How a book written in 1910 could teach you calculus better than several books of today

[pirsquared]

28. 2 high tides every day: Theory of Gravity disproved! Flat earthers confused.

There is an annotated version that explains many of the jokes:
https://skepticalteacher.wordpress.com/tag/ellery-schempp/

"The existence of tides is often taken as a proof of gravity, but this is logically flawed. Because if the moon’s “gravity” were responsible for a bulge underneath it, then how can anyone explain a high tide on the opposite side of the earth at the same time? Anyone can observe that there are two-not just one-high tides every day. It is far more likely that tides were given us by an Intelligent Creator long ago and they have been with us ever since. In any case, two high tides falsifies gravity.

"The gravitational force(1) depends upon the mass of each object and upon the distance between the objects. The closer they are to each other, the more strongly they attract. In the case of the moon and the earth, the moon pulls the ocean water on the nearer side of the earth more strongly than it pulls the rest of the earth, so the water forms a bulge. On the far side of the earth, the water experiences the least pull because it is farthest from the moon. The rest of the earth is pulled away from the far-side water, leaving a bulge of water opposite to the moon, though this bulge is not quite as large as the first one.(6) The moon holds these bulges (more or less) in place while the earth rotates beneath them. The net effect is the tides we experience at the seashore. By the way, there are also small land tides--these are about a centimeter."

A very complete explanation of the tides is presented here.(7)
http://www.coops.nos.noaa.gov/restles3.html
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footnotes:
(5) Observant readers might ask, if the earth-moon center of mass
system is constant in its path around the sun (ignoring perturbations
from Jupiter, et al.), then doesn’t the earth wiggle a little in its
path? The answer is yes, the ripple in the earth’s path is similar to
that from above, but even smaller. The center of mass in the
earth-moon system is about 1000 miles under our feet (when the moon is overhead), or about ¾ of the way from earth’s center.

(6) High and low tides often have a time delay from when the moon is
overhead. For example, it takes 2-4 hours to fill/empty San Francisco
Bay through the Golden Gate. Cf. high tide on the Pacific side of the
peninsula vs. San Jose.
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The author of this parody on creationists is Dr Ellery Schempp--who originated the landmark Supreme Court case that stopped Bible-reading and prayer in public schools (1963). See Wiki.