B.—CHEMISTRY. 51 
citric acid, oxalic acid, and carbon dioxide, whilst Wehmer (1918) 
has described the conditions under which citric acid and, principally, 
fumaric acid are produced by Aspergillus fumaricus, a mould also 
requiring oxygen for its purpose. The lactic bacteria are a numerous 
family and resemble those producing acetic acid in their venerable 
record of service to mankind, whilst among the most interesting of the 
parvenus are those responsible for the conversion of starch into butyl 
alcohol and acetone. Although preceded by Schardinger (1905), who 
discovered the ability of B. macerans to produce acetone with acetic 
and formic acids, but does not appear to have pursued the matter 
further, the process associated with the name of A. Fernbach, and the 
various modifications which have been introduced during the past ten 
years are those best known in this country, primarily because of the 
anticipated connection with synthetic rubber, and latterly on account 
of the acetone famine arising from the War. The King’s Lynn factory 
was resuscitated and arrangements had just been completed for adapting 
spirit distilleries to application of the process when, owing to the 
shortage of raw material in 1916, operations were transferred to 
Canada and ultimately attained great success in the factory of British 
Acetones, Toronto. : 
Much illuminating material is to be found in the literature of 1919-20 
dealing with this question in its technological and bacteriological aspects. 
Ingenuity has been displayed in attempting to explain the chemical 
mechanism of the process, the net result of which is to produce roughly 
twice as much butyl alcohol as acetone. The fermentation itself is 
preceded by saccharification of the starch, and in this respect the bacteria 
resemble those moulds which have lately been brought into the technical 
operation of starch-conversion, especially in France. The amyloclastic 
property of certain moulds has been known from very early times, but 
its application to spirit manufacture is of recent growth and underlies 
the amylo-process which substitutes Mucor Boulard for malt in effecting 
saccharification. Further improvement on this procedure is claimed for 
B. mesentericus, which acts with great rapidity on grain which has 
been soaked in dilute alkali; it has the advantage of inferior proteolytic 
effect, thus diminishing the waste of nitrogenous matter in the raw 
material. 
Reviewing all these circumstances we find that, just as the ranks 
of trades-union labour comprise every kind of handicraftsman, the 
practitioners of micro-biochemistry are divisible into producers of 
hydrogen, carbon dioxide, formic acid, acetaldehyde, ethyl alcohol, 
acetic, oxalic, and fumaric acids, acetone, dihydroxyacetone, glycerol, 
pyruvic, lactic, succinic and citric acids, butyl alcohol, butyric acid. 
Exhibiting somewhat greater elasticity in respect of overlapping tasks, 
they nevertheless go on strike if underfed or dissatisfied with their 
conditions; on the other hand, with sufficient nourishment and an 
agreeable temperature, these micro-trades-unionists display the unusual 
merit of working for twenty-four hours a day. One thing, however, 
they have consistently refused to do. Following his comparison of 
natural and synthetic monosaccharides towards different families of 
yeast (1894), Fischer and others have attempted to beguile unsuspecting 
