Perboewatan

"Perboewatan" (also spelled Perbuatan; apparently a Malay word of uncertain dervivation) was one of the three main volcanic cones (the others being Danan and Rakata) on the island of Krakatoa (Krakatau), in the Sunda Strait, in Indonesia. It was the lowest (400 ft) and northernmost of the cones. Perboewatan was completely destroyed in the 1883 eruption; the caldera is approximately convert|1800|ft|m deep where it had been.

Form

Perboewatan is the only cone on Krakatoa that there is a good pre-1883 photograph of; made on May 27, 1883, by visitors to the island. In the photo it appears to be a low hill with a flat top. Climbers reported the erupting crater to be about convert|3300|ft|m across at the top, narrowing to 150 at the bottom and 500-800 feet deep. Samples were collected and on analysis, revealed a silica (SiO₂) content of 65%.

Eruptions

1680-81

Perboewatan was seen to be erupting by at least two travelers through the straits in the 1680-81 period. Johann Wilhelm Vogel, a mining assayer, was told that the eruption had begun in May, 1680. Apparently Danan also erupted later, and the eruption apparently lasted through February of 1681, when both were seen in eruption by Vogel.

The 1883 Catastrophe

Perboewatan started erupting on May 20, 1883, being previously thought to be extinct. On May 27, 1883, the GG Loudon took a sight-seeing group of about 90 to Krakatoa, landing on the northern end of the island, just below Perboewatan. Several in the party climbed up to the crater, which was still erupting. As the ship was leaving, a photographer took several photos of the erupting volcano.

In R. D. M. Verbeek's reconstruction of the eruption, Perboewatan is thought to have been the first cone destroyed, at about 4:40 am, August 27.

References

Furneaux, Rupert; Krakatoa (1964)