CONSERVATION OF THE SUGAR BEET. 



247 



such that the beets would be in danger. The outer 

 portions are also protected by a certain quantity of 

 earth, the thickness of which is variable. Another 

 type of silo, adopted some thirty years ago, was a first 



Fig. 52. 

 Vertical section- 



Half horizontal section. 



Conical silo, in tlie centre of ■which is a sort of chimney, can be 



closed with straw. 



step towards improvement. A ditch was dug having 

 about 1.20 m. (3.93 feet) in depth and 10 m. (32.80 feet) 

 in length, into which the beets were thrown, the whole 

 being then covered with earth. (See fig. 53.) The 

 shape given was that of a roof, the idea of which was 

 to cause the water resulting from rain to pass bej'ond 

 the silo. The results were negative. The principles 

 of ventilation were only partly understood. IN^ear each 

 extremity a certain quantity of straw was placed, 



