I approve of cynicism. And since I read this a LONG time ago, 10 years
ago at least...

I dug through my book collection to find my Map-making book. The
title is "The Story of Maps" by Lloyd A. Brown, published in 1949.
Excellent reading for the technical minded. On page 224 I found the
reference I mentioned. The reference to gravity was by Isaac Newton,
the experiments regarding the clocks were performed by Jean Richer,
with Cassini and Huygens critically examining the results. The year
was 1673. Newton was quoted as saying the change in clock rate was due
to "a diminution of gravity resulting from a bulging of the earth at
the equater, or from the strong counteracting effect of centrifugal
force in that region"

Many of our ancestors were incredibly sharp...

Speaking of sharp... there was a show on TV about a month ago about a
lost and re-discovered book of mathematics written by Archimedes. It
seems that he had discovered the calculus about 200-300 BC. That
predates Newton by 1500 years or so. Loss of the book, it was claimed
"set mathematics back 1000 years"