ICO ANIMALCUI.A OF INFUSIONS, I. 



the experiment, I found it perfeclly ti'ue. A 

 dark cineritious pellicle covers the furface of 

 urine that has been feme time at reft ; and here 

 are the animalcula generated. They are of a 

 roundifh figure, and in fize like animated 

 points ( I ). The fame race of animalcula always 

 continues in urine, kept feveral months ; but no 

 new fpecies ever appears. One might fufpeft, 

 that they are produced after the urine has loft 

 its acrid and corrofive principle : but, befides re- 

 taining the chara6:eriftics of real urine, it is ftill 

 fatal to other animalcula ; nor do thofe of ftale 

 urine die v^hen put into that v/hich is recent. 

 Therefore this fpecies muft be eifentially different 

 from common infufion animalcula. 



It is well known, that the eleftric Ihock kills ani- 

 mals ; and as they are fmaller, fo are they more 

 eafily killed. A battery ten feet fquare with diffi- 

 culty kills a cat or a dog (2)5 but very few feet is 

 enough for a pigeon ; lefs for a goldfinch or canary ; 

 and thus diminifliing as the animals are fmaller. 

 It appeared that a fhock of moderate flrength 

 would deflroy animalcula ; but not being poffefT- 

 ed of an electrical machine, I availed myfelf of 

 the affiftance of Sig. Pietro Mofcati, then my 

 colleague in the royal univerfity of Pavia, who, 



in 



( I ) Leeuwenhoeck thinks he faw animalcula in the re- 

 cent urine of a mare, De ortu et defluvio capillorum, — T. 

 (2} Prieilley. Hiftory of Ekarlcity. ' 



