Wisdom of the Ancients
Dec. 23rd, 2019 07:07 pmWhen I gave my talk on the history of non-Euclidean geometry a while back, one of the questions that came up was the ancients' knowledge of the roundness of the Earth. The audience were academics, most of them, but there were a few who were unaware how far back that bit of knowledge goes. I mentioned Aristotle's arguments on the subject, and Eratosthenes' measurement of the Earth.
So, I'm currently reading Pliny's _Natural History_. That's Pliny the Elder, who died during the eruption of Vesuvius that destroyed Pompeii. Thus far, he's mostly been talking about astronomy and meteorology, and most of it's rubbish, although I was interested to find that he knew that light moves faster than sound. (His was the usual argument, involving lightning-flash and thunderclap.) But I just hit a passage in which he presents several arguments for the roundness of the Earth; the most interesting, I think, rests on the visibility of different stars and constellations at different latitudes; I don't think I've run into that one before, although once pointed out it's pretty obvious.
Pliny's going to be a long slog. I'm in what's marked as Chapter 72, apparently 11% of the way into Volume 1 (of 6). The chapters are short, happily.
So, I'm currently reading Pliny's _Natural History_. That's Pliny the Elder, who died during the eruption of Vesuvius that destroyed Pompeii. Thus far, he's mostly been talking about astronomy and meteorology, and most of it's rubbish, although I was interested to find that he knew that light moves faster than sound. (His was the usual argument, involving lightning-flash and thunderclap.) But I just hit a passage in which he presents several arguments for the roundness of the Earth; the most interesting, I think, rests on the visibility of different stars and constellations at different latitudes; I don't think I've run into that one before, although once pointed out it's pretty obvious.
Pliny's going to be a long slog. I'm in what's marked as Chapter 72, apparently 11% of the way into Volume 1 (of 6). The chapters are short, happily.