The Life of the Fly 



cess. Now the stocked pond will not be long 

 in filling itself with gases unfit to breathe, with 

 putrid effluvia and other animal refuse; it will 

 become a sink in which life will have killed 

 life. Those dregs must disappear as soon as 

 they are formed, must be burnt and purified; 

 and from their oxidized ruins there must even 

 rise a perfect life-giving gas, so that the water 

 may retain an unchangeable store of the 

 breathable element. The plant effects this puri- 

 fication in its sewage-farm of green cells. 



When the sun beats upon the glass pond, the 

 work of the water-weeds is a sight to behold. 

 The green-carpeted reef is lit up with an in- 

 finity of scintillating points and assumes the ap- 

 pearance of a fairy-lawn of velvet, studded 

 with thousands of diamond pin's-heads. From 

 this exquisite jewellery pearls break loose con- 

 tinuously and are at once replaced by others in 

 the generating casket; slowly they rise, like 

 tiny globes of light. They spread on every 

 side. It is a constant display of fireworks in 

 the depths of the water. 



Chemistry tells us that, thanks to its green 

 matter and the stimulus of the sun's rays, the 

 weeds decompose the carbonic acid gas where- 

 with the water is impregnated by the breathing 

 of its inhabitants and the corruption of the or- 



180 



