142 VIGNETTES FROM INVISIBLE LIFE. 



transparent cone -like elevation, there is no more 

 the appearance of life than even in Vesuvius itself, 

 with its rugged sides and vomiting crater. 



On the principle that "where there is smoke 

 there must be fire," we now seek for the hidden 

 cause of this singular phenomenon, this inrush of 

 water and its rapid propulsion from an apparently 

 inert mass of matter. As we cannot see through or 

 beneath this thorny filmy covering, recourse is had 

 to the knife, and by cutting it open or taking thin 

 slices for minute examination with high powers, 

 the mystery is unravelled. Here in the interior are 

 seen small circular chambers and channels, opening 

 outwards and leading inwards, in every direction 

 through the entire Sponge body, all converging in a 

 central large cavity or chamber, and thence up and 

 through the membranous tubular elevated vent. 

 Through all these mazy labyrinths the current is. 

 flowing with ever-increasing force to its final out- 

 flow. 



Increasing the magnifying power, and retracing 

 our steps, so to speak, along the passages and 

 chambers of this singular structure with our now 

 more powerful vision, the hitherto invisible agency 



