Airy seems to have had a strong bent in the direction of astronomy
from his youth, and it is curious to note how well furnished he was,
by the time that he became Astronomer Royal, both with astronomy in
all its branches, and with the kindred sciences so necessary for the
practical working and improvement of it. At the time that he went to
Cambridge Physical Astronomy was greatly studied there and formed a
most important part of the University course. He eagerly availed
himself of this, and mastered the Physical Astronomy in the most
thorough manner, as was evidenced by his Papers collected in his
"Mathematical Tracts," his investigation of the Long Inequality of the
Earth and Venus, and many other works. As Plumian Professor he had
charge of the small Observatory at Cambridge, where he did a great
deal of the observing and reduction work himself, and became
thoroughly versed in the practical working of an Observatory. The
result of this was immediately seen in the improved methods which he
introduced at Greenwich, and which were speedily imitated at other
Observatories. Optics and the Undulatory Theory of Light had been very
favourite subjects with him, and he had written and lectured
frequently upon them. In the construction of the new and powerful
telescopes and other optical instruments required from time to time
this knowledge was very essential, for in its instrumental equipment
the Greenwich Observatory was entirely remodelled during his tenure of
office. And in many of the matters referred to him, as for instance
that of the Lighthouses, a thorough knowledge of Optics was most
valuable. He had made a great study of the theory and construction of
clocks, and this knowledge was invaluable to him at Greenwich in the
establishment of new and more accurate astronomical clocks, and
especially in the improvement of chronometers. He had carefully
studied the theory of pendulums, and had learned how to use them in
his experiments in the Cornish mines. This knowledge he afterwards