If we live on a globe earth then the curvature can be calculated which would show how much the earth curves over a given distance. This is not an assumption, it’s math. The formula for determining the curvature of the earth is that there is an 8 inch drop for every mile squared. You can also Google earth curvature charts to see the tables that have been pre-calculated. If we apply this formula to Texas taking into account the elevations we can compare how much the distance should drop compared to how much it does drop in elevation. This would show us if the earth is flat or a sphere.
Texas is the second largest state in the USA. The distance from El Paso Texas to
Henderson Texas is 770 miles. The elevation goes from 3740 feet to 512 feet, creating
a drop of 3228 feet or about 2/3 mile over this distance. If you calculate the drop on a
globe earth, this distance should create a drop of over 74 miles.
If we go in the other direction from Pampa to Corpus Christi the drop is 3234 feet over
a distance of 648 miles. Using the same formula to calculate the curvature of the earth
over that distance the drop should be over 53 miles.
Obviously, Texas does not exist on a globe earth and neither is the earth a round spinning globe.
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