370 



BOTANICAL GAZETTE 



[NOVEMBER 



concentrate was much darker than bog water. The material in 

 the concentrate all remained in solution. No precipitate appeared 

 and no incrustation was left in the beaker when the concentrate 

 was poured out. The toxicity of the distillate and of the con- 

 centrate was tested by growing Tradescantia cuttings in samples 

 of them. The concentrate proved to be more toxic than the un- 

 treated bog water, while root hairs developed as well in the 

 distillate as they did in Cedar River water. Samples of the 

 concentrate and of the distillate were saturated with solid 

 (NH4)2S04 and allowed to stand overnight. The distillate gave 

 no precipitate in any case, while the concentrate gave a much 

 heavier precipitate than did the untreated bog water. 



Since all samples of bog water tested had been found acid to 

 litmus and to phenolphthalein, tests of both the concentrate and 

 the distillate were made by titrating with N/2oNaOH, using the 

 same indicators. The acidity of the concentrate was in every 

 case found to be greater than that of untreated bog water. The 

 distillate was slightly acid, but much less so than the untreated 

 water. The precaution of removing the CO2 by boiling before 

 titrating was taken in each case. Since both the concentrate 

 and the untreated bog water are colored solutions, the use of 

 indicators with them is unsatisfactory, and more exact means 

 would have to be used in order to get quantitative data. Table 

 I summarizes most of these results, together with some presented 



TABLE I 



later in the paper. The letters A, B, and C indicate relative 

 acidity, A being greater than B, while C is much less than B. 



Work was next undertaken to secure data on the chemical 

 constitution of the materials in solution in the bog waters that 

 had been experimented on and to get some indication as to what 



