■J 



6 ANIMALCULA OF INFUSIONS. I. 



As I have repeatedly fpoke of ifolating ani- 

 malcula, or the method ufed of confining one in 

 a watch-glafs, on purpofe to obferve the fuccef- 

 five degrees of divifion, the reader will naturally 

 be earnefl to learn the mode employed, much 

 more fo if he is accuflomed to fuch matters, and 

 knows the extreme difficulty of obtaining one 

 alone in a drop of infufion, however fmall. 

 SaufTure himfelf ftates it as exceedingly difficult, 

 and that by dint of patience he fucceeded in con- 

 fining one in a drop of water ; and I mufh con- 

 fefs it was a great labour before I fell on a ready 

 method. A drop of infufion is conveyed into a 

 watch-glafs with the point of a pen ; it is of no 

 confequence although abounding with animalcu- 

 la : a drop of water is put two or three lines 

 from the firfl, and they are made to communi- 

 cate by a little channel formed by drawing out 

 the circumference of the drops. The animalcula 

 are not flow in traverfing the channel, and arrive 

 one after another in the drop of v/ater. Obferv- 

 ing this paflage with a magnifier, whenever I fee 

 an animalcule enter the water, I cut oiF the com- 

 munication with a hair pencil : thus imprifoning 

 a fingle animalcule. If more than one are to be 

 confined, it is eafy to allov/ any number to enter 

 the drop. The infufion being then taken away, 

 only one remains in the watch-glafs, or more if I 

 choofe it. 



I 



