BULLETIN OF THE BUSSEY INSTITUTION. 391 
were analyzed by Dietrich * in Stoeckhardt’s laboratory. In 1853 the 
naturalist Seeman + wrote as follows : — 
‘«The practice of mixing alder bark (Alnus incana) with dough is 
not now in use at Petropaulowski, but is still prevalent among the 
natives in the interior.” 
As regards the trustworthiness of the figures for starch (and 
sugar) above given, it is manifest that by means of malt, as ap- 
pled in the manner stated, it is practicable to obtain a fairly accu- 
rate estimation of the amount of starch naturally contained in 
a wood, ‘That is to say, the starch may be determined with ade- 
quate accuracy, after any sugar which may be contained in the 
wood has been washed out, and the amount of it estimated. Due 
attention should be paid to the consideration of this point, be- 
cause of the fact that the much higher figures as to the quantity 
of starch in woods which have occasionally been published, un- 
doubtedly depend in some cases upon the employment of improper 
methods of analysis. As will appear directly, it is quite imprac- 
ticable to estimate the starch in wood by means of methods which 
depend upon the conversion of starch to sugar by the action of 
hot dilute acids. Thus the method of estimating starch devised 
by Sachsse, which as Winton { has shown, is well fitted for use 
upon starch-bearing grains and tubers, is not in the least appli- 
cable for determining the starch in woods, because there is pro- 
duced by the action of the acid upon the wood a quantity of 
pentoses, which reduce the copper salt as readily as does the dex- 
trose which is formed simultaneously with them by the action of 
the acid upon starch. | 
Results obtained by Subjecting Wood to the Action of Hot Dilute 
Hydrochloric Acid of about 2.5%, as in Sachsse’s § Process for 
Estimating Starch. 
Three grm. portions of the powdered woods were treated with 
a mixture of 200 cc. of water and 20 cc. of hydrochloric acid of 
sp. gr. 1.125, and heated during three hours in a boiling water- 
bath, and the sugar thus formed was determined by means of 
copper, according to Allihn.|| It is manifest from the results 
* Der Chemische Ackersmann. 1855, 1. 105. 
+ Voyage of the Herald. 2. 6. 
t Report of the Connecticut Agricultural Experiment Station. 1887, p. 128. 
§ Chem. Centralblatt. 1877, 8. 732. See also Wiley’s Agricultural 
Analysis. 3. 203, 205. 
|| See Wiley’s Agricultural Analysis. 3. 155. 
