Isaac Newton (1642-1727) developed an inverse=square law of gravitation between two masses. How to test it?

Newton knew that, just as walking is falling, but catching yourself with the other leg before you fall, so the moon can be thought of as falling toward the earth, but going fast enough to orbit the earth. So his law could predict where the moon would "rise" at night in his neighborhood. So he consulted astronomincaltables and made calculations. But this didn't agree with his law, so he put his law aside for the time being.

A long time later, Newton was in a book shop where he often went. He noticed a new edition of atronomical claculations and glanced at it. The figures for moon rising reminded him of something.

Forgetting to pay for the book or explain, Newton rushed out of the shop to go home. There, he found that the corrected data of this book fit his calculations. So he published his Law with The Royal Society, and the rest is history.

Supposedly, he later paid for the book.