1. Rabi, I. I., 1
2. radio communication, 1
3. radio waves, 1, 2, 3, 4 n. 11
4. radioactive dating, 1
5. radioactivity, 1, 2 n. 5
6. radium, 1
7. Raglan, Fitzroy Somerset, 4th Baron, 1
8. rain, 1, 2, 3
9. Ramón y Cajal, Santiago, 1
10. Raskin, Jef, 1 n. 1
11. Raspall, François-Vincent, 1
12. receptors, see neurons
13. red dwarfs, 1
14. red giants, 1, 2 n. 23
15. Red Queen Hypothesis, 1
16. red shift: cosmological, 1;
    1. gravitational, 1
17. reduction, 1 n. 4
18. relativistic aberration (or beaming), 1 n. 1
19. relativity, 1, 2;
    1. covariance, 1 n. 9;
    2. general theory of, 1, 2, 3, 4, 5, 6 n. 6 infra, 7 n. 3, 8 n. 9, 9 n. 13;
    3. special theory of, 1, 2, 3, 4, 5, 6, 7, 8 n. 9
20. Resnikoff, Howard, 1
21. respiration, 1
22. ribosomes, 1, 2
23. rice, 1
24. RNA (ribonucleic acid), 1, 2;
    1. information storage, 1 n. 4;
    2. and proteins, 1, 2 n. 4;
    3. replication, 1 n. 4
25. rocket, 1, 2, 3;
    1. propulsion, 1, 2, 3, 4 n. 2
26. rocks, 1, 2, 3, 4, 5;
    1. iron-rich, 1;
    2. magnetism, 1;
    3. radioactive, 1;
    4. sedimentary, 1, 2 n. 2;
    5. volcanic, 1
27. Rohrer, Heinrich, 1 n. 3
28. Royal Belgian Institute of Natural Sciences, 1 n. 6
29. Royal Society, London, 1
30. Rumsfeld, Donald, 1
31. Russia, 1 n. 1
32. Rutherford, Adam, 1
33. Rutherford, Ernest, 1
34. Ryan, Robert T., 1