186) “People sensitive to motion sickness feel distinct unease and physical discomfort from motion as slight as an elevator or a train ride. This means that the 1000mph alleged uniform spin of the Earth has no effect on such people, but add an extra 50mph uniform velocity of a car and their stomach starts turning knots. The idea that motion sickness is nowhere apparent in anyone at 1000mph, but suddenly comes about at 1050mph is ridiculous and proves the Earth is not in motion whatsoever.”

Already covered in point 121 and point 122, this is also the previous point repeated:

Since Mr Dubay loves to repeat himself, it seems I will have to, as well.

I’ve already answered “we can’t feel the Earth moving.”’ Again, we never feel movement; we feel changes in movement. If we were in a very smooth and silent train, running down very even unjointed rails on a dead-straight track at an unchanging speed, we wouldn’t feel or hear a thing. If the blinds were closed, we could not tell that we were moving at all.

Of course, no real vehicle is every that perfect; there are always some little jiggles or sways, at least. But the Earth doesn’t rest on a road, or run on rails. It moves at a constant pace and a constant course through the empty vacuum of space. What is there to jiggle us?

When we feel the motion of a car, it's because the driver has turned  the wheel, or braked or accelerated, or because an unevenness in the road made the car lurch sideways or up and down. None of these changes in course or speed happen to the earth. So there is nothing for us to feel.

Dubay says; "This means that the 1000mph alleged uniform spin of the Earth has no effect on such people, but add an extra 50mph uniform velocity of a car and their stomach starts turning knots."

.

But it is not the extra 50 mph in itself that causes sickness, but the smaller repeated swaying, jiggling, turning motions, which confuse the motion-sensitive parts of our inner ears. There's nothing in space to cause the earth to make such small jumps, swerves and wiggles, so there is no motion sickness.

When we feel motion, it is because there are tiny hairlike sensor in our semicircular canals 

(http://www.asha.org/public/hearing/How-Our-Balance-System-Works/)  in our inner ears, immersed in fluid. When the fluid is jiggled, the hairs pick up the motion and transmit a signal to out brains, so that we feel the sensation of a change in the direction or rate of movement.  But the earth never changes direction or jolts , so what is there to feel?

Anticipating a misunderstanding: yes, the path of the earth is a curve (an ellipse –nearly but not quite a circle). But that won’t give the sensation of “turning a corner. The orbit of th earth is as it is precisely because it is an exact balance between the gravitational attraction of the sun and the outward effect of ‘centrifugal force (actually inertia. And the strength of both of these is constant over time, so there is no change for your inner ear to sense.

http://www.asha.org/public/hearing/How-Our-Balance-System-Works/