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June 1, 2006

A weekly feature provided by scientists at the Hawaiian Volcano Observatory.

He's back! Thomas Jaggar returns to the Whitney Vault

Carefully retouched sepia without Jaggar Isabel sepia
Left: Carefully-retouched Jaggar sepia. Right: Isabel sepia.

Thomas Jaggar, the scientist who founded the Hawaiian Volcano Observatory (HVO), is again enthralling visitors to Hawai`i Volcanoes National Park with his passion for science and his many stories about volcanoes. Despite his death in 1953, he seems full of the spark and determination with which he founded HVO in 1912 and advocated formation of the National Park in 1916.

In his earlier life, Jaggar certainly had vision about the importance of understanding volcanoes in order to minimize their destruction. In addition to founding HVO, he also started two other volcano observatories. The second was established at Mount Lassen in northern California after an eruption there in 1914-15. In 1929, Jaggar started two seismic stations in Aleutian Islands, Alaska.

The Lassen and Aleutian observatory operations were headquartered at the Hawaiian Volcano Observatory at Kilauea Volcano. In 1926, Jaggar was appointed the head of the Volcanology Section of the U.S. Geological Survey in recognition of his efforts.

Jaggar's knowledge was not limited to U.S. volcanoes. He traveled extensively and was frequently called upon to visit volcanoes around the world. Many of his publications tried to relate processes he observed at more dangerous volcanoes to those he observed at Kilauea Volcano.

He was just as determined to get his findings out to the public as he was in solving the scientific puzzle that volcanic eruptions pose. He started as director of HVO on January 17, 1912 and put out his first weekly bulletin the next day. The bulletins were sent via wireless to Honolulu to his primary supporter in Hawai`i - Lorrin Thurston and would appear about four days later in the Advertiser, the Hawai`i newspaper that Thurston founded in 1900.

He firmly believed that "by clear and forceful speech science may educate" "Keep and publish careful records, invite the whole world to cooperate, and interest the business man." Perhaps his bulletins and Volcano Letters, published through his retirement in 1940, were really the first "Volcano Watch" columns. In any case, he was a prodigious writer publishing several hundred papers and a few books, delivering many public speeches, in addition to posting his persistent volcano updates.

Present day visitors also meet Miss Isabel Maydwell, Jaggar's coworker, who became his wife. In 1945, Jaggar dedicated one of his many publications to her with these words: "To helpmeet and campmate, ISABEL JAGGAR, / Whose horse crushed her against a tree . . . /, Whose gloves fell into a red hot crack and burned up . . . /, Who slept in a lava tunnel beside the immortal remains of a desiccated billy goat . . . /, And loved it all." That tells you a lot about both of them.

Visitors can chat with this lively pair in their old haunt, the Whitney Laboratory of Seismology. The vault, located on the north rim of Kilauea caldera, is the site upon which Jaggar first installed several instruments capable of detecting earthquakes. Observatory staff had offices above the vault until they were razed to make way for the current Volcano House in 1941. The vault is on the National Register of Historic Places.

These figures from the past are brought skillfully to life by local actors Peter Charlot and Sandra MacLees. Peter knows Thomas Jaggar well after having resurrected him once before in a play he wrote titled "The Vision of a Scientific Missionary." The work was commissioned by the Volcano Art Center in celebration of the 75th anniversary of the founding of the Hawaiian Volcano Observatory and was successfully staged on several islands.

At the time, Peter was convinced that "Jaggar wrote the play using him," according to an interview with Honolulu Star Bulletin correspondent Rod Thompson. "He was not the kind of man who let a little thing like his own demise stop him," Charlot said.

Apparently, Thomas Jaggar was dissatisfied with just writing through Peter and chose to periodically inhabit his whole being. The interested visitor need only meet Isabel (played by Sandra) at the Park Visitor's Center each Friday morning at 9:30, 10:30, and 11:30 a.m. to begin the walk back into history to meet Dr. Jaggar.

Activity update

This past week, activity levels at the summit of Kilauea Volcano have remained at background levels. The number of earthquakes located in the summit area is low (usually less than 10 per day). Widening of the summit caldera, indicating inflation, appears to have resumed after pausing earlier in April.

Eruptive activity at Pu`u `O`o continues. On clear nights, glow is visible from several vents within the crater. Lava continues to flow through the PKK lava tube from its source on the flank of Pu`u `O`o to the ocean, with frequent surface flows breaking out of the tube near the 2,300-ft elevation, and a persistent flow, known as the "March 1 breakout," active on the coastal plain. The March 1 breakout is waning, however, and active lava was limited to a small area 1.8 km (1.1 miles) from the coast.

Lava is still entering the ocean at East Lae`apuki, in Hawai`i Volcanoes National Park. The active lava bench continues to grow following the major collapse of November 28 and is now approximately 1,000 m (3,300 ft) long by 315 m (1,000 ft) wide, with a total surface area of 17 ha (43 acres).

Access to the ocean entries and the surrounding area remains closed, due to significant hazards. If you visit the eruption site, check with the rangers for current updates, and remember to carry lots of water when venturing out onto the flow field.

There was one earthquake beneath Hawai`i Island reported felt within the past week. A magnitude-2.4 earthquake occurred at 6:05 p.m. H.s.t. on Monday, May 29, and was located 2 km (1 mile) northeast of Pu`ulena Crater in Puna at a depth of 3 km (2 miles).

Mauna Loa is not erupting. During the past week, earthquake activity remained low beneath the volcano's summit (one earthquake was located). Extension of lengths between locations spanning the summit, indicating inflation, continues at slow rates.

Visit our web site ( for daily Kilauea eruption updates and nearly real-time Hawai`i earthquake information. skip past bottom navigational bar

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Updated: June 5, 2006 (pnf)