It is most difficult to give any adequate impression of his far-reaching ability and measureless activity. Perhaps the best idea of these qualities may be obtained from a study of his autobiography, edited and published some four years after his death by his son. The book, to any one who was not personally acquainted with Airy, is heavy and monotonous, chiefly for the reason that its 400 pages are little but a mere catalogue of the works which he undertook and carried through; and catalogues, except to the specialist, are the dullest of reading. To enter into the details of his work might fill a library. [Illustration: THE ASTRONOMER ROYAL'S ROOM.] As Astronomer Royal he seems to have inherited and summed up all the great qualities of his predecessors: Flamsteed's methodical habits and unflagging industry; Halley's interest in the lunar theory; Bradley's devotion to star observation and catalogue making; Maskelyne's promptitude in publishing, and keen interest in practical navigation; Pond's refinement of observation. Nor did he allow this inheritance to be merely metaphorical; he made it an actual reality. He discussed, reduced, and published, in forms suitable for use and comparison to-day, the whole vast mass of planetary and lunar observations made at the Royal Observatory from the year 1760 to his own accession, a work of prodigious labour, but of proportionate importance. Airy has been accused--and with some reason--of being a strong, selfish, aggressive man; yet nothing can show more clearly than this great work how thoroughly he placed the fame and usefulness of the Observatory before all personal considerations. With far less labour he could have carried on a dozen investigations that would have brought him more fame than this great enterprise, the purpose of which was to render the work of his predecessors of the highest possible use. The light in which he regarded his office may best be expressed in his own words:--