(Roughly) Daily

From Bartosz Ciechanowski (who brought us the remarkable interactive explainers of how mechanical watches, GPS, and so many more things work), a piece on sound…

Invisible and relentless, sound is seemingly just there, traveling through our surroundings to carry beautiful music or annoying noises. In this article I’ll explain what sound is, how it’s created and propagated…

And so he does– beautifully: “Sound,” from @BCiechanowski.

* Dejan Stojanović

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As we listen, we might recall that on this date in 1811– in the Mississippi River Valley near New Madrid, Missouri, there was a very loud noise: the largest series of earthquakes in U.S. history began; by the time it was complete, it had raised and lowered parts of the Mississippi Valley by as much as 15 feet and changed the course of the Mississippi River.  The earthquakes– measuring as high as 8.6 magnitude on the Richter scale– were felt strongly over roughly 50,000 sq. mi., and moderately across nearly 1 million sq. mi.  The 1906 San Francisco earthquake, by comparison, was felt moderately over roughly 6,200 sq. mi.

Remarkably, there were no (known) fatalities.

“The Great Earthquake at New Madrid.” a nineteenth-century woodcut from Devens’ Our First Century (1877) source