414 BULLETIN OF THE BUSSEY INSTITUTION. 
tained in it there is still left the number 42.68 as the percentage 
of real cellulose in the maple wood. In another trial with the 
May maple there was found 61.44% of cellulose and 7.46% 
of lignic acids, but these determinations were manifestly faulty, 
because some particles of wood, thrown up by the frothing of the 
fused mass, escaped from the action of the melted potash and 
imparted a brown color to the washed cellulose. On oxydizing 
the maple wood with nitric acid of 1.15 sp. gr. there was obtained 
mucic acid enough to represent 1.89% of galactan. 
The outer wood, devoid of bark, of a gray birch tree felled in 
May was found to contain 46.75% of cellulose, 12.81% of.wood- 
gum and 5.44% of lignic acids; while in another trial there were 
found 49.74% of cellulose and 8.83% of lignic acids. From the 
outer wood of a gray birch felled in October there was obtained 
13.54% of wood-gum and 53.23% of cellulose, which contained 
19.63% of its weight of pentosans. Hence the real cellulose in 
the wood was 53.23 — 10.45 = 42.78%. 
Wood of the white pine yielded 55.10% of ** cellulose,” 21.51% 
of lignic acids and 0.96% of wood-gum, as has been said. There 
was obtained also, on oxidizing the pine wood with nitric acid of 
1.15 sp. gr., enough mucic acid to represent 1.38% of galactan. 
C. Cold dilute Alkaline Solutions dissolve very little Wood-Gum 
from the trunks of Coniferous Trees. — The fact, as stated in the 
table in Note A, that only a very small quantity of wood-gum is 
obtained on leaching pine wood with 5% soda lye has been observed 
repeatedly. Yet, in spite of its great theoretical interest and im- 
portance, it appears never to have received the recognition and 
attention which it deserves. It is not easy of explanation in view 
of the other fact noticed by Hoffmeister * that an abundance of 
wood-gum can be obtained from pine and spruce wood by first 
soaking them for 24 hours in cold concentrated hydrochloric acid, 
then washing with water and leaching with 5% soda lye. 
In proof of the small quantity of wood-gum obtainable by the 
direct action of alkaline solutions, Thomsen? says that unlike the 
woods of desiduous trees, which give up to dilute soda lye from 
8 to 26% of wood-gum, fir wood is hardly at all acted upon by 
* Landwirthschaftliche Jahrbiicher. 1888, 17. 259. 
+ Journal fiir praktische Chemie. [N. F,] 19.147. 
