Bode's law, he obtained a first approximation to the position of the
supposed planet. He then asked Professor Challis, of Cambridge, to
procure the latest observations of Uranus from Greenwich, which Airy
immediately supplied. Then the whole work was recalculated from the
beginning, with more exactness, and assuming a smaller mean distance.

In September, 1845, he handed to Challis the elements of the
hypothetical planet, its mass, and its apparent position for September
30th, 1845. On September 22nd Challis wrote to Airy explaining the
matter, and declaring his belief in Adams's capabilities. When Adams
called on him Airy was away from home, but at the end of October,
1845, he called again, and left a paper with full particulars of his
results, which had, for the most part, reduced the discrepancies to
about 1". As a matter of fact, it has since been found that the
heliocentric place of the new planet then given was correct within
about 2 degrees.

Airy wrote expressing his interest, and asked for particulars about
the radius vector. Adams did not then reply, as the answer to this
question could be seen to be satisfactory by looking at the data
already supplied. He was a most unassuming man, and would not push
himself forward. He may have felt, after all the work he had done,
that Airy's very natural inquiry showed no proportionate desire to
search for the planet. Anyway, the matter lay in embryo for nine
months.

Meanwhile, one of the ablest French astronomers, Le Verrier,
experienced in computing perturbations, was independently at work,
knowing nothing about Adams. He applied to his calculations every
possible refinement, and, considering the novelty of the problem, his