The Last Volcano

by John Dvorak

  Later calculations based on this seismic record would show that the ground surface around Washington, D.C., that morning had vibrated back and forth nearly half-an-inch, though the rate of the vibrations had been too slow—each swing back-and-forth had lasted a few seconds—for anyone to notice. That is anyone except Marvin who had the seismic record to prove it. Moreover, as it was soon determined, the source of the vibrations had been a train of seismic waves that had originated a continent away and had been caused by an earthquake near San Francisco. The seismic waves there had been so strong that some of the city had been destroyed. It took more than an hour for news of the devastation to arrive in Washington, D.C., via telegraph. The seismic waves had made the passage across the continent in just seventeen minutes.

  Intrigued by what he had seen on the seismograph, Marvin began immediately to lobby Congress to make seismological studies a part of the work of the Weather Bureau. It took years of such work to convince Congress. Not until 1914, a year after Marvin was appointed Chief of the Weather Bureau, did Congress approve his request. Less than a year later, by geologic coincidence, Mount Lassen, a volcano in northern California, exploded, setting forest fires and sending up a column of volcanic ash that was seen for hundreds of miles. That event caused Marvin to set his sights on expanding the work of the Weather Bureau to include volcanoes.

  Marvin brought Jaggar twice from Hawaii to Washington, D.C., to testify in front of Congressional committees in support of expanding the Bureau’s work. In May 1918 both the House and the Senate acceded to the request and voted to include the study of volcanoes in the Bureau’s work, but with a provision: The country was then at war in Europe, and so, because war brings uncertainty, Congress mandated that no funds would be approved for volcano work until the war ended.

  That came on November 11, 1918. Two months later Congress approved the first federal funds for volcano research. On February 15, again with the approval of Congress, the Hawaiian Volcano Observatory became part of the federal government. Jaggar continued as the director. And Marvin sent one of the Bureau’s longtime employees to be his assistant.

  Ruy Herbert Finch was a gangly fellow. He stood nearly six feet tall and weighed barely 160 pounds. He had joined the Weather Bureau in 1910 at age twenty, serving at six different stations during the next four years. Each transfer to a new station was at his request. “This man does not like to be tied down to one location,” wrote one of his supervisors. In evaluating his work, the same supervisor wrote that Finch was “too hurried for accuracy” and “had a roving disposition.” Neither characteristic was desired by an organization that prided itself on accuracy and where most of the work was routine.

  Finch was admonished officially at least once for his carelessness, a note in his personnel file reading: “The [afternoon] telegraphic report of June 9, 1913, contains an error in connection with barometric observations, the THIRD of its kind made by you within the past six months.” But Marvin, now Chief of the Weather Bureau, saw promise in Finch. In 1915 he transferred Finch to Washington, D.C., and gave him a new assignment: the writing of seismological reports.

  The new work fascinated Finch, so much so, that the twenty-five-year-old enrolled in nearby George Washington University to study physics. He was one year from graduation when, in 1918, the United States entered the First World War.

  Finch enlisted in the United States Navy and was sent immediately to Ireland to be a weather forecaster and to help work out a scheme so that Navy pilots could spot German submarines in all weather conditions. Finch flew several times as an observer, but he never spotted a submarine. Others in his group did and, subsequently, nine submarines were sunk.

  As soon as the war ended, he was sent to New York to wait for his discharge. He wrote to Marvin, asking if he might contact Finch’s commanding officer and tell him that Finch’s services were much needed at the Weather Bureau. “It won’t hurt if you have to contort the truth,” Finch added.

  Finch got his early discharge. And Marvin offered him a choice. He could continue his university studies and become a researcher and administrator in Washington, D.C., or, because of his previous work on seismological records, he could move to the Hawaiian Islands and assist Jaggar at Kilauea. Finch, a young man who was still restless, chose the volcano.

  He arrived on August 3, 1919, certainly surprised by Jaggar’s latest undertaking. Jaggar had stationed himself at the edge of the lava lake and was in the middle of what he would later say was “by far the most interesting experience I ever had with volcanoes.”

