from Water exposed to Light. 231 



in abundance, convinced me that, at that period, it con- 

 tains nothing that can possibly be supposed to be of a 

 vegetable nature. The colouring matter of the water is 

 evidently of an animal nature, being nothing more than 

 the assemblage of an infinite number of Very small, ac- 

 tive, oval-formed animalcules, without anything resem- 

 bling tremella, or that kind of green matter, or water 

 moss, which grows upon the bottom and sides of the 

 vessel when this water is suffered to remain in it for a 

 considerable time, and into which Dr. Ingen-Housz 

 supposes the animalcules above mentioned to be actu- 

 ally transformed. 



But having finished the account of my experiments, I 

 shall finish this paper, not daring to venture conjectures 

 upon a subject so intricate in itself and so new, and upon 

 which the ablest philosophers of the age seem to be so 

 much divided in opinion. 



