Page 2 - A TEXTBOOK OF ORGANIC CHEMISTRY

PREFACE TO 1941 EDITION

It is thirty-three years since the first Revised English
Edition of Bernthsen's Tertbook of Organic Chemistry ,was
published, and during these years this branch of chemistry
has made enormous advances. The three most marked direc-
tions of this advance have been (l) in the borderland between
Physical and Organic Chemistry; (2) in the growth of Bio-
chemistry; (3) in the development of the industrial and
manufacturing side.
The modern conception of atomic structure has led to new
views on the mechanism of many organic reactions as exem-
plified in aromatic substitution, tautomerism and co-ordinated
compounds. It has also entailed the development of the study
of such physical properties as dipole moments, lengths of
links and X-ray structure.
The study of Biochemistry has entailed a closer study of
fermentations, enzyme actions, food metabolism and the
functions of vitamins and hormones; also detailed studies
of products from the animal and vegetable kingdoms, such
as colouring matters, steroids, alkaloids, &o.
Fifty years ago the synthetic dye industry was the chief
manufacture based on organic chemistry, This industry has
made great strides within the past thirty years, especially as
regards azo dyestuffs and vat dyestuffs, but in addition new
industries have been developed dealing with synthetic fibres
such as rayon, plastics, rubbers, and synthetic drugs, including
arsenicals, not to mention oil hardening and fermentation
industries such as the manufacture of butyl alcohol and
glycerol. The catalytic use of finely divided metals, metallic
oxides and salts has also been utilized in the manufacture of
numerous compounds.
Attention must also be drawn to the developments in
Stereochemistry.
References to all these advances have been incorporated in
this Edition, which attempts to give a review of the various
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