Thomas Jaggar examines a 12 ton block ejected from Halemaumau onto ...

Thomas A. Jaggar, Jr., long time director of HVO, was on the mainland at the beginning the 1924 eruption and returned to HVO a few days after the explosions ended. Jaggar's absence left only two HVO staff members to monitor this 2 1/2 week long eruption at Kīlauea. Volunteers from the community pitched in to serve as observers at HVO and helped to preserve an excellent round-the-clock record of the crises from beginning to end.