the natural tannins. It is certainly to be hoped that we may soon see
such works as those of Fischer's and Freudenberg's, recently published,
translated into English. For the guidance of the reader it may be noted
that a short account of the works of these authors may be found in the
_Journal of the Society of Leather Trades' Chemists_, vol. v. (May
issue); in addition to this some of the matter contained in the chapter
on synthesis of tanning matters appeared in the January 1921 issue of
the _Journal of the American Leather Chemists' Association._

In addition to these two sections, the last part of this book deals with
the practical applications of synthetic tannins, and it is hoped that
the tanner will find much valuable information in these pages. The main
outlines of the synthesis of tanning matters should prove of great value
to the chemist engaged in this branch of chemical technology.

The translator takes great pleasure in the acknowledging the valuable
assistance rendered him by Mr. Robin Bruce Croad, A.R.T.C., F.I.C., and
by Mr. Arthur Harvey.

F. G. A. ENNA




CONTENTS

Introduction: Classification of Synthetic Tannins

PART I
SECTION I