If we use deduction then we can look at the simple fact that Earth is a globe, and conclude that the meaning of the word circle in Isaiah 40:22 is sphere. In this case the Hebrew word translated as circle also means sphere.
Compass: Focus and Circumference
The third clue that helps us to deduce the creation of gravity comes from a verse in Proverbs 8. It's part of a passage which runs from verse 22-31 and is a synopsis of the account of creation.
Hypothesis 21
We use the change from formless to formed, the appearance of the orientation under and above, and the analogy of a drawing compass having a focus and circumference to deduce that gravity was created on the second day.
Gravity is a Field Emitted from the Center of the Earth
Axiom II is "Gravity is a Field Emitted from the Center of the Earth." We can deduce Principle I from the following physical evidence, empirical observations or established theories which are part of Axiom II.
The ISS isn’t Zero-G
If Earth is the center of gravity of the observable universe, then the observable universe is in the gravitational field of Earth. The strength of the field is inversely proportional to the square of the distance from Earth.
Gravity
The Bible contains an extensively developed doctrine of gravity but it's not new, it's always been there. It may be new to you, but it was here already, long ago; it was here before our time.
The Four Corners of the Earth
The phrase "the four corners of the earth" occurs a few times in scripture but every time it's in the context of the millennial kingdom, it's never used in any other context.
Above and Below
A recurring theme in scripture is heaven above and Earth below. Orientation occurs for the first time on the second day. It's an ordering of the universe which occurred in response to the creation of gravity.
Gravitational Time Dilation
The Bible predicts time dilation as observed. It is caused by the operation of gravity according to our axiomatic definition, which is congruent with practical mathematical applications.
Flat Earth Induction
There's a side effect to the creation of gravity that's going to upset some people: if the Earth formed around a gravitational singularity then it's spherical. It's impossible for the Earth to be flat.