On 5 April 1815 the crew of the British East India Company cruiser the Benares, anchored at Makassar in Sulawesi, heard what they thought was the sound of cannon-fire, drifting in from the south. The nascent Dutch East Indies had been under temporary British rule for the previous four years, and there had been sporadic unrest across the archipelago. The captain of the Benares assumed that more trouble was brewing, and he set sail to investigate.
But after three days of scouting out pirate hideaways he had found nothing untoward and he returned to port bemused. But then, on the night of 10 April, there were more concussions from the south, “in quick succession, sometimes like three or four guns fired together”. They were so loud, the captain reported, that the Benares rocked back and forth in the calm waters of the harbour. “It was apparent”, he wrote, “that some extraordinary occurrence had taken place”. The captain was right: the crew of the Benares had just heard the sound of the largest volcanic eruption in modern history. Mount Tambora had blown its top.
The Bigger Bang
The 1883 eruption of Krakatau (often misspelt and mispronounced “Krakatoa”) has become a byword for a cataclysmic natural disaster. The Tambora eruption, meanwhile, in the same region – the Indonesian archipelago, the most volatile part of the Pacific “ring of fire” – just 68 years earlier remains little known. But Tambora was by far the bigger bang. It caused thousands of deaths, skewed the global climate, and obliterated an entire language. Krakatau’s eruption sent a paltry 18 cubic kilometres of detritus up into the sky; Tambora, in one monumental concussion, spat 150 cubic kilometres of rock and ash into the atmosphere.
In the early 19th century Tambora was one of the highest of Indonesia’s hundreds of volcanic peaks. It rose some 4,300 metres over Sumbawa, a remote island in the southeast of the archipelago, split into six small principalities, each with its own distinct cultural and linguistic traditions. Tambora rose across the bay from Bima, Sumbawa’s main port, and visiting sailors reported that the peak had been spewing out smoke since early 1814. But it was only on 5 April 1815 that the real trouble began.
The crew of the Benares were not the only ones to mistake the noise of the first eruptions for gunfire. The British officers in charge of the fort at Yogyakarta in Central Java, 500 miles from Sumbawa, despatched a unit of troops when they heard it, believing the neighbouring fort at Klaten was under attack. The thuds were even heard – and similarly misinterpreted – in Bengkulu in Sumatra, more than 1,000 miles away.
But over the coming days the true cause of the sound became clear, as sporadic rumblings continued from the east, and ash began to fall, all over the western half of Indonesia. The weather was ominously overcast, and British residents in Java reported that rumours of earthquakes and revolutions had begun to do the rounds. And then, on the evening of 10 April, came the biggest bang of all, rattling rafters and shivering timbers across Indonesia.
The Darkest Day
By 12 April the main ash cloud had reached Java, and Carel van Naerssen, the official Resident in Gresik in East Java, woke “after what seemed to be a very long night, and taking my watch to the lamp, found it to be half-past eight o’clock”. Ash continued to fall and it got darker as the morning progressed, and when van Naerssen took his breakfast at 11am he had to eat by candlelight.
In Sulawesi, meanwhile, the crew of the Benares had set sail to investigate. They had started from Makassar on the morning of 11 April, and by midday they were sailing in total darkness.
“I never saw anything to equal it in the darkest night; it was impossible to see your hand when held up close to your eyes”, the captain wrote. When a thin and dirty daylight returned the following morning, it showed a foot of ash lying on the deck of the ship, and before long they were creeping through great mats of floating pumice and broken trees. On 18 April they finally sighted the devastated coastline of Sumbawa, and came ashore on an island that had changed beyond all recognition.
Large ships had been tossed high above the tideline; the thick cloaking of forest had been scorched to a grey wasteland, and houses had collapsed under the weight of the falling ash. But the biggest change of all was in Tambora itself: the top 1,500 metres of the mountain had simply vanished.
The crew of the Benares, and a handful of other horrified visitors who arrived in the coming weeks, did their best to collect details of what had happened. The British representative in Bima, a Dutchman called Pielaat, had survived, though his house had been destroyed. The sound of the 10 April explosion, he said, had been like “the report of a heavy mortar close to his ear”.
The most thorough account of what had happened came from the Raja of Sanggar, one of the little principalities that lay close to the volcano. After a week of fuming furiously, he said, the mountain had simply exploded:
“[T]hree distinct columns of flame burst forth, near the top of Tomboro [sic] Mountain, all of them apparently within the verge of the crater; and after ascending separately to a very great height, their tops united in the air in a troubled confused manner. In a short time the whole mountain next [to] Saugar [sic] appeared like a body of liquid fire extending itself in every direction.”
The eruption was accompanied by a 12-foot tidal surge, a downpour of fist-sized rocks, and a violent wind “which blew down nearly every house in the village of Sanggar”.
But at least the Raja and some of his subjects had survived: two other little kingdoms that had lain at the western foot of the mountain had been wiped from the face of the earth. Pekat and Tambora, their rajas Muhamad and Abdul Gafur, and some 10,000 other people, had been vaporised. Tambora, the little state that took its name from the mountain, had had its own unique language; in a single day it had vanished, along with all its songs, legends and folk literature.
Rice crops across Sumbawa had been obliterated, and within days famine and dysentery had broken out. Around 37,000 people died of disease and starvation in the coming months, and locals took to selling themselves as slaves to pirates from Sulawesi just for a chance to be carried away from their accursed island. Within a year Sumbawa’s population had been cut by at least half.
The Year Without Summer
But Tambora’s trail of destruction stretched beyond its immediate impact zone. That great, sky-obscuring ash cloud had crept out across Indonesia, wreaking havoc as it went. The islands immediately to the west of Sumbawa suffered the most. All the farmland in neighbouring Lombok was ruined, and as much as half of the population died in the consequent famine. In Bali too there was devastation, and crops across East Java were poisoned by the ash. In all, perhaps 100,000 people died in Indonesia as a direct consequence of the Tambora eruption.
And the volcano’s cataclysmic reach went far beyond Southeast Asia. Those 150 cubic kilometres of detritus had lifted on the thermals, filtered out across the globe, and set the global weather patterns spinning. The following year there were frosts in Europe in June; the French grape crop failed, cholera broke out in India, snow fell in New England in July, and in Switzerland people took to eating stray cats to survive the chronic food shortages. They called it “the year without summer”.
Six decades later, when Krakatau produced its own comparatively modest cataclysm colonial infrastructures and international communications networks were far more advanced. That eruption turned into an early global media event, and it was certainly one of the first natural disasters to make headline news around the world. But its scale and impact were nothing to the effects of the truly monumental explosion that rocked Sumbawa, Indonesia and the world in 1815. Really, it should be “Tambora”, not “Krakatau”, that is synonymous with unsurpassed volcanic violence.
Tim’s book Raffles and the British Invasion of Java, 2012, is published by Monsoon Books.