AN IMPROVED METHOD OF RAISING EARLY POTATOES. 257 



of their tuberous root : for the plants of those varieties always acquire a 

 considerable age before they begin to generate tubers, and therefore do 

 not too soon begin to expend themselves in the production of tubers ; and 

 the size which these acquire within any given period in the spring will be 

 to a great extent regulated by the strength of the plants, at the period 

 when they first spring from the soil ; and strong plants of such varieties 

 can be afforded only by sets of considerable size. I have, in consequence, 

 for some years past, selected in the autumn the largest tubers, and these 

 nearly of an equal size, for planting in the spring ; and I have found that 

 these not only uniformly afford very strong plants, but also such as 

 readily recover when injured by frost : for being fed by a copious 

 reservoir beneath the soil, a reproduction of vigorous stems and foliage 

 soon takes place, when those first produced are destroyed by frost, or 

 other cause. 



When the planter is anxious to obtain a crop within the least possible 

 time, he will find the position in which the tubers are placed to vegetate 

 by no means a point of indifference ; for these being shoots, or branches, 

 which have grown thick instead of elongating, retain the disposition of 

 branches to propel their sap to their leading buds, or points most distant 

 from the stems of the plants of which they once formed parts. If the 

 tubers be placed with their leading buds upwards, a few very strong and 

 very early shoots will spring from them ; but if their position be reversed, 

 many weaker and later shoots will be produced ; and not only the 

 earliness, but the quality of the produce in size, will be much affected. 



In the spring, when the young plants are just beginning to appear in 

 the rows, I have often found it very advantageous to raise the mould over 

 them in ridges by an operation perfectly similar to moulding the plants. 

 Protection has been thus given against frost, and I have not found the 

 period of maturity of the crop to have been in any degree retarded. 



It has been contended that there is much waste in the practice above 

 described of planting large sets ; because the old tuber is often found to 

 have lost little in weight, when an early crop is taken up in an immature 

 state : and it has thence been inferred, that a very small part only of the 

 matter of the old tubers enters into the composition of the new. But 

 I believe a false inference has in this case been drawn, and that, under 

 ordinary circumstances, a very large portion of the soluble matter of the 

 old tubers is employed in the formation of the new ; for I have proved 

 by experiments purposely made, that the vital union, and community of 

 circulating fluid, between the old tuber and the plant which has sprung 

 from it, is not so soon dissolved. 



