By studying how the stars are distributed on the sky, he showed that many more stars appear as pairs or groups than could be accounted for by random alignments. Michell was also the first to apply the new mathematics of statistics to astronomy. Using the measured value of the constant, Cavendish was able for the first time to calculate the mass and the average density of the Earth. The measurement yeilded a fundamental physical quantity called the gravitational constant, which calibrates the absolute strength of the force of gravity everywhere in the universe. Cavendish, who actually carried out the experiment after Michell’s death, gave him full credit for the idea. Michell conceived the experiment and built the apparatus to measure the force of gravity between two objects of known mass. This work earned him election in 1760 to the Royal Society, an organization of leading scientists. Michell suggested that earthquakes spread out as waves through the solid Earth and are related to the offsets in geological strata now called faults. After the catastrophic Lisbon earthquake of 1755, he wrote a book that helped establish seismology as a science. In 1750, Michell showed that the magnetic force exerted by each pole of a magnet decreases with the square of the distance. The range of his scientific achievements is impressive.

Michell had numerous scientific visitors at Leeds, including Benjamin Franklin, the chemist Joseph Priestley (who discovered oxygen), and the physicist Henry Cavendish (who discovered hydrogen).

No portrait of Michell exists, but he was described as “a little short man, of black complexion, and fat.” He became rector of Thornhill, near Leeds, where he did most of his important work. Michell was born in 1724 and studied at Cambridge University, where he later taught Hebrew, Greek, mathematics, and geology. Although he was one of the most brilliant and original scientists of his time, Michell remains virtually unknown today, in part because he did little to develop and promote his own path-breaking ideas. This astonishing idea was first announced in 1783 by John Michell, an English country parson.

Simulacra by John Michell