On the Roots differing in each SoJl. 325 



found closed and their sides pressed together. Tliere is still, 

 however, much to be discovered in the mechanism of the water 

 plants, which I hope to understand and imravel this summer : 

 the straight roots of the real water plants are never branched, 

 nor have they any radicula, fibres, and rarely any hairs, and 

 those only on the middle root. I before showed that the leaves 

 take in no nourishment from the atmosphere ; but these pipes 

 hanging continually in water, and administering it to the plant 

 as long as the light continues, must give all the support they 

 can possibly require. 



Thus it may be easily seen that the roots as v.ell as the aiti- 

 cles of the leaves and the hairs confirm the facts they promised 

 to corroborate, and prove that the plants are either fed by the 

 roots or the atmosphere, or both conjointly; that this entirely de- 

 pends on the nature of the soil. What then is to be deduced 

 from this review of their habits ? That each plant being formed 

 to grow in one particular earth, it must conse()uently be more 

 adapted and grow better m its native soil than in any other. 

 That those plants which grow in sand, from taking so much 

 from the atmosphere, require a greater attention to be paid to the 

 aspect than any other ciraijnstance. That those which grow 

 in clayey ground demand its being drained, and reduced to as 

 fine a soil as is consistent with the nature of the earth ; that the 

 roots may be capable of running to a greater distance from their 

 centre root, without danger of having them cut off', and ihere- 

 fore that they may, by .spreading more, be better able to nourish 

 the plant. In calcareous ground the form of the root teaches 

 Tis that the weight of the chalk should be lessened by mixture, 

 and the secreted water mingled with the upper surface : and in 

 a rich soil it should be well ascertained, whether it is luscious 

 enough to do without manure ; as all these luxuriant j)lants are 

 so loaded with the means of taking in nutriment from the root, 

 that if any addition is made they will easily overpower them- 

 selves, and die of plethorV. It often happens that dung is laid 

 on land that would grow better for a few cart-loads of clay or 

 sand. I have seen a soil so rich as to spoil the taste of the ve- 

 getables raised in it, and to bring on disorders that afterwards 

 spread in the seed. It is greatly the interest of the farmer who 

 is lucky enough to have such land, to ascertain this, as it is only 

 not to manure it, and now and then to throw on it a little lime 

 to prevent the acid too strongly predominating over the alkali, 

 and the plants cannot fail to do well. It is astonishing iiow 

 much better the East Indians understand this subject than we 

 do : they would not put a plant in a wrong soil for the luorld. 

 They say very properly that it will ILight it, and they have al- 

 ways proved it ; for when Tippoo Saib insisted on their putting in 



X 3 a parti- 



