Introduction 504
1. Primary Cosmic Rays Near the Earth 505
a) Chemical Composition 505
b) Energy Spectrum 506
2. Radio-Astronomical Data 509
a) Magnetic Bremsstrahlung (Synchrotron Radiation) 509
b) Certain Results of Observations and their Interpretation (Structure of the Galaxy, Discrete Sources) 510
3. Lifetime of Cosmic Rays and the Character of their Motion in the Galaxy and in the Metagalaxy 515
a) Nuclear Lifetime of Cosmic Rays 515
b) The Role of Cosmic Rays Produced at an Earlier Stage of Evolution of the Galaxy 517
c) Character of Motion and Escape of Cosmic Rays from the Galaxy 518
d) Cosmic Rays of Metagalactic Origin 520
4. Sources of Cosmic Rays. Mechanism of Acceleration and Chemical Composition of Cosmic Rays 524
a) Sources of Cosmic Rays 524
b) Mechanisms of Acceleration and Energy Spectrum of Cosmic Rays. Possibility of Preferred Acceleration of Heavy Nuclei 526
c) Transformation of Chemical Composition of Cosmic Rays in the Interstellar Medium. 531
d) Discussion of the Chemical Composition of Cosmic Rays 533
Concluding Remarks 536
Literature 538