Bouwers, A. 1946 Achievements in Optics pp. 135, being Vol. 1 in Monographs on the Progress of Research in Holland during the War, R. Houwink and J. A. A. Ketelaar, editors. Amsterdam, Elsevier.
This compact volume, the first in a remarkable series intended "as a token of the undaunted spirit of the Netherlands" was begun under the nose of the invader. Its interest for the practicing microscopist is at least twofold, for its consideration of some fundamental problems of geometrical and physical optics which may have long-range effects on optical design and for the introduction of new instruments. Of the latter, reprints in English of Bouwers Nederiandsche Natuurkundige Vereeniging paper of October 1943 on his new mirror microscopes and of Zernike's now classical paper "Phase contrast, a new method for the for the microscopic observation of transparent objects" (Physica, 9: 686, 1942), place this little book on the must list for science libraries and for senior students of microscopy.
Houwink, A. L., J. B. LePoole and W. A. LeRutte {editorial committee) 1950 Proceedings of the Conference on Electron Microscopy Delft 4- 8 July 1949, pp. 188, Delft, Hoogland.
It is fitting that Delft, the city hospitable to Leeuwenhoek's pioneering observations with the light microscope, should be three centuries later the scene of a seminal conference on electron microscopy, drawing a group of more than 200 investigators (from most parts of the non-Sovietized world) presenting 46 papers. The studies range from discussions of present instruments, methods and accomplishments through considerations of the nature of suitable electron sources, lens systems and their aberrations, and resolving power to presagement of developments of coming years. Particularly intriguing are attempts to realize a phase contrast electron microscope (Agar, Revell and Scott of Manchester) and to develop electron diffraction microscopy to realize a resolving power beyond 10 Angstroms (D. Gabor of London).
The editors apologize for the stringent cutting of papers and for the quality of reproduction of photographs in the economy of publication. Whatever has been lost in the cutting, the remainder constitutes a revealing, valuable review of the current state of electron microscopy --- certainly a highly needed supplement to G. H. Scott's section on the preparation of tissues for electron microscopy in the new edition of Mc- Clung's Handbook of Microscopical Technique. If the editors' disparagement of the reproduction of figures is at all warranted, the originals must in many cases be magnificent.
J. L. Mohr
Department of Zoology University of
Southern California