VOL. XXI.] I'HILOSOPHICAI, TRANSACTIONS. 3()5 



That there is a great quantity of this matter in rivers, and that it contributes 

 vastly to the fertility of the earth, we have an illustrious instance in the Nile, 

 the Ganges, and other rivers that annually overflow the neighbouring plains ; 

 which thence show the fairest and largest crops of any in the whole world. 



7. Water serves only for a vehicle to the terrestrial matter which forms vege- 

 tables, and does not itself make any addition unto them. Where the proper 

 terrestrial matter is wanting, the plant is not augmented though ever so much 

 water ascend into it. The cataputia in e took up more water than the mint in 

 c, and yet had grown but very little, having received only 3^ grains of addi- 

 tional weight ; whereas the other had received no less than 26 grains. The 

 mint in i was planted in the same sort of water as that in k ; only that the 

 latter had earth dissolved in the water; and yet the former drew off 13140 

 grains of the water, gaining itself no more than 13Q grains in weight: whereas, 

 the other took up but 10731 grains of water, and was augmented 1 68 grains 

 in weight. Consequently the former spent 2409 grains more of the water than 

 this in K did, and yet was not so much increased in weight as this by 29 grains. 

 The mint in m stood in the very same kind of water as that in n, but the water 

 in M having much less terrestrial matter in it than that in a, the plant bore up 

 8803 grains, gaining itself only 41 grains, whereas that in n drew off no more 

 than 4344 grains, and yet was augmented 94 grains : so that it spent 4459 

 grains of water more than that did : and yet was not itself so much increased 

 in weight as that was by 53 grains. Tliis is both a very fair and a very conclu- 

 sive instance, that water is not the matter that composes vegetable bodies, but 

 only the agent that conveys that matter to them, that introduces and distributes 

 it to their several parts for their nourishment. 



This fluid is fitted for the office here assigned it several ways : first, by the 

 figure of its parts ; which, as appears from many experiments, is exactly and 

 mathematically spherical ; their surfaces being perfectly smooth, and without 

 any the least inequalities. So that it is evident, corpuscles of such a figure are 

 easily susceptible of motion, indeed far above any others whatever, and conse- 

 quently the most capable of moving and conveying other matter that is not so 

 active and moveable. Then the interstices between bodies of that figure are, 

 with respect to their bulk, of all others the largest, and so the most fitted to 

 receive foreign matter. Besides, as far as the trials inform us, the constituent 

 corpuscles of water are each singly considered absolutely solid, and do not yield 

 to the greatest external force, which secures their figure against any alteration ; 

 and hence the interstices between the corpuscles must be always alike. By the 

 latter it will be ever disposed to receive matter, and by the former, when once 



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