430 THE MANGOLD-WURZEL CROP. 



Professor Buckman's experiments, carried on at the 

 Royal Agricultural College (1854), comprised five varie- 

 ties of mangold, which were sown in the same soil at the 

 same time, and treated in every respect in the same way. 

 Two rows were sown of each sort; and when the plants 

 had attained the size of about 1| inch in diameter, one 

 row of each sort was closely stripped of all the outside 

 leaves, by cutting them carefully away with a sharp knife, 

 so as not to produce injury by tearing a process which 

 was from time to time repeated, as often as the outer 

 leaves had again attained a size to be used as a feeding 

 substance. The result of this treatment, at the time of 

 lifting and weighing the roots in November, is thus 

 given: 



Varieties. Leaves Intact. Leaves Cut. 



1. Red Globe, 31'0 23'5 



2. Yellow Globe, 45'0 18'5 



3. Long Red, 49'0 18'0 



4. Long Yellow, 35'5 18'0 



5. Long white, 32'5 19'5 



Total of. 193-0 97'5 



These results show that the average produce of the five 

 varieties tried was reduced just one-half by removing the 

 leaves from the plants while in a growing state, the most 

 productive varieties, the Yellow Globe and Long Red, 

 being those which suffered most by being deprived of 

 their leaves. 



These experiments of Professor Buckman were con- 

 firmed by those of Dr. Wolff, the professor of chemistry at 

 the Royal Agricultural College at Hohenheim (Wiirtem- 

 berg), who found that, by merely stripping the leaves off 

 for feeding purposes in September, and again in October, 

 the root produce was diminished one-fifth. This was not 

 the only loss the crop sustained by the practice ; for on 

 removing them to his laboratory, and making a compara- 

 tive analysis of their organic constituents, he found that a 



