r 



mint grew luxuriantly in all these solutions ; but least 

 so in that of the astringent matter. I watered some 

 spots, of grass in a garden with the different solutions 

 separately, and a spot with common water : the grass 

 watered with solutions of jelly, sugar, and mucilage 

 grew most vigorously ; and that watered with the so- 

 lution of the tanning principle grew better than that 

 watered with common water. 



I endeavoured to ascertain whether soluble vegetable 

 substances passed in an unchanged state into the roots 

 of plants, by comparing the products of the analysis 

 of the roots of some plants of mint which had grown, 

 some in common water, some in a solution of sugar. 

 1 2O grains of the roots of the mint which grew in the 

 solution of sugar, afforded five grains of pale green 

 extract, which had a sweetish taste, but which slightly 

 coagulated by the action of alcohol. 120 grains of 

 the roots of the mint which had grown in common 

 water yielded three grains and a half of extract, which 

 was of a deep olive colour ; its taste was sweetish, 

 but more astringent than that of the other extract, 

 and it coagulated more copiously with alcohol. 



These results, though not quite decisive, favour 

 the opinion that soluble matters pass unaltered into 

 the roots of plants ; and the idea is confirmed by the 

 circumstance that the radical fibres of plants made to 

 grow in infusions of madder are tinged red ; and it may 

 be considered as almost proved by the fact, that sub- 

 stances which are even poisonous to vegetables are ab- 

 sorbed by them. I introduced the roots of a primrose 

 into a weak solution of oxide of iron in vinegar, and 



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