THE TOXICITY OF BOG WATER 
George B. Rigg 
The following is a brief statement of data obtained by the writer 
in experiments on waters from sphagnum bogs of the Puget Sound 
region and Alaska. The flora of these bogs has been previously 
described (6, 7). In most cases the water was collected by cutting 
a shallow cavity in the sphagnum and dipping up the water which 
accumulated within a few minutes. In a few cases during the dry 
season, water could not be obtained in this way. It was then obtained 
by squeezing it from handfuls of sphagnum obtained a few inches 
beneath the surface of the bog. Details of the experiments here re- 
ported as well as an account of other work on this water now in 
progress will be reported later. 
1. When they were filtered through filter paper, then saturated with 
NaCl, MgS04, Na2HP04, or (NH4)2S04 and allowed to stand over 
night the samples tested have all shown a precipitate. 
2. When this precipitate was filtered off and the filtrate dialyzed 
in a dialyzing tube in running water until it no longer showed a 
precipitate with BaCl2, this filtrate did not prove toxic to root hairs 
on Tradescantia cuttings placed in it, while controls in bog water 
allowed only a very poor development of root hairs on cuttings of this 
species. 
3. When 500 cc. of filtered bog water was distilled until the residue 
was only 80 cc, the distillate was colorless and was not toxic to root 
hairs on Tradescantia cuttings while the residue was much darker 
in color than bog water and almost entirely inhibited the formation 
of root hairs on these cuttings. 
4. When saturated with (NH4)2S04 and allowed to stand over 
night the above distillate gave no precipitate while the residue gave 
a much heavier precipitate than untreated bog water did. 
5. All samples of bog water tested were acid to litmus and to 
phenolphthalein. 
6. The acidity of the residue mentioned in 3 was greater than 
that of the untreated bog water while the acidity of the distillate 
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