444 BOARD OF AGRICULTUEE. 



the discussion. A careful consideration of the composition 

 of the ash obtained from fruits raised upon the unfertilized 

 phit (IV.), as compared with any of those obtained from 

 fruits raised upon the fertilized plats, cannot fail to lead to 

 the conclusion, that the unfertilized soil contained an ample 

 supply of available phosphoric acid, magnesia, soda and 

 iron ; for even an actual addition of these important plant 

 constituents, in the form of fertilizer, to the soil of Plats I., 

 III. and v., failed to increase the quantity of these constitu- 

 ents above that found in the ash of fruits raised upon the 

 unfertilized plat. The only ash constituent in which the 

 unfertilized soil seems apparently to have been deficient, is 

 available potassa. 



An addition of potash compounds to the soil has in every 

 instance increased the percentage of potassa in the fruits, 

 varying from six to eleven and more per cent. The fruit 

 gathered from Plat V. showed the most remarkable diifer- 

 ence in that direction. Potash fertilizers have decidedly 

 improved desirable qualities in the fruits ; those from Plat V. 

 proved the most saccharine. 



Aside from the practical lessons which may be gleaned 

 from the above described experiment, there is another fea- 

 ture of the analytical results deserving a serious considera- 

 tion ; namely, the increase of potassa in the currants is 

 invariably accompanied by a correspondinrf decrease of phos- 

 phoric acid, and of lime in particular. This result coincides 

 with my previous observations concerning the action of 

 potash fertilizers on grapes, strawl)erries and peaches. 



The circumstance that the most striking alteration in the 

 mineral constituents of the currants has been produced by 

 muriate of potash, seems to bo of particular interest in con- 

 nection with some of my previous experiments regarding the 

 effects of that potash compound on diseased peach trees. 



The examination of fruits and of young branches from 

 peach trees affected by 



" The Yellows'' 



disclosed the fact that they contained a large amount of lime, 

 and more phosphoric acid than fruits and young branches 

 collected from healthy peach trees of the same variety. 



