Oobleck is a mixture of cornflour and water (similar to uncooked custard). This liquid is a runny goo until you apply stress to it, and then it suddenly acts like a solid. You can hit a bowlful with a hammer, and instead of splashing everywhere, the particles lock together. You can roll it into a solid ball in your hand, but if you stop moving it, it reverts to liquid and oozes out through your fingers.
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Since the introduction of the modern clock, telling the time is a non-issue. However, just imagine before the invention of the mechanical clock, when there were only rudimentary methods of telling the time.
In the past, one of the most popular methods of telling the time was by using a 'candle clock' that burned fairly reliably at a set pace past defined markers that indicated the time.
It was even possible to create a makeshift alarm by inserting a nail into the candle at the desired interval. When the wax around the nail melts, it would drop onto the metal plate below and make a noise.
There's no certainty over when candle clocks were first used, but they are no longer in use today, having being superseded by the mechanical clock. The earliest known reference to candle clocks was by You Jiangu in 520 CE.
Normandiya'daki bu eski ikinci dünya savaşı Alman sığınağı D-Day'den hemen sonra bulundu ve savaştan sonra bir gece kulübüne dönüştü. Uzun zamandır terkedilmişti ama içeriye bir bakış attı. Büyüleyici bir yer!———This old world war2 German bunker in Normandy was captured just after D-Day and turned into a nightclub after the war. Long since abandoned but managed a look inside. Fascinating place! #ww2#ww2history#ww2memes#world#ww2history#worldwar2