"The by-products of the popularity of our volcanoes [have included] * * * science guiding the police, the ranchers to safety, and the public to sight-seeing through ten lava crises. All of these things we have seen grow up during the last twenty-five years" (Jaggar, 1936, p. 4).
Volcanoes affect human communities, and the work of a volcanologist comes almost inevitably to involve questions of public policy and public safety. Jaggar had watched the 1926 Hoopuloa lava flow block a major highway and destroy a village, and he had directed the dropping of aerial bombs on a 1942 lava flow threatening Hilo. He retired (in 1940) before any more major eruptions seriously threatened human life or destroyed property. In his work, Jaggar had dealt principally with those people who held responsible positions in the local community and in major organizations like governments, academia, and publishing. He was gracious and great with ranch managers, but he did not easily exchange banter with cowboys. Islanders respected this volcanologist but did not call him friendly. However, as a pioneering and visionary scientist, Jaggar had few peers. In his 1941 "cornerstone message" (Jaggar, 1941), he predicted: "The laboratories will be disseminated as underground earthquake-instrument cellars, underground temperature measuring wells, electrically controlled measurement stations reporting to a central office, and extended automatic and auto-metric facilities sending wired or wireless messages of underground and overground happenings on Mauna Loa. A volcano observatory must see or measure the whole volcano inside and out with all of science to help. The lesson of a third of a century has been to learn to look underground at the inner earth."
As of the time of writing of this historical summary, the Hawaiian Volcano Observatory has achieved, much that Jaggar foretold. Fifty-one seismic stations radio information to the Observatory, where earthquake epicenters are located by computer within minutes after an event takes place. Electronic tiltmeters also telemeter data to HVO to give an instant report of the ground movement at various points on the active volcanoes. Other geophysical techniques have been added to these. The geochemical program that began with the early collections of volcanic gas at Halemaumau has gone on to calculate a total volcanic-gas budget for Kilauea. The Hawaiian Volcano Observatory and other institutions worldwide have made great strides in understanding how volcanoes work. This knowledge is being translated into forecasts of volcanic behavior that will reduce loss of life and property.
The volcanological community and the Hawaiian Volcano Observatory owe Thomas A. Jaggar, Jr., a debt of thanks for his vision, his dedication, and his persistence during hard times. Through those qualities he contributed much to the present vigor of volcanology. They are the lessons that must be relearned by every generation.
JAGGER AND THURSTON: BACKGROUND
BEGINNINGS OF THE OBSERVATORY
BUILDINGS AND FACILITIES
TECHNOLOGY STATION (1911-1918)
WHITNEY LABORATORY OF SEISMOLOGY (1912-PRESENT)
BUILDING 41 (1940-PRESENT)
BUILDING 131 AT UWEKAHUNA (1927-PRESENT)
NEW BUILDING AT UWEKAHUNA (1985-PRESENT)
PUBLICATIONS AND DOCUMENTS
ACCESS ROUTES AND FACILITIES
THE 1926 ERUPTION
CONTROLLING LAVA FLOWS
THE OHIKI AND OTHER EXPERIMENTS
TRAVEL TIMES OF EARTHQUAKE WAVES
SCALES OF EARTHQUAKE INTENSITY