The understanding of artists' techniques gives rise to a complex of questions which have
occupied me for many years. In conjunction with a number of distinguished artists and
technicians, I have also made numerous practical experiments connected with the develop-
ment, particular resources, expressive power, and limitations of different techniques. The
theme of the present book emerged in the course of these experiments; therefore, this is
not as first may appear, a purely theoretical work, but is based on practical foundations
laid over a long period.

Some of the material which I have used in my previous works--which have not been
available in the English language--has been added as an appendix to this book, enhancing
its value and rounding off the subject.

I should like to express my thanks to the artists, Willi Baumeister, Georg Muche and
Oskar Schlemmer; to the museum directors and experts--and especially to Professor
Ferdinand Lammeyer--who gave me their very kind co-operation and supplied me with
specialist information, without which it would have been impossible to write this book;
also to my scientific assistant, Dr Beatrix v. Ragué, who gave me her support throughout
its preparation.

Wuppertal, Spring, 1958 Kurt Herberts

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