180 VIGNETTES FfiOM fNVTSIVLE LTFE. 



V 



To answer such an objection one might at first 

 admit the imputation, and be in harmony with the 

 general impression on this subject. But we prefer, 

 on the contrary and this for a special purpose to 

 go behind the objection in order to answer it, and 

 in so doing to ask the very old and oft -repeated 

 question, not " What is invisible life ? " but " What 

 is life?" for it seems necessary to have some 

 notion of the thing itself before saying anything of 

 its qualities. Should we be surprised if told that 

 all life is invisible ? That, however, seems to be 

 the case, though, of course, it was not with this idea 

 that these sketches were commenced, or in this 

 sense that they were named " Invisible Life." The 

 Sponge before alluded to affords a good illustration 

 of the idea here sought to be conveyed ; and whether 

 happily or not, it has been the immediate agent in 

 suggesting it in this connection. In the Sponge we 

 see with our naked eye almost as much as with the 

 microscope, so far as its exterior is concerned, yet 

 no sign of life appears. There is the dull, opaque, 

 immobile mass of matter, but no visible action no 

 locomotion ; not even is any organisation visible. 

 The mystery of its being, its living activities, are 



