It is a thrilling experience to be engaged in research in a great scientific field at a time when that field is just coming to fruition, when new advances seem to be coming along with ever increasing frequency. Such is the situation in that synthesis of cell morphology and biochemistry which has come to be known as analytical cytology and which is ably dealt with in this volume.
A consideration of the time scale of these developments, contemporary to some of our elder colleagues, demonstrates the dynamic nature of the field.
Still less than half a century since the fundamental discoveries of von Laue and Debye in x-ray diffraction, and only three decades since Herzog began applying diffraction techniques to an analysis of biological structures, we have seen great advances not only in the determination of the macromolecular structure of tissue components but in the elucidation of the detailed intramolecular structure of proteins, carbohydrates, nucleic acids, and other complex substances.
Although electron microscopy is scarcely two decades old, the discoveries which have already been made in biomorphology suffice to indicate that cytology will soon have to be rewritten. The very morphological criteria by which we have now come to recognize cell organelles, such as mitochondria and other cytoplasmic particulates, would have been completely unfamiliar to the expert cytologist of a generation ago. We now identify fibrous proteins by their specific band patterns. Lipid-protein films only a few molecules thick, whose existence has long been postulated by general physiologists, have become old friends to the electron microscopist in the form of double contoured lines seen in thin sections of osmic-fixed tissue.
Highly sensitive optical techniques, applicable to living cells, have become available to the analytical cytologist. Polarization optics has been applied biologically for over a century, but it has been chiefly during the last thirty odd years (especially through application of the Wiener Theory) that advances have been most significant. Phase contrast and interference microscopy, relative newcomers on the scene, have already proven themselves indispensable to the experimental cytologist because of their ability to deal with very small