On 27 August 1883, at 10:02 AM local time when the sound emerged from the island of Krakatoa, which sits between Java and Sumatra in Indonesia. It was heard 1,300 miles away in the Andaman and Nicobar islands , 2,000 miles away in New Guinea and Western Australia and even 3,000 miles away in the Indian Ocean island of Rodrigues, near Mauritius. In all, it was heard by people in over 50 different geographical locations, together spanning an area covering a thirteenth of the globe.
Think, for a moment, just how crazy this is. If youre in Boston and someone tells you that they heard a sound coming from New York City, youre probably going to give them a funny look. But Boston is a mere 200 miles from New York. What were talking about here is like being in Boston and clearly hearing a noise coming from Dublin, Ireland. Travelling at the speed of sound (766 miles or 1,233 kilometers per hour), it takes a noise about 4 hours to cover that distance. This is the most distant sound that has ever been heard in recorded history.
So what could possibly create such an earth-shatteringly loud bang? A volcano on Krakatoa had just erupted with a force so great that it tore the island apart, emitting a plume of smoke that reached 17 miles into the atmosphere, according to a geologist who witnessed it1. You could use this observation to calculate that stuff spewed out of the volcano at over 1,600 miles per houror nearly half a mile per second. Thats more than twice the speed of sound.
This explosion created a deadly tsunami with waves over a hundred feet (30 meters) in height. One hundred sixty-five coastal villages and settlements were swept away and entirely destroyed. In all, the Dutch (the colonial rulers of Indonesia at the time) estimated the death toll at 36,417, while other estimates exceed 120,0002,3.
The British ship Norham Castle was 40 miles from Krakatoa at the time of the explosion. The ships captain wrote in his log, So violent are the explosions that the ear-drums of over half my crew have been shattered. My last thoughts are with my dear wife. I am convinced that the Day of Judgement has come.
Closer to Krakatoa, the sound was well over this limit, producing a blast of high pressure air so powerful that it ruptured the eardrums of sailors 40 miles away. As this sound travelled thousands of miles, reaching Australia and the Indian Ocean, the wiggles in pressure started to die down, sounding more like a distant gunshot. Over 3,000 miles into its journey, the wave of pressure grew too quiet for human ears to hear, but it continued to sweep onward, reverberating for days across the globe. The atmosphere was ringing like a bell, imperceptible to us but detectable by our instruments.
The Krakatoa explosion registered 172 decibels at 100 miles from the source. This is so astonishingly loud, that its inching up against the limits of what we mean by sound.
By 1883, weather stations in scores of cities across the world were using barometers to track changes in atmospheric pressure. Six hours and 47 minutes after the Krakatoa explosion, a spike of air pressure was detected in Calcutta. By 8 hours, the pulse reached Mauritius in the west and Melbourne and Sydney in the east. By 12 hours, St. Petersburg noticed the pulse, followed by Vienna, Rome, Paris, Berlin, and Munich. By 18 hours the pulse had reached New York, Washington DC, and Toronto1. Amazingly, for as many as 5 days after the explosion, weather stations in 50 cities around the globe observed this unprecedented spike in pressure re-occcuring like clockwork, approximately every 34 hours. That is roughly how long it takes sound to travel around the entire planet.
In all, the pressure waves from Krakatoa circled the globe three to four times in each direction. Meanwhile, tidal stations as far away as India, England, and San Francisco measured a rise in ocean waves simultaneous with this air pulse, an effect that had never been seen before. It was a sound that could no longer be heard but that continued moving around the world, a phenomenon that people nicknamed the great air-wave.
Another old structure in Frankfurt that survived WWII. It basically describes how different objects are arranged next to each other for added effect, especially when they contrast. It isn’t necessarily “arranged next to each other”… Juxtaposition means when two things that are utterly different are observed as such. Like, you see a group of nuns walking through the Red Light District or something… or if a solo pianist opened for a death metal band at a concert.