On the Cholera Animalcule. 157 



I have, for many years, made these minutest of organic bo- 

 dies the subject of my pai*ticular inquiries, and have for that 

 purpose employed the best instruments. But none before me, 

 nor have I myself, ever succeeded in finding in the air these 

 small bodies to which tradition had given a real existence. I 

 must, therefore, warn medical men from modes of treatment of 

 cholera founded upon this principle, for no naturalist has yet 

 observed these animalcules. I have never observed these ani- 

 malcules under the microscope, al the time of the plague in 

 Egypt and Siberia ; and previous to my African journey, in the 

 Hospital of the Charite at Berlin, I had examined with the mi- 

 croscope many contagious cutaneous eruptions, without having 

 ever seen them. While, by the most rigorous microscopic ac- 

 curacy, I have made the singular discovery, that infusory ani- 

 malcules, from Jth to g^^oo^l^ ^^ ^ li"^ ^^ size, possess an orga- 

 nization similar to many of the higher animals, and have de- 

 monstrated their propagation by eggs and internal organs, 

 which are less than juJ^n^^ ^^ ^ ^^^^9 ^^ ? 75^0 00^^ of an inch 

 in diameter, and are yet distinctly visible. 



What must, then, be the size of the pest or cholera animal- 

 cules, or cours de ventristes^ if they were not discernible by 

 such instruments ? The opinion is to be classed in the same ru- 

 bric with the traditions and hypotheses of dragons, &c., and has 

 at least been confirmed by the experience of no credible natura- 

 list. 



According to the observations of Professor Ehrenberg, the 

 so called " Priestley's Matter,"" when it is not formed by real 

 animals of a very different form, was by algae ; and particularly 

 when it appears as a pellicle or cuticle, is the result of putrefac- 

 tion, and only consists of the dead bodies of infusoria. It is 

 therefore not the commencement of new formations, but the re- 

 mains of dead organic generations. 