  It was well known that ocean tides rise and fall twice a day because of the gravitational attraction of the sun and the moon. The question that Jaggar was trying to answer was: Might the lava lake at Kilauea also have tidal oscillations?

  He began his lava-tide measurements at noon on July 21. Then, for the next twenty-eight days, one complete lunar cycle, he measured the height of the lake every twenty minutes using a surveyor’s transit to determine the vertical angle between the top of the lake and white marks he had painted high on the crater wall. Measurements were day and night, regardless of weather or volcanic conditions.

  It was a herculean task. And Finch arrived right in the middle of it. The lava lake then consisted of three circular pools, each one more than a thousand feet across, the pools positioned like the leaves of a three-leaf clover. The lake was then at its highest stand in more than twenty years, just a few feet below the crater rim. Jaggar set up the transit near the crater’s edge. He had a shelter constructed to protect the transit from direct sunlight and from rain. It consisted of a large square piece of canvas held up by four heavy timbers. Occasionally, because of the heat of the surrounding solidified lava, one of the timbers caught fire. When that happened, the flames were doused by someone grabbing one of the pots of boiling water that were scattered around and used for cooking.

  Jaggar was assisted by Isabel and by two young men who were visiting from Boston. One of the young men had told his father that he wanted something exciting to do while he was in the Hawaiian Islands. The father suggested that his son contact Jaggar.

  Finch joined the other four in making the measurements. Jaggar worked out a schedule so that each person took a turn at reading the transit, resting, working as the recorder, and resting again. A bed with an iron frame was brought from the Volcano House so that they would have a place to lie down. The iron frame became so hot that heavy blankets had to be thrown over it to keep the occupants from getting burned.

  Guests from the Volcano House came down at all hours of the day or the night to see what was happening. One of those guests who was particularly talkative and who peppered Jaggar with questions asked if the work was dangerous. As Jaggar remembered it, before he could answer, “I heard the hiss of escaping gas behind me and the pounding noise of highly charged lava. At the same time a bright flow spread over the landscape.” He and the guest turned just in time to see “a fountain of liquid fire spurting” from a crack a few hundred yards away. The guest, suddenly quiet, did not wait for an answer to his question. Instead, he departed immediately and, so Jaggar was later told, checked out of the hotel and left the island.

  In all, more than 27,000 measurements of the level of the lava lake were made during the twenty-eight days. In his assessment of the measurements, Jaggar was certain that they “reveal the extraordinary truth that a systematic tide lifts the lava in Kilauea crater so that the liquid is high in the forenoon and low in the evening.” Others who studied the same measurements were not so certain.

  Ernest Brown of Haverford College in Pennsylvania, an authority on the motion of the moon and the calculation of tides, heard of Jaggar’s accomplishment and wrote to him, asking if he could examine the measurements. Jaggar sent a copy of all 27,000 measurements to him. In his final assessment Brown praised the volcanologist for conducting work “with the greatest care and under difficulties which can readily be imagined.” But Brown had come to a different conclusion. After the application
of his considerable mathematical skill, Brown saw no evidence of a lunar tide and thought the vertical movement of the lake level by the moon’s gravity was no more than “an inch or so.”

  In other words, if a lava tide did exist, it could not have been detected by using a surveyor’s transit.

  The first written description of the lava lake was by Reverend William Ellis, an English missionary, who visited Kilauea in August 1823. He traveled to the volcano with eight Hawaiians and three local missionaries. Of this first recorded trip, Ellis wrote: “After walking for some distance over a sunken plain . . . we came to the edge of a great crater, where a spectacle, sublime and even appalling, presented itself before us.”

  Covering the floor of the crater was “one vast flood of burning matter, in a state of terrific ebullition, rolling to and fro.” Ellis watched in awe as an “agitated mass of liquid lava, like a flood of melted metal, raged with tumultuous whirl.” He asked the Hawaiians how long this had been going on. They answered that the volcano had been active from the beginning of time, in their words, mai ka po mai, “from chaos till now.”

