322 



in flower the clover was mown (May 24th). A square 

 ruthe was measured from each of the experimental plots, 

 and the clover separately cut and weighed. 



Calculated per Prussian morgen ( -f of an acre), 

 the results were, 



Cwts. of clover-hay 

 per morgen . 



Without manure 21-6 cwts. 



With gypsum 30*6 " 



With sulphate of magnesia 32'4 ' 



On a closer examination of the clover-hay it was 

 found that the increase in the crops obtained from the 

 plots manured with the sulphates did not extend equally 

 to all parts of the plant, but was more particularly ob- 

 servable in the production of stems. There were found 

 in 100 parts of the clover from the manured plots more 

 stems, fewer leaves, and still fewer flowers, than in 100 

 parts of the unmanured clover. 



Manured Manured 

 Unmanured. with with sulphate 

 gypsum, of magnesia. 



100 parts of clover-hay, flowers 17'15 11-72 12-16 



" leaves 27'45 26-22 25-28 



stems 55-40 61'62 63'0 



or, 



Flowers. Leaves. Stems. 



Clover-hay, unmanured 17-15 27-45 55-40 



" manured with gypsum 11*72 25-28 63'0 

 " " sulphate of 



magnesia 12-16 26-22 61-62 



These proportions of the different organs of the 

 clover plant show that the action of the sulphates has 

 led to a very considerable increase of the wood-cells, 

 or, in other words, to an extension of the stems at the 

 expense of the flowers and leaves. The relative propor- 

 tion of the flowers, leaves, and stems, was : 



Flowers. Leaves. Stemp. 



Clover-hay, unmanured 100 : 160 : 323 



" manured with gypsum 100 : 216 : 507 

 " " sulphate of 



magnesia 100 : 216 : 538 



According to the law of the symmetrical develope- 

 ment of plants, we may, without risk of error, take it 



