Preface to Part II
The technique described in Part II is essentially that used by Professor Sander and his co-workers in the Mineralogical and Petrographic Institute of Innsbruck University, the only innovation being the use of an orienting device for more accurate orientation of thin sections and a slightly modified system for marking oriented sections.
When I went to Innsbruck to do research in petrofabric analysis, Professor Sander very kindly placed all the equipment of the Institute at my disposal and helped me in every way possible to learn the technique and to interpret the results obtained. To him my deepest appreciation and thanks are due. His colleagues at the Institute, Dr. Oskar Schmidegg, Dr. E. Felkel, and Dr. Joseph Ladurner, also helped me a great deal and to them thanks are likewise due.
The trip to Innsbruck was made possible by a Sterling Fellowship of the Graduate School of Yale University, and it is a pleasure to acknowledge this invaluable financial assistance.
Professor W. E. Ford, of Yale University, was kind enough to read the completed manuscript, and he made a number of very helpful suggestions, especially concerning the discussion and representation of projections.
Dr. James Gilluly, of the United States Geological Survey, and Dr. James F. Bell made numerous suggestions throughout the manuscript that have added considerably to the smoothness and completeness of the whole.
Discussions with Dr. Fred E. Wright, of the Geophysical Laboratory, were very helpful in shaping the discussion of spherical projection in general and of rotation with the Schmidt net in particular.
Mr. J. Harper Snapp, of the Geophysical Laboratory, made all the photographs for the illustrations, and Mr. Joseph L. Ramisch, also of the Geophysical Laboratory, made the apparatus for orienting thin sections.