Wikipedia kindly tells me that:
By timing the echo (0.36 s) and measuring the distance (63 m) to and from the end wall of the cloisters, Newton was able to estimate the speed of sound. I have been told that he timed the sound by adjusting a clock so that it ‘ticked’ once in just the same time as it took the sound to travel along the cloisters. Then he let the clock run next to a clock that ticked in real seconds to see how how long it took for (say) 100 ticks.
But imagine if he, like me, had an Apple iMac?
He would have measured the distance by using Google Maps:
He would have measured the time by simply recording the event and analysing a slowed down version in iMovie.
If he had made a precision measurement he would have discovered his theory about sound was wrong. But he didn’t, and he thought his measurements confirmed his ideas. If only he had had an Apple iMac!
Below is a movie of the very cloisters where Newton performed this experiment – and the door at the end is where he lived – and in which rooms he created ideas that changed how we all see the world. Enjoy. Many thanks to Matthew and his friends for a nice day out.