This book is a survey of the historical development of chemistry,
from its origins to the present time. The aim has been to provide a
deeper and fuller understanding of the ideas and methods of the
science by integrating the evolution of chemistry with the onmarch
of history in general. A review of man's first recorded interest in
the chemical transformation of materials that lay ready to hand is
followed by a description of the ways by which chemical beliefs de-
veloped into ideas, how ideas developed into theories, and how prac-
tices evolved into experimental methods of research. The searching
and experimentation of the past are so described that they may well
provide both stimulation and special examples for solving present-day
problems.

Investigators through the ages have contributed to our present-day
knowledge of the nature of substances, affinity, and chemical reactions.
Throughout the volume, so far as possible, the story has been told by
letting old records relate what actually took place. This has been
done by making a careful and objective selection of pertinent material
in early books and periodicals that are not readily accessible, and
from the professional papers, lectures, and letters of great chemists.
In this way, the chronicle constructs a solid basis for interpreting the
manifold connections between imagination and necessity, between
theory and experiment.

The reader of these pages will soon discern that the development
of chemistry has from earliest times gone hand in hand with progress
in other sciences and philosophies, especially medicine, mineralogy,
botany, zoology, physics, and engineering. For this reason it is
hoped that this volume will be found useful not only by students of
chemistry and by professional workers in the field but also by all who
have an abiding interest in the advancement of human knowledge.

EDUARD FARBER

Washington, D. C.

August, 1952

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