182 ON THE ONION. 



measure, the bulb; and the quantity accumulated, as well as the period 

 required for its accumulation, varies greatly in the same species of plant, 

 under more or less favourable circumstances. Thus the onion, in the 

 south of Europe, acquires a much larger size during the long and warm 

 summers of Spain and Portugal, in a single season, than the colder 

 climate of England ; but under the following mode of culture, which I 

 have long practised, two summers in England produce nearly the effect 

 of one in Spain or Portugal, and the onion assumes nearly the form 

 and size of those thence imported. 



Seeds of the Spanish or Portugal onion are sown at the usual period 

 in the spring, very thickly, and in poor soil ; generally under the shade 

 of a fruit-tree ; and in such situations the bulbs, in the autumn, are rarely 

 found much to exceed the size of a large pea. These are then taken 

 from the ground, and preserved till the succeeding spring, when they are 

 planted at equal distances from each other, and they afford plants which 

 differ from those raised immediately from seed, only in possessing much 

 greater strength and vigour, owing to the quantity of previously generated 

 sap being much greater in the bulb than in the seed. The bulbs, thus 

 raised, often exceed considerably five inches in diameter, and being more 

 mature, they are with more certainty preserved, in a state of perfect 

 soundness, through the winter than those raised from seed in a single 

 season. The same effects are. in some measure, produced by sowing the 

 seeds in August, as is often done ; but the crops often perish during the 

 winter, and the ground becomes compressed and saddened (to use an 

 antiquated term) by the winter rains ; and I have in consequence always 

 found that any given weight of this plant may be obtained, with less 

 expence to the grower, by the mode of culture I recommend, than by 

 any other which I have seen practised. 



XIX. ON POTATOES. 



[Read before the HORTICULTURAL SOCIETY, February 6, 1810.] 



IN a paper lately read before the Society, I described a method of 

 cultivating early varieties of the potato, by which any of those, which 

 do not usually blossom, may be made to produce seeds, and thus afford 

 the means of obtaining many early varieties. I also offered a conjecture, 

 that varieties of moderately early habits, and luxuriant growth, might 

 be formed, which would be found well adapted to field-culture, and be 



