2o8 Proceedings. 



The filter is made in the form of a candle, and the 

 suspended matter deposits itself on the outside surface, the 

 water being forced through the walls of the candle (which 

 is hollow) runs out of the orifice or tube connected with the 

 interior : the suspended matter is thus left as a slimy- 

 deposit on the surface of the candle to the thickness of yVth 

 to an |th of an inch. This deposit, when washed off, pro- 

 duces an almost black liquid, the black substance from 

 which settles to the bottom, as a black mud in appearance, 

 but on being shaken up rises in the liquid as black clots, 

 which soon break up and distribute themselves equally 

 throughout the water." 



