52 SECTIONAL ADDRESSES. 
microbes into acceptance of molecules which do not harmonise with 
their own enzymic asymmetry. Various apéritifs have been 
administered by skilled chefs de cuisine, but hitherto the little fellows 
have remained obdurate. 
Photosynthesis. 
Beyond a placid acceptance of the more obvious benefits of sunshine, 
the great majority of educated people have no real conception of the 
sun’s contribution to their existence. What proportion of those who 
daily use the metropolitan system of tube-railways, for instance, could 
trace the connection between their progress and the sun? Very moderate 
instruction comprising the elements of chemistry and energy would 
enable most of us to apprehend this modern wonder, contemplation 
of which might help to alleviate the distresses and exasperation of the 
crush-hours. 
For many years past, the problem connected with solar influence 
which has most intrigued the chemist is to unfold the mechanism 
enabling green plants to assimilate nitrogen and carbon. Although 
atmospheric nitrogen has, long been recognised as the ultimate supply 
of that element from which phyto-protoplasm is constructed, modern 
investigation has indicated as necessary a stage involving association 
of combined nitrogen with the soil prior to absorption of nitrogen 
compounds by the roots, with or without bacterial co-operation. _ Con- 
currently, the agency by which green plants assimilate carbon is 
believed to be chlorophyll, operating under solar influence by some 
such mechanism as has been indicated in a preceding section. 
Somewhat revolutionary views on these two points have lately been 
expressed by Benjamin Moore, and require the strictest examination, 
not merely owing to the fundamental importance of an accurate solution 
being reached, but also on account of the stimulating and engaging 
manner in which he presents the problem. Unusual psychological 
features have been introduced. Moore’s ‘ Biochemistry,’ published 
three months ago, will be read attentively by many chemists, but the 
clarity of presentation and the happy sense of conviction which pervade 
its pages must not be allowed to deter independent inquirers from 
confirming or modiiying his conclusions. The book assumes a novel 
biochemical aspect by describing the life-history of a research. The 
first two chapters, written before the experiments were begun, suggest 
the conditions in which the birth of life may have occurred, whilst 
their successors describe experiments which were conducted as a test of 
the speculations and are already receiving critical attention from others 
(e.g., Baly, Heilbron and Barker, Transactions of the Chemical 
Society, 1921, p. 1025). 
It is with these experiments that we are, at the moment, most 
concerned. The earliest were directed towards the synthesis of simple 
organic materials by a transformation of light energy under the influ- 
ence of inorganic colloids, and indicated that formaldehyde is produced 
when :carbon dioxide passes into uranium or ferric hydroxide sols 
exposed to sunlight or the mercury arc lamp. Moore then declares 
