118 ON THE FOOD OF PLANTS. 



" introduced into strong solutions of sugar, mu- 

 " cilage, tanning principle, jelly, and other sub- 

 " stances, died ; but that plants lived in the same 

 " solutions, after they had fermented. At that 

 " time I supposed that fermentation was neces- 

 " sary to prepare the food of plants, but I have 

 " since found that the deleterious effects of the 

 " recent vegetable solutions were owing to their 

 " being too concentrated; in consequence of 

 " which, the vegetable organs w r ere wholly clog- 

 " ged with solid matter, and the transpiration of 

 " the leaves prevented. The beginning of June in 

 " the next year, I used solutions of the same 

 " substances, but so much diluted, that there was 

 " only about one two-hundredth part of solid ve- 

 " getable matter in the solutions. Plants of 

 " mint grew luxuriantly in all these solutions, 

 " but least so in that of astringent matter. I 

 " watered some spots of grass in a garden, with 

 " the different solutions of jelly, sugar, and mu- 

 " cilage, which grew most vigourously, and that 

 " watered with the solution of tanning principle, 

 " grew better than that watered with common 

 " water. 



Again, " Mucilaginous, gelatinous, saccharine, 

 " oily, and extractive fluids, and solutions of 

 " carbonic acid in water, are substances that in 

 " their unchanged states contain almost all the 



