It gives me particular pleasure to write the foreword to this book; this is largely due to the fact that I have devoted a substantial part of my life to the improve ment of the methods used in ophthalmic research. Rarely has one of my students taken the opportunity of dealing systematically with the possibilities of these methods. Dr. Eisner is, however, one of these exceptions. First, he has substantially improved the indentation contact glass; secondly, he has, with untiring enthusiasm, ...