TRANSACTIONS OF SECTION Be 703 
to act on starch, can readily convert maltose into glucose. It is highly probable, if 
these enzymes were set to work side by side on starch, that the joint hydrolytic 
effect, measured by the amount of starch which disappears in a given time, 
would be greater than it would be if the diastase were working alone. 
Two possible explanations of the increased effect of the presence of yeast on a 
trace of diastase naturally suggest themselves. The first is that the hydrolytic 
process is a reversible one, and is promoted by the rapid removal of the products 
from the sphere of action, the other being that the small amount of acid produced 
during the alcoholic fermentation increases the action of the diastase. Dr. Morris 
has apparently eliminated both these possibilities, in the one case by artificially 
adding maltose to the solutions, and in the other by the addition of a fermented 
malt-extract deprived of its living yeast cells. 
If, however, it is remembered that maltose, when first formed by diastatic 
action, unquestionably differs from the optically stable form which has been in 
solution for some time, and, moreover, that evidence is still wanting as to the 
relative fermentability of these two forms of maltose, the door is not altogether 
closed to the possibilities of the phenomena being after all in some way 
dependent on the prevention of reversal by the rapid removal of the fermentable 
products of change. |? 
MONDAY, SEPTEMBER 18. 
The following Report and Papers were read :— 
1. Report on the Teaching of Natural Science in Elementary Schools. 
See Reports, p. 359. 
2. A Discussion on Atomic Weights was opened by the reading of 
the following communications :— 
Proposed International Committee on Atomic Weights. 
By Professor F. W. CuarKE. 
(Letter to Professor W. A. TILDEN.) 
Washington, D.C., July 19, 1899. 
Dear Sir,—In response to your letter of June 8, I take pleasure in sending you 
a statement of my views relative to the proposed International Committee upon 
Atomic Weights. The suggestions which I have to offer are, however, only my 
own individual opinions, and are not to be regarded as representing any organisa- 
tion, or as based upon any definite programme. Still, they may serve as a basis 
for discussion, and so help to clear a way for progress. 
Every chemist who has studied, with any closeness, the determination of atomic 
weights, has noticed the discordance which exists among the published tables. In 
many text-books and works of reference tables are given which seem to have been 
edited with a pair of scissors and a paste-pot, and which show about as much 
critical acumen in their making up as those useful implements could furnish. Not 
only are obsolete values found persisting, but values are given which are inconsis- 
tent among themselves; and occasionally there is evidence of the most pitiable 
confusion as to the fundamental standards of reference. One table is based upon 
the standard of oxygen as 16; another upon oxygen as 15:88, and still others upon 
the wholly erroneous ratio of 15:96, In one and the same table these several 
1 Owing to want of time the Conference of the two Sections was closed before 
the termination of the Discussion. The remarks in square brackets embody the 
views expressed by the President of Section B at a subsequent date, when Dr. G. H. 
Morris read his Paper on the ‘Combined Action of Diastase and Yeast on Starch- 
granules.’ See p. 710. « 
