Dear John,

you did not comment (or criticise) my observations, which are on the Fig.4.22. Your arguments are of the same sort as was in 18-th century by French Academy of Science that the bodies of greater density than air can not fly. It was the mainstream opinion. You are on the same side of the up-to date mainsteram. Neverthless, airplanes can fly, the Earth is not plate, earthquakes are sometimes triggered by tides and are predictable.