BULLETIN OF THE BUSSEY INSTITUTION. 467 
misplacing by the printer of a character representing a bent 
arrow in such wise that the arrow was made ‘to point to the left 
instead of to the right, —it was there made to appear that the 
rotation of the wood-dextrin is to the left, though a careful read- 
ing of the context shows clearly enough that Béchamp meant to 
assert that the rotation of this substance is really towards the 
right hand. It is to be noted, moreover, that Béchamp was one 
of the last men in the world to speak of a left-handed deatrin ; 
for he worked at a time when the word ‘‘ dextrin”? was new, and 
he had always in mind the derivation and the real meaning of the 
word. In his memoirs he refers repeatedly to the fact that the 
substance named ‘* dextrin”’ by Biot was really not the substance 
known as ‘‘ dextrin” in commerce, but an impure soluble starch 
(now often called amylo-dextrin). The misprint was copied un- 
wittingly into several standard works,* where it has remained an 
effective stumbling-block to perturb the unwary. 
VIII. The difficulty of studying the products of the hydro- 
lysis of cellulose is manifestly increased by the fact that not only 
do ‘* dextrins”’ result from the splitting up of the copulated com- 
pounds formed by the union of strong sulphuric acid with carbo- 
hydrates, but that phenomena of reversion of dextrose to dextrin 
may occur in the process of hydrolyzing with diluted acids. 
What connection there may be between the dextrins thus formed 
by reversion of dextrose and those obtained by the breaking 
down of cellulose-sulphuric acid, appears to be still an open 
question. It has been reported merely that the reducing and 
rotatory powers of the former are lower than those of the latter. 
I am greatly indebted to my assistant, Mr. Winfred W. Braman, 
for his careful attention to the performance of many tedious and 
discouraging details of manipulation, which have had to be worked 
out in the course of this investigation. 
* See, for example, the Cavendish Society’s edition of L. Gmelin’s Hand- 
book, 15. 188; and Watt’s Dictionary of Chemistry. 1866, 2. 313, 314. 
So, too, in the 1862 (German) edition of Gmelin’s Handbuch. 7. 633, where 
the error was evidently copied from the English edition. 
It is noteworthy that the editor of the Journal fiir praktische Chemie on 
translating, for publication in his journal (1861, 82. 121), Béchamp’s article 
at the time of its appearance, corrected the misprint, though without com- 
ment. Hence the error does not appear in those German treatises which 
have taken their information from the Journal fiir praktische Chemie. 
