CONTINENTAL CULTIVATION OF CROP. 427 



That they be kept free from weeds, and the surface soil 

 stirred by hoeing. 



That they be allowed to remain in the ground until 

 November, as their increase is in greater proportion at the 

 later than at the earlier periods of their growth. 



M. de Gasparin stated that by sowing in January and 

 transplanting early in April, when the plants were thicker 

 than a man's finger, his crop had nine months for its deve- 

 lopment, instead of five or six when sown in the ordinary 

 manner ; and, that as they form a concentric ring about 

 every fifteen days, his plants had eighteen, whereas the 

 number formed in those grown in the usual way rarely 

 exceeds twelve while each succeeding ring or layer being 

 external to the one preceding it, its diameter and bulk 

 must increase in an increasing ratio, the last six being 

 more than equal to the twelve internal ones, and conse- 

 quently more than doubling the gross produce of the crop. 

 Some of his roots were of great size, but they appear to 

 have been exceeded by those cultivated in the rich vine- 

 growing districts on the banks of the Canal de Saint Gilles, 

 where one of the roots exhibited reached the enormous 

 weight of 132 Ibs. 



That these results are very far beyond what we in this 

 country obtain, or probably, owing to the difference in our 

 climates, are ever likely to arrive at, is very true. They 

 show us, however, what an enormous increase may be 

 obtained in farm crops by securing to them those condi- 

 tions of cultivation which are most conducive to their 

 development. The largest crops of the district referred 

 to, obtained by the ordinary method of cultivation, had not 

 previously exceeded 48 tons 2 cwts. to the acre ; and when 

 we recollect the enormous produce that has been obtained 

 at home from rye-grass exceeding 100 tons per acre by 

 suitable treatment, we should not despair of being able, at 

 all events, largely to increase the yield of our mangold 



