Xll PREFACE 



chemistry is arising, and from this new field, a histo- and cyto- 

 physiology will develop — and so on in the expanding and exciting 

 quest into the nature of living processes. These new instruments and 

 techniques which carry our vision deep into the living unit, to the 

 molecules and the atoms — they include the beautiful ingenuities 

 which have been refined out of the mountain of past scientific 

 experience, and some which have been newly created for the purpose. 

 It is these instruments and techniques with which we shall be 

 concerned in this book. 



In a discussion on cytological technique, J. R. Baker (1942) of 

 Oxford stated, "It was once remarked to the writer that biochemists 

 like to have their substances in test-tubes. The cytologist wants to 

 have his exactly where they were in life, and to know, as precisely 

 as he can, what they are. When substance and structure are known, 

 the way is clear for the elucidation of the main problem of cytology, 

 which is to discover what a cell does to keep alive and to perform 

 its functions for the body as a whole or for the next generation." It 

 isn't so much "that biochemists like to have their substances in test- 

 tubes" as it is that, until not long ago, biochemists had no means of 

 dealing with substances except in "test-tubes." That biochemists 

 have been fundamentally dissatisfied with this limitation is apparent 

 in their growing efforts to refine their techniques to enable investiga- 

 tions in situ. We can be sure that future campaigns designed to as- 

 sault the present horizons of cytology will follow the strategic lines 

 made possible by the development of equipment and procedures 

 which bring chemical investigations directly to the cell, and the parts 

 of the cell, existing in natural milieu. In the following pages we shall 

 examine the techniques and devices already elaborated for this 

 purpose, and no one with imagination will fail to be impressed and 

 excited by the possibilities engendered. 



Lison's Histochemie Animate, a book dealing mainly with micro- 

 scopic techniques of chemical morphology, was published in Paris 

 in 1936. Many notable advances have occurred since then, and the 

 present volume has been designed to bring together in a compact 

 and readily available form detailed descriptions, not only of the 

 morphologic, but also of the quantitative techniques. Insofar as 

 it has been possible, the material presented has been brought up to 

 date as of January 1, 1947. Pertinent publications which have ap- 

 peared between January 1 and September, 1947, have not been 



