a 

 profitable increase in crop. This was not true last year. The simi- 

 larity of these results to those obtained in Freetown, also upon a very 

 poor soil, has been already pointed out. 



In view of the results of our two years' work upon this soil, it may 

 be doubted whether a very profitable culture of corn upon it with 

 fertilizer is possible. Still by introduction of clover in rotation, as 

 a conserver of nitrogen, and the use of bone meal, fish, or similar 

 materials with a little lime and potash to help out the clover as well 

 as the corn, I should try it, were the land my own. 



With such barnyard manure as was used in this experiment I think 

 it would pay to use a plain super-phosphate on this soil ; and for 

 stover a little potash should be added. 



