78 BULLETIN OF THE BUSSEY INSTITUTION. 
hot either of these liquids discharged the color immediately and com- 
pletely without forming a colored solution. When a bit of the colored 
residue was heated upon platinum foil the color became somewhat 
fainter, apparently by dissemination through the mass of material, 
rather than from any destruction or alteration. By fusion with 
nitrate of potash and carbonate of soda upon platinum foil a faint 
reaction for manganese was obtained. It seemed probable, though 
not certain, that the green color was due to manganese, —perhaps to 
the presence of an insoluble manganate. No phosphoric acid could 
be detected in the concentrated aqueous solution by means of molyb- 
date of ammonia. 
It is my intention to have the so-called absorptive or fixing power of 
coal-ashes investigated with care, —i.e. their power to absorb from 
solutions and to hold potash, ammonia, and similar bases. The few 
experiments, recorded below, which have already been made in that 
direction need to be supplemented by others before any very definite 
conclusions can be drawn from them. The method of experimenting 
was essentially that described by Peters.* 100 grammes of the sifted 
ashes were placed in a glass-stoppered bottle with 250 ¢. c. of the 
saline solution to be tested. The mixture was shaken at definite 
times, and, after twenty-four hours had elapsed, a portion of the solu- 
tion was run through a dry filter that had been previously thoroughly 
leached, and definite fractions of the filtrate were taken for analysis. 
The saline matters employed were all prepared from pure chemicals 
in the first place and recrystallized afterwards. . 
I. For the trial with sulphate of potash, 2.18 grammes of that salt 
were dissolved in water to the volume of 250 cc. After twenty- 
four hours’ contact with 100 grammes of ashes, there were found in 
the solution 
0.1090 gramme of lime, . 
0.7910 a ‘¢ potash. 
No attempt to estimate the amounts of sodium or of lithium was 
made. There was no magnesia, nor was any matter precipitable by 
ammonia found in this liquid or in any of those subsequently tested. 
Since the original solution of sulphate of potash contained 1.1790 
grammes of potash, it appears that in this trial 0.3888 gramme of pot- 
ash was absorbed and fixed by the 100 grammes of ashes. 
* Die landwirthschaftlichen Versuchs-Stationen, 2, 29. 
