November 18, 1865 Tsunami: Tonga Islands

1865, November 18 05:40 local time. 19.5 S, 173.5 W, magnitude 8, tsunami intensity 3. On the 18th at 04:20 the English ship "John Wesley" ran aground near the small island (a coral reef) of Tau, but after several earthquake tremors was refloated completely. The ocean raged with such force that waves enveloped the deck.

At 05:40 there was a strong earthquake and the waves became even more dangerous. Twenty minutes later a terrible crack was heard on the ship and it immediately filled with water and sank in a depth of 1 m (3 feet), but the crew and all the passengers were saved.

The earthquake affected a huge area. It was severe on the islands of Haapai and rather severe on the island of Lifuka and Vavau, where furniture was displaced and the pendulums of clocks were stopped. On the open sea at 24 deg S. and 173 deg 30 min W. , similar vibrations were experienced on the American ship "Siren" on the 18th at approximately 06:00 accompanied by a muffled rumble.

On the Tonga Islands, the earthquake was accompanied by a "sudden and violent movement of the sea," flooding the land and washing away everything in its path.

By 09:20 of the 18th in Avarua, island of Rarotonga (Cook Islands), in good weather with a light south-east breeze and at low tide, the sea had gradually receded to approximately 1 1/4 m (4 feet) below the usual low water mark, almost completely draining the water area of the port. Then the level of the water gradually rose 1 1/4 m (4 feet) above the highest flood tide, but there was no evidence of waves. The rise and fall occurred while the water surface was completely calm. The sea fell and rose to the same levels a second and a third time. Then, in the course of a half hour, the oscillations diminished and the sea became still and assumed its normal level.

(above from reference #415)

1865, November 18, 05:40? Generating area Tonga, observed in Tau, Tonga Islands, Cook Islands (1.2 m, travel time 3.7 hours). Waves wrecked "John Wesley" on reef. Water level oscillations between 4 ft. below normal low tide and 4 ft. above normal high tide. No wave form noticed. Sieberg gives Cook Is. measurements as 4 m. instead of 4 ft. (reference #79)

This wave that saved our precious husbands [on the ship "John Wesley"], went far inland at some of the islands-washed the dead out of their graves - destroyed twenty houses, a boat, and two canoes. The sea receded fourteen miles at some places. (reference #8718)