1912. 



rUBLIC DOCUMENT — No. 31. 



213 



flooded the bogs, covering the surface with an inch of water. 

 The percohition which followed forced the bog water into the 

 drainage cylinders. The water from nearly every bog on Sep- 

 tember 12 was a dark coffee color, whereas before this date there 

 had been a wide range of tints from dark coffee to light amber. 

 The total solids, and particularly the volatile solids, had now 

 reached a maximum in all but two or three samples, and the 

 amounts were of the same order of magnitude. When sampled 

 for the last time in 1910, on October 19, there was another no- 

 ticeable change in the water. Nearly all the samples were now 

 a greenish black in color, and opaque and inky in appearance. 

 They also were filtered with difficulty. All the samples col- 

 lected during the season had been filtered through dry paper 

 filters to remove suspended matter and sand. The water ran 

 rapidly through the paper and in the earlier collections left 

 little or no stain behind. As the colors deepened the later col- 

 lections stained the filters more and more. The last series 

 deposited a colloidal film on the paper which hindered the pas- 

 sage of the water through the pores and caused the filtration 

 to occupy several hours, in some cases nearly twenty-four hours, 

 while the filtered water had lost its inky appearance and was as 

 a rule a light coffee color. This behavior, together with the 

 appearance of a maximum point in the total solids and volatile 

 solids, points conclusively to a saturated solution with respect 

 to the organic constituents of the peat. 



Table II. — Inorganic Solids in Bog Waters, 1910. 



[Parts in 100,000.] 



