314 Prof. H. E. Armstrong and Dr. W. H. Glover. [Apr. 2, 
There can be little doubt that considerations of the order here pictured are 
more or less applicable to the explanation of differences such as those under 
discussion and that it may be possible eventually, proceeding on these lines, 
to discriminate between alternative formule applicable to compounds such as 
glucose and galactose. It is from this point of view that the study of 
hydrolytic changes is of supreme importance. 
Enzymes probably act much in the same way as acid hydrolysts; the 
attachment of the enzyme, however, appears to be more general and 
thorough, so to speak, than that of the acid hydrolyst and presumably 
extends over a large part of the molecule (compare III and X, B, vol. 79, 
p. 361). But in both cases the attack is directed, it may be supposed, from 
the oxygen atom in the pentaphane ring adjoining the group which undergoes 
hydrolysis. 
In the hope of obtaining further information bearing on this refined 
problem, the behaviour of raffinose towards acids and enzymes has been 
studied in comparison with that of cane-sugar, raffinose being a triose formed 
of cane-sugar weighted by the attachment of a molecule of galactose. 
Raffinose is a reserve material which accompanies cane-sugar in the sugar 
beet, in cotton seed, in barley and in wheat, for example. It can either 
be resolved into galactose and cane-sugar by a special enzyme or it can be 
resolved into fructose and a biose isomeric with cane-sugar—melibiose—by 
the action of invertase, the enzyme which resolves cane-sugar into glucose 
and fructose. 
Hydrolysis of Cane-sugar and Raffinose with the aid of Acids. 
Raffinose is easily hydrolysed with the aid of acids at ordinary tempera- 
tures, the products being fructose and melibiose, the latter, like maltose and 
milk-sugar, undergoing change only at higher temperatures. 
The experiments with acids were carried out at 25° C. in the manner 
described by Caldwell (A, vol. 78, p. 285), with an improved apparatus 
an account of which will be given at an early date by Messrs. Caldwell and 
Whymper. Except where stated otherwise, the polariscope readings were 
taken with the aid of a spectroscopic eyepiece, using a mercury lamp as the 
luminous source, the light being of the refrangibility of the dominant line in 
the green. As raffinose is less soluble than cane-sugar, solutions of quarter 
molecular strength were used. A complete record of two experiments is 
given on the left-hand side of Table I. The columns on the right contain 
the values of the velocity constant deduced by means of the formula 
a 
Ge Pere cae 
Ot oe 
K = — 
t 