  The first hint as to how Kilauea worked was recorded by Reverend Artemus Bishop who visited Kilauea with Ellis in 1823 and returned and saw the lava again 1825. The scene had changed greatly. The caldera—the “sunken plain” mentioned by Ellis—was much shallower, filled, by Bishop’s estimate, with more than four hundred feet of recently erupted lava. John Honoli’i, who had been raised on the island, was with Bishop and informed the Reverend that “after rising a little higher, the lava will discharge itself towards the sea through some aperture underground.” Such a “discharge” of lava did occur years later.

  Titus Coan, an American missionary who lived on the island for many years, was on Oahu when the event happened. When he returned he was told what he regarded were fanciful tales of “the fiery matter” at Kilauea raging “like an ocean when lashed into a fury by a tempest” and of the ground shaking “with maddening energy.” He went immediately to the summit to discount such claims.

  He was surprised by what he saw. He had been to the summit of Kilauea several times, but, now, as he wrote, “Not a particle remains as it was when I last visited.” The lava lake was gone and in its place was a deep steaming crater. He was told that many miles to the east lava had gushed out and flowed into the sea. Again he went to investigate.

  It took him days to make his way through a dense forest. Finally, he arrived at a spot where the crust of the earth had been broken by fissures. And from those fissures had erupted a “mighty smoldering mass” of fresh lava.

  He traveled in the direction the lava had flowed, finding that it led to the sea, as Honoli’i had predicted. Here Coan imagined what the scene must have been just weeks earlier, the lava “leaping a precipice of forty or fifty feet, poured itself into one vast cataract of fire into the deep below, with loud detonations, fearful hissings, and a thousand unearthly and indescribable sounds.”

  Now, eighty years later, Jaggar was devoting himself to Kilauea, watching and recording every change. Though he had failed to detect a lava tide, the next events would be easy to record because of the scale of activity. And because the volcano was, quite literally, ready to explode.

  Jaggar had two ways to record the underground movement of molten lava. One was with the Bosch-Omori seismograph that, of course, could record earthquake shaking. It could also indicate a slight rise or fall of the ground surface by recording the accompanying slight tilting of the surface. To recall, it did this because the horizontal arm worked like a free-swinging hinged door: If the foundation of a house settles, the direction a hinged door hangs will shift. Likewise, if the surface of the ground tilts, ever so slightly, the rest position of the horizontal arm of the Bosch-Omori seismograph shifts.

  The other way Jaggar could know that molten lava was moving underground was to use the lava lake as a giant pressure gauge. If pressure increased inside Kilauea, say, by the inflow of molten lava, then the level of the lake would rise. Conversely, if the pressure decreased, the level would fall.

  The lake level was low after November 28, 1919, the night when Isabel had seen the red glare of the lava lake go out, indicating a sudden drop in the level of the lake. That was followed by more than two years of a general rise in the lake level. By the end of March 1922, the lava level was 178 feet below the crater rim. At the end of April it was only 57 feet, and on May 12 it was 49 feet. The next day a crisis began as the level started to drop.

  “The sinking was steady but majestic,” wrote Thomas Jaggar of the beginning of the event. His wife was more animated in her description. “The whole thing slipped down bodily like a plug rapidly enough but gradually and steadily so that [the floor of the crater] did not break up as it does in some subsidences.” The slow collapse continued for several days. “Then it began to go down faster,” wrote Isabel, “and we were thrilled.” The Bosch-Omori seismograph recorded hundreds of earthquakes. Thomas and Isabel Jaggar went to stand at the edge of Halema’uma’u, to watch the collapse, enjoying it, as Isabel wrote, “When we weren’t jumping back from the edge on account of the shaking of the ground.”

  Molten lava was last seen at the bottom of Halema’uma’u on May 20. And the floor of the crater continued to drop.

  Attention was now drawn to the Bosch-Omori seismograph, which, like a hinged door, was seeking a new position of equilibrium, meaning, the ground was literally tilting beneath it.

