The 1880-1881 eruption of Mauna Loa consisted of two main phases, a summit eruption and a rift zone eruption six months later. The latter was a nearly nine-month-long march that threatened the city of Hilo. Prayers to both Christian and Hawaiian deities were employed to stop its advance.
On the evening of November 5th, 1880, Princess Liliʻuokalani went to sleep on the first night of her stay at the Volcano House hotel on the rim of Kīlauea. She had come to the Kīlauea summit to see the fires of the long-lasting lava lake in the home of Pele. At 2:00 in the morning, she was jostled awake by hotel staff. They alerted her to a startling event. Mauna Loa, looming in the distance, had let loose a ribbon of glowing molten lava that was pouring down its side.
The distant ribbon of light that Liliʻuokalani witnessed from Volcano House was the begining of the second act of the 1880-1881 Mauna Loa eruption.
The first act had begun six months earlier, on May 1st, with an eruption in Moku‘āweoweo, the summit caldera of Mauna Loa. For its first 48 hours, the eruption at the summit was visible from many places on the island. It produced a 10,000-foot (3 km) “column of smoke” by day that was lit by a lava glow at night.
The view of the summit eruption was soon obscured by cloud, but its power was still being felt far below. The sharp fibers of Peleʻs hair drifted into the town of Hilo. Reverend Titus Coan wrote that the town was “in a haze of sulphur smoke, and we see the sun as through smoked glass”
“the astonishing elderly woman has returned to her village at Mokuaweoweo. She has shown her exceptional light, it is evident here in Hilo.”
-S.P. Kalaau, referring to Pele and the initial eruption in the Moku‘āweoweo summit caldera
After six days, the eruption on the roof of Hawaiʻi quieted down, but more activity would follow later that year. All Mauna Loa eruptions in the modern period have started in the summit area. About half of these eruptions, however, are soon followed by eruptions on the volcanoʻs flank along rift zones. As geologist Frank Trusdell has noted, “most summit and rift zone eruptions are separated by minutes to several days,” but in 1880-1881, the rift zone eruption did not begin until an astonishing six months later, “making it the longest summit-rift-zone eruption lag in the recorded history of Mauna Loa volcano.”
Act two, on the Northeast Rift Zone, began on November 5th and it would last nearly nine months. In its first few days, the USGS Hawaiian Volcano Observatory estimates that these flows advanced an average speed of about 3.7 miles per day (6 km).
Soon the eruption had created three flows. One angled northward toward Mauna Kea, a second flowed more easterly toward Hilo, and a third, which Lili’uokalani had seen from Volcano House, descended into Ka’ū. The eruption continued into the new year of 1881, but of the three flows, only the flow that was advancing toward Hilo remained active. The reported source of these flows was Pūkauahi, a cone northeast of the summit caldera, along what is now the Mauna Loa Trail.
Throughout the spring months of 1881, the flow moving toward Hilo continued its slow march, an estimated 6- 8 miles from Hilo. By June, estimates place it between 4-5 miles from town. It also split into several branches.
As the distance between the flow and town decreased, some began to appeal to higher powers: “it is hereby recommended, that on Wednesday the 6th day of July, all places of business in the town and district of Hilo, be closed from 11 A. M. until 3 P. M and that all persons who believe in an Almighty God look to him especially on that day, and so far as practicable, assemble in their several places of worship for that purpose, if so be He may be pleased to avert the threatening calamity, or prepare us for the result” - Governor F.S. Lyman
Despite determined prayers, by July 7th, the northern branch of the flow was 2.25 miles from Hilo, and the southernmost branch 4.5 miles out. One Hilo resident, Keoni Holo, had property on the outskirts of town and made offerings to Pele in the hopes that she would stop her march and spare his homestead: "Aloha o Pele. Mohai ia oe o Pele. Hail to thee, O, Pele. Receive my gift, O, Pele." He offered his finest pig as well as chickens, fruit, and a lock of his own hair at the foot of the advancing flow. But as the Hawaiian Gazette noted, Pele was unabated, “with a puff of steam and a crackling flow of blood red fire, that smothered the squeak of the poor porker”
The lava seemed to advance in pulses, as opposed to a steady rate of movement. By July 27th, one of the branches, now traveling in Kūkūau Gulch, was only 2.15 miles from the sea.
In early August 1881, Princess Ke‘elikōlani (also known as Princess Ruth) and Princess Regent LIli’uokalani arrived to Hilo separately. Princess Ke‘elikōlani, in a now famous scene, reportedly made offerings at one of the flowʻs branches in an effort to appease Pele and stop its advance. At the foot of the flow, the Princess prayed to Pele to return home and offered her brandy and a red hankerchief. According to some reports, that branch of the flow then “stopped at that point and did not flow a foot farther.” Some Hawaiians concluded that Keʻelikōlani was responsible for the flow's cessation.
The eruption also saw the first recorded plans for lava diversion in Hawaiʻi. Although never acted upon, there were formal plans to use dynamite to divert the flow. Other groups constructed stone walls. The Reverend Titus Coan, wrote that, “Judge Severance dug a moat around the Hilo prison, with an embankment seven or eight feet high,” hoping to avert the necessity of a jail evacuation.
The terminus of the flows nearing Hilo were largely considered dead by August 12th, though still active spots could be found further toward the source vents.
To celebrate the end of the eruption and Hilo’s avoidance of disaster, September 18th and 19th were set aside “to praise the Almighty God for His kindness and Compassion in saving the village of Hilo from His Lava’s fiery wrath”. As USGS notes, services included the reading and singing of a hymn about the lava in Hilo. A year later, in August 1882, a large commemorative lūʻau was staged immediately in front of then-cooled lava flow.
According to the USGS Hawaiian Volcano Observatory, the total length of the 1880–1881 Hilo flow is about 29 mi (47 km), and had an average advance rate of about 3.4 mi (5.5 km) per month over the course of the long rift zone eruption. The furthest reaching flow made it to a mere 1.1 miles (1.8 km) from the Hilo bayfront.