174 OBSERVATIONS ON THE MEANS OF 



temperature in which the native crab scarcely shows signs of life ; and 

 its fruit acquires a degree of maturity, even in the early part of an 

 unfavourable season, which our native crab is rarely, or never seen to 

 attain. 



Similar causes are productive of similar effects on the habits of culti- 

 vated annual plants ; but these appear most readily to acquire habits of 

 maturity in warm climates ; for it is in the power of the cultivator to 

 commit his seeds to the earth at any season ; and the progress of the 

 plants towards maturity will be most rapid, where the climate and soil 

 are most warm. Thus, the barley grown on sandy soils, in the warmest 

 parts of England, is always found by the Scotch farmer, when introduced 

 into his country, to ripen on his cold hills earlier than his crops of the 

 same kind do, when he uses the seeds of plants, which have passed 

 through several successive generations in his colder climate; and in 

 my own experience, I have found that the crops of wheat on some 

 very high and cold ground, which I cultivate, ripen much earlier when 

 I obtain my seed-corn from a very warm district and gravelly soil, 

 which lies a few miles distant, than when I employ the seeds of the 

 vicinity. 



The value, to the gardener, of an early crop, has attracted his attention 

 to the propagation and culture of the earliest varieties of many species of 

 our esculent plants ; but in the improvement of these he is more often 

 indebted to accident than to any plan of systematic culture ; and contents 

 himself with merely selecting and propagating from the plant of the 

 earliest habits, which accident throws in his way ; without inquiring from 

 what causes those habits have arisen : and few efforts have been made to 

 bring into existence better varieties of those fruits which are not generally 

 propagated from seeds, and which, when so propagated, of necessity 

 exercise, during many years, the patience of the cultivator, before he can 

 hope to see the fruits of his labour. 



The attempts which I have made to produce early varieties of fruit 

 are, I believe, all that have yet been made ; and though the result of 

 them is by no means sufficiently decisive to prove the truth of the 

 hypothesis I am endeavouring to establish, or the eligibility of the 

 practice I have adopted, it is amply sufficient to encourage future 

 experiment. 



The first species of fruit, which was subjected to experiment by me, 

 was the apple ; some young trees of those varieties of this fruit, from 

 which I wished to propagate, were trained to a south wall, till they pro- 

 duced buds which contained blossoms. Their branches were then, in the 



