SCIENTIFIC PAPERS. 
STUDIES ON THE LIGNIN AND CELLULOSE OF WOOD.* 
BY PERLEY SPAULDING. 
INTRODUCTION. 
In a recent paper Potter f gives the results of some in- 
vestigations upon the cellulose and lignin of the xylem of 
tree stems. By microchemical methods he found that cel- 
lulose occurs as a distinct lining layer in the walls of the 
wood fibers of perfectly healthy trees grown in various 
parts of England. Trees of Quercus, Fagus, Aesculus, 
Salix, Ulmus, Alnus, Betula, and Fraxinus were found 
by him to have cellulose occurring in this manner through 
all parts of the stem; that is, in both heart and sap wood 
at varying distances from the bark. He tested the action 
of boiling water upon the lignin of the cell walls of wood 
by cutting microscopic sections and placing them in water 
in a ‘‘ boiling tube’’ and boiling for about two hours per 
day on consecutive days, the sections remaining in the 
water all of the intervening time. The lignin began to 
leave the walls in four to six hours of boiling in the sec- 
tions of Fraxinus and similar results were obtained with 
other woods, twelve hours being the longest period of boil- 
ing which is definitely mentioned by him. Simple soaking 
of small fragments of wood in told water was then tried 
and it was found that a substance was obtained which had 
* A thesis presented to the Faculty of Washington University, in 
candidacy for the degree of Doctor of Philosophy, April, 1906. — Pub- 
lished by permission of the Secretary of Agriculture. 
+ Potter. Annals of Botany. 183 121-140. (1904). 
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