16 VIGNETTES FROM INVISIBLE LIFE. 



whole group doing this together, and almost in- 

 cessantly, causes it to roll over and over; so pro- 

 ducing the appearance of a sphere of transparent 

 and beautiful creatures, each one revolving on its 

 own account, and the whole revolving together in 

 perfect harmony. There is but one known species 

 of these creatures, and they are not found every- 

 where. But they are found in abundance, tens of 

 thousands of them together sometimes, in these 

 Walthamstow ponds. Can we then wonder that 

 there should be some anxiety lest one of their well- 

 known and easily accessible habitats should be 

 destroyed ! 



The microscopist dealing with things invisible 

 to ordinary vision, and consequently with forms of 

 matter with which the general public are unac- 

 quainted, labours under some disadvantage, appear- 

 ing to attach too much importance to such minute 

 objects ; but a little consideration will surely dispel 

 all such notions. The investigations of science 

 within the last few years have made it apparent 

 that our own welfare physical, mental, and com- 

 mercial depends considerably on the compara- 

 tively small and invisible forms of life with which 



