The book I’ve just finished reading – Beyond the Map by Alastair Bonnett, is a vaguely Fortean themed exploration of some of the weirdest and lesser-known places on Earth. One brief section describes the Tsunami stones dotted around Japan’s north east coast. These megaliths, some standing 3 metres tall, have been erected over the centuries and incised with prayers and warnings to future generations not to build houses in areas swamped by Tsunamis in the past. Sadly, they have been largely ignored and some 18,000 people lost their lives in the “3/11” Tsunami in 2011. This Tsunami also wrecked the poorly-located Fukushima nuclear power plant, spreading hazardous material over a wide area. The book then touches on a profound point; how can we warn generations in our far-distant future about dangerous nuclear waste we are storing around the world? Plutonium 239 will remain hazardous for an estimated 220,000 years. That’s an almost unimaginable period to us. So just imagine some curious hominids (who probably look as different from us as we do from Homo Erectus) in the year 20017, are exploring a cave system or maybe some ground disturbed by an earthquake, and come across some mysterious metallic cylinders, partially encased in crumbling concrete? What kind of enduring warning message or symbol would be meaningful to them? The inscriptions on the Tsunami stones are still just about legible and their slightly archaic Japanese can be readily understood. But they are only a few centuries old. In just over 1,000 years, the English of Beowulf has become virtually incomprehensible to us. There is no chance of our mother tongue surviving 200 times that length of time. So what kind of warning can we produce to survive into an unimaginably distant future and to let our unimaginably distant descendants know what a recklessly stupid species we were?