256 PRINCIPLES OF GARDENING. [CH. VIII. 



or incomplete formation of the foliage, preceded by 

 an imperfect production of the fibrous roots. 



The following experiment I consider as very de- 

 cisive : it was made in the year 1830, in my garden at 

 Great Totham, in the coimty of Essex. The soil in 

 this case, and in all others that will be stated here- 

 after, unless otherwise specified, is light, deep, 

 moderately fertile, resting on a substratum of sili- 

 cious gravel, and is constituted as follows : 



Water 30.5 



Stones and coarse sand , . . . 15.5 



Vegetable fibres 5 



Saline matters 4.5 



Oxide of iron 2.5 



Carbonate of lime 17.5 



Decomposing matter 7 



Alumina 15 



Silica 102.5 



200 



The variety employed was the early Shaw. An 

 equal number of whole moderately-sized potatoes that 

 had been treated in three different modes, were 

 planted the last week of March. No. 1! Twenty 

 sets that had been carefully kept cold and diy through- 

 out the mnter, firm, unshrivelled, and with scarcely 

 any symptoms of vegetation. No. 2. Twenty sets 



