450 BULLETIN OF THE BUSSEY INSTITUTION. 
decolorizing with bone-black, and again evaporating to dryness, 
avery small quantity of water was added, the mixture was heated 
to 60° and set aside in an exsiccator; it dried out to a solid mass 
in which no crystals were visible. Six weeks later, on treating 
the dry residue with alcohol of 75%, a very small portion of it 
dissolved; but most of it dissolved in alcohol of 60%. The 
alcohol solutions, mixed one with the other, showed no indications 
of crystallizing, but dried down to an amorphous mass which was 
taken up with four fifths its weight of water. On adding to this 
solution twice its volume of alcohol of 93%, an apparently gela- 
tinous precipitate began to form and increased on standing. 
This precipitate was found to consist of fine crystals of inorganic 
matter. Moreover, the residue which was left undissolved at the 
time of treating with alcohol of 60% was seen to consist of white 
crystals of inorganic matter. 
For the moment it was a matter of uncertainty whether this 
inorganic matter consisted merely of ash-ingredients proper to the 
wood, or whether it might not have been derived from acids, pro- 
duced in the process of hydrolysis, that were capable of forming 
soluble calcium salts. In the hope of avoiding the inorganic 
substances which had thus far contaminated the ‘* matter insoluble 
in alcohol,” various experiments were now made with carbonic 
acid; and with lead carbonate as the neutralizing agent, instead 
of calcium carbonate or barium hydroxide, and with cotton also 
instead of wood. For the conclusions to be drawn from the 
results of these trials, see page 463. 
The unusually small quantity of sugar (1.07%) obtained in 
the experiment, described on page 449, led to a repetition of it. 
Some 54 grm. of powdered maple root were boiled for 3 hours 
in 1000 c.c. of dilute sulphuric acid of 3.5%, to get rid of xylan 
and starch; the residue was dried in the air and treated with 
70 ¢.c. of strong sulphuric acid of 90% H,SO,, then poured into 
3247 c.c. of boiling water to reduce the acid to a strength of 
3.5% and boiled for 3 hours. The filtrate was neutralized with 
calcium earbonate, and, after the precipitated calcium sulphate 
had been remoyed by filtration, carbonic acid gas was passed into 
the clear liquor which was subsequently boiled. The slight pre- 
cipitate which formed was filtered off, and the liquid was evapo- 
rated to the bulk of 428 c¢.c. It did not need to be decolorized. 
—_ Ee ae eee SS ee ee se eee eee 
