90 ON THE USE AND OFFICES 



out oxygene while the sun shmes, and m this 

 particular all naturalists and physiologists agree. 

 It was a maxim of the great Sir Isaac Newton, 

 that in all scientific investigations of the opera- 

 tions of nature, for the purpose of ascertaining, 

 establishing, and producing causes and effects, 

 substances should not be unnecessarily multi- 

 plied. 



If, then, in conformity with this, and as be- 

 fore explained, we suppose the food of plants to 

 be water, holding in solution carbonaceous mat- 

 ter, and that the roots take up this liquid, and 

 that plants have the power of decomposing it — 

 water being composed of oxygene and hydro- 

 gene — the hydrogene and carbon might be com- 

 pounded in different proportions with a portion 

 of oxygene, and formed into the different sub- 

 stances of the plant, and the remainder given 

 out as gas ; and then we have only to believe 

 that the leaves are essential to the process, and 

 the fact cited by Dr. Hales, that plants absorb 

 and dispose of water, will be sustained, and 

 many jarring opinions will be reconciled. 



Admitting that a plant receives food, to sus- 

 tain and extend itself, for the various purposes 

 required by nature, and that, in this respect, it 

 is similar to animals, may we not suppose, that 

 as no animal is known to appropriate the whole 



