S-'EBR1,14 CEC-DETSMNS1

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The Bausch & Lomb Spherical Microscope Lamp pro-vides a flexible, efficient source of illumination forvarious types of microscopy. It is supplied with groundglass and blue glass filters, or with Corning Daylite fil-ter . . . with double-plano-convex or Aspheric con-densers, the latter for the most critical work . . . andwith or without iris diaphragm. Bausch.& Lomb Op-tical Co., Rochester 2, N. Y.

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12 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2646

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ELECTRON OPTICS- ~AND THE

ELECTRON. MICROSCOPEBy V. K. Zworykin, G. A. Morton, E.Ramberg, J. Hillier, A. W. Vance; allRCA Laboratories, Princeton, N. J.

G.at

This comprehensive book covers the electronmicroscope in all its phases. The material for thebook was chosen to fulfill a twofold purpose. Thefirst is to aid the present or prospective electronmicroscopist in understanding his instrument andin using it to greatest advantage; the second, topresent systematically the practical and theoreti-cal knowledge which must form the basis for furtherprogress in electron microscope design.

To this end the book has been divided into twoparts. The first part contains descriptions of vari-ous types of electron microscopes together with a

non-mathematical discussion of the electron opticaltheories on which the electron microscope is basedand the practical information necessary for its ef-fective operation. The second part presents a sur-

vey of theoretical electron optics and employsmathematics as liberally as a methodical develop-ment of the subject matter warrants. This treat-ment is intended to supplement the practical in-formation of the first part and may serve as a guidein electron optical design.

JOHN WILEY & SONS, Inc., 440-4th Ave., New York 16, N. Y.

CONTENTSPart I-PRACTICAL ELECTRONOPTICS AND ELECTRON MI-CROSCOPY * Electron Optics *Applications of Electron Optics *Electron Microscopes * ElectronOptics of High Magnification *The Magnetic Electron Microscope* Aberrations and Tolerances inthe Electron Microscope * ElectronMicroscope Power Supplies * Ma-nipulation of the Electron Micro-scope * The Electron Microscopeas a Research Instrument.

Part II-THEORETICAL BASISOF ELECTRON OPTICS ANDTHE ELECTRON MICROSCOPE* Theoretical Basis of ElectronOptics 0 Determination of Poten-tial Distribution * Electron Tra-jectory Tracing * Gaussian Diop-trics of Electrostatic Lenses *Magnetic Fields * Electron Motionin Magnetic Fields and MagneticLenses * Aberrations of ElectronLenses * Magnitude and Correctionof Electron Lens Defects * High-Voltage Electron Optics-Ion Optics* Image Formation in the ElectronMicroscope.

APPENDIX

12 SCIENCE-ADVERTISEMENTS VoL. 102, No. 2646

7A4

SCIENCE-ADVERTISEMENTS

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ILATE

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