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animalcules. Sight and smell would disgust any one 

 to drink a water full of these living creatures, which 

 is always dirty and coloured 



In order to investigate these animal aggregations, 

 the green gelatinous matter is collected in a glass, 

 with a wide orifice, into which we pour a little of 

 the water in which they lived, or, if not to be had, 

 river - water. 



The microscope, intended for these investigations, 

 must show the magnified objects clear and distinct. 

 MM. Pistorand Schiek, in Berlin, Plossl, in Vienna, and 

 Chevalier, in Paris, make the best instruments, which 

 magnify 1000 3000 times. Those which magnify 

 only 5 600 times, are unfit for such researches. A 

 particle of the green thermal substance, of the size of 

 a pin's head, is placed upon the object-glass, and 

 torn between two sharp instruments, or, if wanting, 

 with pins 5 and the green fragments are moistened 

 with a small drop of water. The observation begins 

 with magnifying 100 200 times, in order to detect 

 the most distinct forms. Has an animalcule been 

 discovered, it must rest some time under the instru- 

 ment. The observation must be repeated with a 

 magnification of 4 600; and after having acquired 

 some skill in the mode of magnifying, we continue 

 the intended investigation. 



After having acquired by numerous trials a certain 

 dexterity, the anatomy of the animalcules takes place 

 in two different ways. The first is plain and easy: 

 A flat bit of glass, as thin as paper, very pure and 



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