iqiq] RIGG & THOMPSON— BOG WATER 373 



was applied to other portions of this residue. The results were 

 negative in every case. The solubility of this residue was then 

 tried. It dissolved readily in cold Cedar River water. Solution 

 was complete in a volume of Cedar River water equal to the 

 volume of bog water from which the solid matter was obtained. 

 The toxicity of this solution of solids in Cedar River water was 

 tested by growing cuttings of Tradescantia in it, with other cut- 

 tings in bog water and Cedar River water as controls. The bog 

 water and the solution of bog sohds greatly reduced root hair 

 development on the cuttings, while root hairs developed abun- 

 dantly on cuttings in Cedar River water. The water solution of 

 this residue was found to reduce Fehling's solution slightly. 



The brownish residue was found to be insoluble in alcohol and 

 gasoline. In all cases but one it was also found entirely insoluble 

 in ether. In this one case enough went into solution to impart a 

 brownish color to the porcelain dish in which the ether was allowed 

 to evaporate. When bog water was shaken with an equal volume 

 of ether in a separator y funnel nothing was extracted from it. 



An attempt was made to throw out the solid matter in bog 

 water by centrifuging it. Samples were centrifuged for 20 minutes 

 at 1800 revolutions, but no solid matter at all was thrown out. 



Discussion 



The experimental data furnish evidence as to the substances 

 present in the water of sphagnum bogs, and also certain indications 

 in regard to the colloidal state of the soil solution in them and the 

 relation of this colloidal material to the toxicity of the water. 

 They have also a considerable bearing on agricultural utilization 

 of these areas. 



The large amount of organic matter in bog water as compared 

 with lake water is clearly shown by the large amount of solid 

 matter and the loss sustained when this solid matter is heated to 

 full redness. The sohd matter in bog water is 146 per cent of 

 that in lake water. The sohd matter from bog water lost 74 per 

 cent of its weight on ignition, while that from lake water lost only 

 30 per cent. That this organic matter is still in a very limited 

 state of oxidation is indicated by the large amount of oxygen that 



