186 
NATURE 
[NovEMBER 9, 1916 
to the country of many brilliant and promising 
members of the younger research workers, who 
cannot be quickly replaced. 
The glossary contains a large amount of in- 
teresting information. Some sections are con- 
tributed by experts, but we think that in many 
cases British work is unduly depreciated or neg- 
lected. In the section on “Telephones ” the name 
of David E. Hughes, the inventor of the micro- 
phone, is not even mentioned, nor that of Oliver 
Heaviside, whose mathematical work led to the 
invention of the loaded cable. 
: The section on “ Wireless Telegraphy ’’ is very 
inadequate as a sketch of the subject.. The writer 
seems to think that the coherer is still used as a 
receiver, whereas it has long since been aban- 
doned. Two out of three of the actually used 
modern detectors are British inventions. Mar- 
coni’s work, all carried. out in England, is not 
sufficiently appreciated. 
British invention in connection with submarine 
cable work, almost entirely a British industry, is 
ignored. The initiative quality of British 
scientific research is not sufficiently acknowledged. 
Nevertheless there remains sufficient to justify the 
main contentions of the book. We have all to 
turn over a new leaf, to reform educational 
methods, to work much harder, play much less, 
and bring the scientific method to bear on every- 
thing, or else the eclipse the authors foresee most 
certainly awaits us in the post-war struggle for 
commercial empire. J. A. FLeminc. 
” 
VINEGAR. 
Vinegar: its Manufacture and Examination. By 
C. Ainsworth Mitchell. Pp. xvi+201. 
(London: Charles Griffin and Co., Ltd., 1916.) 
Price 8s. 6d. net. 
HIS book seeks to fill an admitted void in the 
technology of an important fermentation in- 
dustry. Works on the subject are to be met with 
in French and German literature, but their bear- 
ing on English procedure is only indirect, since 
the methods and conditions of acetification. in 
this country are fundamentally different from 
those prevailing on the Continent. 
Strictly speaking, the manufacture of vinegar— 
that is, the commercial preparation of a dilute 
acid from wine, capable of being used as a con- 
diment or preservative, is not, and never has been, 
a British industry, since wine is not one of our 
native products. A similar, but by no: means 
identical substance, was made in this country, 
even in very early times, by the souring of beer, 
and was known as ‘“‘alegar’’—a term practically 
now obsolete, or only to be met with in certain 
local glossaries. Formerly a clear distinction 
was drawn between the Continental and the native 
commodity. Thus Boorde’s “Dyetary” (1542) 
speaks of “Soure and Tarte Thynges as Venegre 
and Aleger,” and for many years the term vinegar 
was restricted to the imported variety derived 
from wine: So little was known in this country 
concerning the manufacture of this special article 
NO. 2454, VOL. 98] 
that the Royal Society, in one of the early volumes 
of its Transactions, published “The Way of 
making Vinegar in France: Communicated to the 
Publisher by an Ingenious Physician of that 
Nation, living at a Place where much of it is 
Made.” i 
With us the manufacture of vinegar—using that 
term in its generic sense—still bears the impress 
of how it originated in this country—that is, from* 
beer. Formerly the only useful way of disposing 
of sour beer, whether in the brewery or the house-— 
hold, was to turn it into vinegar. But as the. 
demand for vinegar increased some more regular: 
supply than “sick” or badly brewed beer was. 
needed, and the manufacture was gradually placed. 
upon a systematic and independent basis. Still 
this connection between the brewer and the 
vinegar maker long persisted. _ The fiscal authori-, 
ties at least swept them into a common net—the_ 
fermented malt-product, no matter whether it was 
sweet or sour, coming within the purview of the 
gauger—although ‘‘ Vinegar-Beer,” as a Revenue 
Act of Charles II. termed the product, was let off. 
with a lighter impost. “ Vinegar-yards,” as dis- 
tinguished from the “common _ brew-houses,”” 
seem to have been first established in this country; 
about the middle of the seventeenth century. Py 
In the book under review Mr. Ainsworth 
Mitchell, who acts as chemist to the well-known 
firm of Messrs. Beaufoy and Co., one of the oldest 
and largest vinegar manufacturers in this country, 
has brought together a body of valuable informa- _ 
tion concerning the history of vinegar in general, 
its different varieties, and various modes of pro-. 
duction, with special reference to English pro- 
cedure; and this information he has presented in 
an interesting and eminently readable form. In 
his historical retrospect he begins his account at, 
the period when vinegar received a certain amount 
of scientific attention from the early alchemists, 
and their immediate followers, the iatro-chemists, 
who speculated upon its nature and physiological, 
action. It is interesting to note that certain of 
their crude theories still persist in old wives” 
fables, and in the practice of quacks. The author 
touches lightly upon the early theories of acetifica- 
tion, but of course he deals with the suppositions 
of Liebig and the far sounder views of Pasteur, 
Nageli’s mechanical theory, and the more modern | 
Enzymic theories. This is followed by a descrip- 
tion of the acetic bacteria, their various species, 
zoogleal condition, and involution forms, and 
the effect of light and oxygen upon them. These 
chapters are fully illustrated, showing the morpho- 
logical changes of the bacteria due to age, and 
the character of the medium. They do not pre- 
tend to be exhaustive, as they are intended rather 
for the general reader than for the specialist, but 
so far as it goes the account is sound, and no 
important point is omitted. The chemical 
reactions in acetification are next dealt with, in- 
cluding the production of aldehyde, acetal, and 
the various esters which confer upon the different 
vinegars their characteristic aroma and other 
peculiarities. Next follows a description of acetic 
acid, its chemical and physical properties, and its 
