CH. II.] THE ROOT. 8:1 



of seed : but, for the production of those plants whose 

 foliage is the part in request, as spinach, or of edi- 

 ble bulbous roots, as onions, which have a small 

 expanse of leaves, so as to be almost entirely de- 

 pendent upon the soil for nourishment, there can 

 scarcely be an excess of decomposed matter presented 

 to their roots. Spinach, on rich soils, will yield sue- ( 

 cessive cuttings ; the same as asparagus : the latter, 

 especially, demands abundant applications of nou- 

 rishment to its roots ; since, like the onion, it has 

 little foliage and slightly fibrous roots, at the same 

 time that, like the spinach, it has to afford re- 

 peated cuttings ; and thus, requiring a repeated deve- 

 lopement of parts, it needs abundant food in its im? 

 mediate neighboui'hood. 



A soil with a just proportion of decomposing matter, 

 will be capable of absorbing moisture during the 

 droughts of summer from the atmosphere, for the 

 most fertile soils are always the most absorbent, yet 

 it must not be too retentive of moistui'e, which is 

 the case in such soils as contain too much alumina ; 

 neither must it too easily part with moisture, a fault 

 which is a characteristic of those soils which contain 

 an excess of silica. A subsoil of gravel mixed with 

 clay is the best, if not abounding in oxide of iron, for 

 clay alone retains the moistui'e on the arable surface 

 in too great an excess ; and sand, or chalk, on the 

 contrary carries it away too rapidly. It is, however, 



G 2 