  From today’s perspective, it is easy to overlook the importance of recording this movement—an indication the entire summit of Kilauea was subsiding and that molten lava was moving out of a underground summit reservoir and into another part of the volcano. But this was the first time anyone had measured such a subsidence as it was happening. Yes, Omori had measured a net subsidence after two eruptions, at Usu in 1910 and at Sakurajima in 1914, but not as either eruption was occurring. And then Jaggar succeeded at the next challenge: to record the slow refilling of a summit reservoir with molten lava. In fact, Jaggar would measure this cycle several times, setting the foundation for how volcanoes worked—thanks to the cycling of molten lava through reservoirs beneath the earth’s surface—and, thus, providing inspiration for a countless number of future science fair projects by grade-school children who demonstrate how volcanoes work by inflating and deflating a balloon inside a papier-mâché mountain.

  The summit of Kilauea was still subsiding on May 28 when, at about 8 P.M., the slow rumbling of an earthquake was felt across the entire island. Two hours later the Jaggars had just gone to bed when, as Isabel remembered it, “some people who live a mile down the road came to tell us that a glow could be seen in the sky.” It was not coming from the summit crater, but far to the east within a dense forest. The Jaggars dressed and roused Finch who was staying at the Volcano House. The trio headed for the hotel’s garage to get the observatory’s automobile—Marvin of the Weather Bureau had purchased one for them—but there was a delay: The fan belt was broken. It took an hour to mend it by the light of a lantern.

  They drove as close as they could get to the eruption, then found a trail that they followed until it turned away from the direction of the red glow, and, finally, blazed their own trail that took them over cracked ground and through dense obstructing vegetation, each person carrying and navigating with a kerosene lantern. They were chilled by a cold drizzle, got lost several times and were not at all sure where they might emerge. Finally, by 3 A.M., the three stood on the edge of one of the many small craters on this side of Kilauea. As they looked down, they could see a long line of spouting fountains midway on the crater wall from which a dozen ribbons of lava poured down. They spent the night on the edge of the crater, the rain continuing to fall, watching a puddle of lava accumulate on the crater floor.

  “It was a beautiful sight,” Isabel later recorded, “but was not large in extent nor very violent in action.” In fact, it was so mild “that volcanologist Tom said that he thought it would be of short duration.” And
it was; the eruption ended soon after sunrise.

  When they returned to the observatory, there was more excitement. The floor of Halema’uma’u was still dropping and was now nearly a thousand feet down, the deepest yet recorded, hundreds of feet deeper than after the collapse in 1894. Now the sides of the crater were caving inward, causing huge cauliflower clouds of ash and steam to rise from the crater.

  “The old rocks of the walls began to go,” wrote Isabel, “falling in with a roar that could be heard two miles away.” Without sleep, the Jaggars spent the next day at Halema’uma’u, eating their lunch next to the crater. While they were eating, a large cloud floated directly over them and sprinkled them with volcanic ash. As it did, familiar with the story that almost everyone heard when they first came to Kilauea, Isabel “tried to imagine how the [Hawaiians] felt when many of them were overtaken, and some of them destroyed in this same region of the fall of the identical ash, gravel and pumice on which we were sitting.” She was referring to the local story of a huge explosion of Halema’uma’u that eyewitnesses described as “a wonderful fire pillar standing in the sky, and at the top of this pillar a flame of fire was flashing, a flashing as of lightning.” She wondered if what she was seeing now might be a forewarning of a dangerous explosion to come.

  The eruption in the forest ended after one day. And the collapse of Halema’uma’u and the broad subsidence of the summit of Kilauea stopped after another week. Then molten lava returned to the crater. And the summit started to rise, indicating a refilling of the buried reservoir. The next year, in August, there was a repeat of the May 1922 event: collapse of Halema’uma’u, subsidence of the summit and an eruption on the lower slope of Kilauea, far from the summit. Again clouds of ash and steam rose from the crater. And molten lava again refilled the crater.