174 



PROCEEDINGS OF THE CHEMICAL DEPARTMENT. 



probability is that differences quite equal to those between the 

 two periods would have been observed. The roots, however, 

 have changed in composition, and have become much more simi- 

 lar to the stalks than they w T ere before. Leaves and flowers are 

 also identical in composition, except that the latter contained a 

 somewhat smaller quantity of ash. The mineral matters have 

 also undergone some curious changes. Thus the absorption of 

 lime has scarcely been so rapid as in the former stage, for while 

 the weight of the plants has increased more than six-fold, that of 

 lime is only four times as large as it was on the 1st June. On 

 the other hand the absorption of potash and phosphoric acid has 

 been exceedingly rapid, the quantity of the former being twelve, 

 and of the latter ten times as large as it was before. The in- 

 creased amount of soda both as such, and in the state of chloride 

 of sodium, is also very remarkable. 



3rd Stage, 1st August, 1864. 



During this period the progress of the plants was very rapid, 

 for they advanced from 18 inches to an average height of 37 

 inches, and increased to three times their previous weight. 

 The flowers were now fully developed, and a number of pods 

 about an inch to two inches in length had begun to form. 

 These were separated and weighed apart, and the results for a 

 hundred plants were in grains : — 



211,150 



The weight per acre of the produce at this stage was, there- 

 fore, in lbs. : — 



