[Humble B]

Scrolling trough FES' WIKI under the chapter “Circumnavigation” I found this:

Q. What about other types of navigational instruments?

A. Using a compass, gyrocompass, or looking at Polaris as a reference for Eastwards or Westwards travel will take the navigator in a broad circle around the North Pole.

Of course this answer would not be complete without mentioning the Gyrocompass, because since wooden ships were replace with metal ships, the magnetic compass became rather useless and had to be replaced with a non-magnetic compass.

This happened after the first usable gyrocompass was introduced in 1908, a compass based on a spinning gyroscope. How does it work:

When you have a spinning gyroscope, and you push against the axis to change the direction of it, you will feel friction; the gyroscope will push back in the opposite direction of your force. If you fix that gyroscope on the surface of a ball, with the axis of spin horizontally to the surface of the ball, and you start slowly rotate that ball, the spinning gyroscope will start to push in the opposite direction as the spin of the ball is changing the axis of the gyroscope. If you now install that gyroscope in a device that can perceive that force and the direction in which the gyroscope is pushing when it is moved, then that device can show you in which direction you spin that ball.

Now since globelings believe that the earth is also a spinning ball, they came up with the ingenious idea to use that principle of gyroscopes to create a non-magnetic compass, and after long deliberation they called it the “gyrocompass”



Of course FE'ers know better, they know that the inventors of the gyrocompass made a huge mistake by assuming that the earth is a spinning ball and therefore their invention would work, but they can't ignore that the gyrocompass has proven its services successfully for more than a century. Now my question is, how does FET explain the success of the gyrocompass? What on a flat earth makes the gyroscope move in such a way that it shows the geographical directions?

[BillO]

This simple answer is that a gyro compass will not work on a flat earth.  It requires the spin of the planet to correctly orient the gyroscope.  So we can look at two cases for the flat earth.

Case 1)  The flat earth spins about it's north pole.  This won't work for the bipolar model, and most FE's are against the earth's spinning at all.  But f it did, the gyro compass would end up orienting itself perpendicular to the flat earth plain and become useless.

Case 2)  When initially started it is aligned perfectly north and south.  This would work if you only traveled north and south, but if you attempted any amount of travel east to west, the compass would immediately be in error.   Again, totally useless.


So, yet another thing that has worked just fine for many, many years that would not work at all if the earth was flat.

[Rounder]

since wooden ships were replace with metal ships, the magnetic compass became rather useless and had to be replaced with a non-magnetic compass.

This is a misconception.  All modern ships still have a magnetic compass on the bridge, with correcting spheres to compensate for he uneven magnetic field disturbance caused by the vessel’s own materials.  See this Wikipedia article.

[Tom Bishop]

What is the difference between circling the North Pole at a distance of 100 feet from it on a Round Earth vs. a Flat Earth?

1000 feet?

10,000 feet?

If there is a difference, who has documented such a difference?

[sandokhan]

Gyro-compasses and Foucault's pendulum cannot be used to debate geocentrism vs. heliocentrism.

The Coriolis force is responsible for the effects of the gyrocompass.

Here is the derivation of the formula:

https://inis.iaea.org/collection/NCLCollectionStore/_Public/21/068/21068614.pdf

The Coriolis force exists only when one uses a rotating reference frame.

Either the Earth's supposed rotation, OR the ether drift's rotation above the surface of the Earth.

Only a light interferometer, which registers both the Coriolis effect and the rotational Sagnac effect, can answer the question: does the Earth rotate around its own axis, or does the Sun orbit above the flat surface of the Earth?

The formula for the Coriolis effect applied to light interferometers:

https://www.theflatearthsociety.org/forum/index.php?topic=30499.msg2068289#msg2068289

https://www.theflatearthsociety.org/forum/index.php?topic=30499.msg2069660#msg2069660

The formula for the Sagnac effect applied to light interferometers which are located away from the center of rotation:

https://www.theflatearthsociety.org/forum/index.php?topic=30499.msg2070082#msg2070082

https://www.theflatearthsociety.org/forum/index.php?topic=30499.msg2070907#msg2070907



One cannot explain the gyrocompass on a flat earth without resorting to ether field theory.

[HorstFue]

The Coriolis force is responsible for the effects of the gyrocompass.

That cannot be correct. The gyrocompass also aligns to the north direction, when the ship is stopped.
Coriolis force only exists,  when you move radial on a rotating surface/disk/sphere whatsoever.

[sandokhan]

Even if the ship stops, the gyrocompass is still subject to the effects of the rotating ether drift (physical Coriolis effect).

https://maritime.org/doc/fleetsub/elect/chap17.htm

"To be of use as a compass on board ship, the gyro wheel must remain rigidly in the meridian at any latitude and must be unaffected by the ship's motion."

You are going to have to explain why Albert Michelson used the Coriolis effect formula for light beams, while his interferometer (MGX, 1925) did not record the rotational Sagnac effect.

[HorstFue]

Even if the ship stops, the gyrocompass is still subject to the effects of the rotating ether drift (physical Coriolis effect).

https://maritime.org/doc/fleetsub/elect/chap17.htm

"To be of use as a compass on board ship, the gyro wheel must remain rigidly in the meridian at any latitude and must be unaffected by the ship's motion."

You are going to have to explain why Albert Michelson used the Coriolis effect formula for light beams, while his interferometer (MGX, 1925) did not record the rotational Sagnac effect.

I could not find any instance of the words "Coriolis" nor "Ether" in the linked document (unless "together", "whether").
I found the word "Precession", many times.

The Michelson-Morley-Experiment tried to measure the influence of a moving Ether on light. Same thing with Sagnac-Effect: Only light is affected.

[sandokhan]

MGX = Michelson-Gale experiment, 1925

MMX = Michelson-Morley experiments, 1881 and 1887

SGX = Sagnac experiment, 1913

Only light is affected.

Light can affected in two ways (light interferometer): a physical effect (the Coriolis effect upon the paths of the light beams) and an electromagnetic effect (the rotational and orbital Sagnac effects upon the speed of the light beams).

Michelson used the Coriolis effect formula and never registered the rotational Sagnac effect at all.