REVIEWS. 
British Empire. The book represents a great amount of careful work, especially 
in compiling the references, though some of these show a small proportion of 
quite recent date; for example, on chlorine the most recent is 1907, and only 
twelve out of 52 date after 1900. In nitric acid, 7 of 48 are after 1914. In 
other respects, also, information does not appear always up-to-date. No mention 
is made of a paper published by the United States Government on synthetic 
nitric acid, in which the most reliable figures of costs are given. No mention is 
made of new methods adopted in Germany of preparing ammonium sulphate 
from ammonia and gypsum. 
We think that the fault has been of attempting to cover too many industries 
jn such a small volume, but there is sufficient material to form at least two 
volumes. No less than 63 clearly-drawn figures help to explain the text. 
(2) A large part of this book is occupied with an account of the manufacture 
of intermediate products from which the more important synthetic dyes are 
manufactured. This is as it should be, when we consider that over 80 per cent. 
of the capital outlay in a dyeworks is in plant for the production of inter- 
mediates. ‘The author states that no attempt has been made to enumerate all 
the intermediate compounds and dyes, yet we would like to see some mention 
of isatin, which is of historic importance. Investigations of isatin by Baeyer 
finally led to the elucidation of the constitution of indigo., Also, no mention 
is made of the nitro-benzaldehydes, from the meta compound of which various 
patent blues and fast green are manufactured. 
The various patent processes for the catalytic reduction of nitro-benzene to 
aniline are stated by the author to have not yet:reached tommercial success, 
yet a process. with copper has been worked on a commercial manufacturing scale 
by the German firm of Badische Anilin und Soda-Fabrik, and with nickel Lucius 
and Briining get a yield almost equal to the theoretical. In this and the next 
yolume, we would like to see the German term “ dyestuffs ” abolished, substituting 
“dyes” alone; and the other terms “benzole and toluole” replaced by the more 
modern ‘ benzene and toluene.” 
The literature is extensive and well selected. 
(3) The position of the author, as head of the experimental dye house of 
British Dyes Limited, is suflicient guarantee of the accuracy and_ first-hand 
practical knowledge of the subject. The chemical principles involved, and the 
methods used in the applications of the dyes, are clearly set out in, such a way 
that one may readily understand the subject. This volume, more so than all 
the others, conforms to the Editor’s ideals as stated above. A good historical 
survey, showing the gradual growth of the industry and the present influences 
and tendencies, are clearly stated. The subjects covered include the basic and 
acid dyes, the alizarine and other mordant dyes, the direct cotton dyes, the azo 
and sulphur dyes, and indigo and other vat dyes. The enormous extension in 
the dyeing of mixed fabrics of silk, wool, cotton, and artificial silk, must be 
credited to the direct cotton dyes, whilst the increasing success of present-day 
garment dyeing is directly attributable to the same colours. On cotton, we read 
that the anthracine vat dyes are fast, that the azo dyes rub and sub-lime off the 
fibre, and that indigo on wool is the standard of fastness for blues on wool, 
and that there are no bright scarlet, crimson, or violet dyes in the sulphur group. 
The demand .for cheap new clothes often, instead of long-lasting expensive 
ones, has led to great advances in the dyeing of garments of mixed fabrics. 
An unusually difficult subject has been treated in a most readable and 
interesting manner, without introducing very much theory. The book should 
be in the hands of every person in any way connected with dyeing, and, moreover, 
many recipes can be found of value to other traders, such as inkmakers, confec- 
tioners, tanners, and furriers. The whole section on the dyeing of union materials 
would form a useful handbook for all dyers and cleaners. 
(4) This volume also conforms to the high ideals of the Editor. Mach section 
is complete in itself, and the various parts might readily form separate booklets. 
The subjects covered include fertilizers, soils, crops, and the production of meat. 
The extensive bibliography throughout is very good, most of the references being 
quite up-to-date. The law of diminishing returns, mentioned on page 83, taken 
from the Rothamsted results, are equally applicable to Australia in the case of 
the use of superphosphate as a wheat manure. The use of mixed fertilizers, as 
given in section 4, does not apply so much to Australia as England. | Natural 
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