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21 JANUARY 1955 1A

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CONTENTSElementary Particles

The Magnetic Moinent of the Electron P. KUSCH, Columbia UniversityCosmic Ray Experiments at High Altitudes EDWARD P. NEY, University of MinnesotaDevelopments in Cosmic Radiation, 1945-1950 J. C. STREET, Harvard University

Physics of the Solid StateThe New Electronics KARL LARK-HOROVITZ, Purdue UniversityFlow of Electrons and Holes in Semiconductors J. BARDEEN, University of IllinoisBarium Titanate Ferroelectrics A. VON HIPPEL, M. I. T.

Chemical PhysicsThe Structure of Polymers PETER J. W. DEBYE, Cornell UniversityImplications of the Chemical Kinetics of Some RUFUS LUMRY and HENRY EYRING,

Biological Systems University of Utah

BiophysicsSome Physical and Chemical Properties of Axon FRANK BRINK, JR.

Related to Conduction of Nerve Impu Johns Hopkins UniversityBioluminescence and the Theory of Reaction FRANK H. JOHNSON,

Rate Control in livig System Princeton University

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SCIENCE, VOL. 121