fessor Airy of course was,
having been a senior wrangler himself--knew perfectly well that the
labeling of a young man on his taking his degree is much more worthless
as a testimony to his genius and ability than the general public is apt
to suppose.

Was it likely that a young and unknown man should have solved so
extremely difficult a problem? It was altogether unlikely. Still, he
should be tested: he should be asked for explanations concerning some of
the perturbations which Professor Airy had noticed, and see whether he
could explain these also by his hypothesis. If he could, there might be
something in his theory. If he failed--well, there was an end of it. The
questions were not difficult. They concerned the error of the radius
vector. Adams could have answered them with perfect ease; but sad to
say, though a brilliant mathematician, he was not a man of business. He
did not answer Professor Airy's letter.

It may seem a pity to many that the Greenwich equatorial was not pointed
at the place, just to see whether any foreign object did happen to be in
that neighborhood; but it is no light matter to derange the work of an
observatory, and alter the plans laid out for the staff, into a sudden
sweep for a new planet on the strength of a mathematical investigation
just received by post. If observatories were conducted on these
unsystematic and spasmodic principles they would not be the calm,
accurate, satisfactory places they are.

Of course, if anyone had known that a new planet was to be found for the
looking, _any_ course would have been justified; but no one could know
this. I do not suppose that Adams himself felt an absolute confidence in
his attempted prediction. So there the matter dropped. Adams's
communication was pigeonholed, and remained in seclusion eight or nine
months.

Meanwhile, and quite independently, something of the same sort was going
on in France. A brilliant young mathematician, Urban Jean Joseph
Leverrier, born in Normandy in 1811, held the post of astronomical
professor at the Ecole Polytechnique, founded by Napoleon. His first
published papers directed attention to his wonderful powers; and the
official head of astronomy in France, the famous Arago, suggested to him
the unexplained perturbations of Uranus as a worthy object for his fresh
and well-armed vigor. At once he set to work in a thorough and
systematic way. He first considered whether the discrepancies could be
due to errors in th