| | FACING PAGE |
|---|
| Thomas A. Jaggar | [Frontis] |
| 1. | Experimental Geology Laboratory, Harvard University, 1900 | [40] |
| 2. | Fountain at edge of lava lake, May 17, 1917 | [41] |
| 3. | Explosion cloud rising from Halemaumau, May 13, 1924 | [56] |
| 4. | Crag in lava lake, January 23, 1918 | [57] |
| 5. | Scientists of Technical Expedition to Aleutians, 1907 | [72] |
| 6. | Captain George Seeley of the Lydia, 1907 | [73] |
| 7. | Volcano House from Observatory, 1913 | [88] |
| 8. | Island in Halemaumau lava lake, 1911 | [88] |
| 9. | Hawaiian Volcano Observatory, 1912 | [89] |
| 10. | Jaggar in seismograph vault beneath Observatory, 1916 | [89] |
| 11. | Lava lake, showing bench, March 30, 1917 | [92] |
| 12. | Halemaumau, showing lava lake and crags, December 8, 1916 | [92] |
| 13. | Jaggar holding pipe for sounding lava lake, 1917 | [93] |
| 14. | River of Alika flow, Mauna Loa, October 6, 1917 | [100] |
| 15. | Lava streaming into a sinkhole in Halemaumau lava lake, July 7, 1917 | [100] |
| 16. | Sakurajima Volcano, Japan, 1914 | [101] |
| 17. | Fountain in lava lake, March 19, 1921 | [101] |
| 18. | Isabel and Tom Jaggar in woods on Kilauea Volcano, 1923 | [120] |
| 19. | Lava lake, fountains, and crags, March 20, 1921 | [121] |
| 20. | Footprints in ash west of Mauna Iki | [121] |
| 21. | The Honukai on Alaska beach, 1928 | [136] |
| 22. | The Ohiki, first amphibian truck, 1928 | [136] |
| 23. | Lava flow entering village of Hoopuloa, 1926 | [137] |
| 24. | Lava flow of 1926 Mauna Loa eruption approaching Hoopuloa | [137] |
| 25. | Jaggar in office of Observatory in “Tin House,” 1937 | [152] |
| 26. | Bomb bursting on lava flow, December 27, 1935 | [153] |
| 27. | Fountain in Halemaumau lava lake, May 23, 1917 | [168] |
| 28. | Rare dome fountain, Kilauea Crater, March 20, 1921 | [169] |
| 29. | Lava stream near rim of Halemaumau, February 9, 1921 | [169] |
| CHARTS |
| Fluctuations of Halemaumau | [113] |
| Diagram of hypothetical globe section | [179] |