I

1. Ice (see Sea ice)

2. Icebergs:

   1. in the Antarctic, 624, 625

   2. in the Arctic, 667, 668

   3. prediction of drift, 668

   4. transporting sedimentary debris, 953, 1043

3. Indian Ocean:

   1. boundaries, 11

   2. currents, 695–697

   3. oxygen distribution, 697, 698

   4. water masses, 690–695

4. Indicator species, 791–792, 793, 847, 849, 862–863, 865–867

5. Individual population succession, 384

6. Individual time change, 157

7. Inertia, circle of, 437

   1. motion in, 438, 439

8. Inorganic precipitates in sediments, 951, 952

9. Insects, 310

10. Insular shelf, formation of, 24

11. Internal waves, 586

    1. comparison between theory and observations, 597–600

    2. currents associated with, 588–590, 594

    3. effect of Corioli's force, 595, 596

    4. effect on results of dynamic computation, 601, 602

    5. importance to mixing, 601

    6. long, 587

    7. observations, 591–595

    8. short, 586

    9. standing, 600, 601

    10. where density varies continuously, 589–591

12. Interstitial water, 995

13. Intertidal zone, 276

    1. animals of, 276, 840, 844

14. Iodine, 183

15. Ionic activity, 203–205

16. Ionic product, 205

    1. of calcium carbonate, 205–207, 999

17. Irminger Current, 682

18. Irminger Sea, water masses of, 682, 683

19. Iron, 183

    1. as a limiting factor for diatoms, 769

    2. in red clay, 1031, 1032

    3. precipitation of, 952, 1031, 1032

20. Isentropic surfaces, 415, 416

21. Isobaric surfaces, 390, 440

    1. absolute topography, 456, 457

    2. inclination, 410–412, 440

    3. relative topography, 412, 413, 452–455

       1. illustrated, 454, 726

22. Isobaths, 16

23. Isotopes in sea water, 47, 49