As the Harvard College Observatory prepares for its centennial celebration on December 27, its staff scarcely glances back over the arduous way travelled since that meagre beginning in 1846, when the first permanent observation station was founded: a ten-room building on Summer House Hill, equipped only with a 15-inch refractor and meridian circle determinants of time and star positons.

Eyes are turned skyward to the future, which all co-workers, in this clearing house for astronomical data in the Western Hemisphere, feel should shortly see "an enriched knowledge of our earth's gaseous envelope, a reasonable interpretation of the origin of meteors and comets, and the cosmic significance of the dusty clouds of interstellar space."

While the 15-inch refractor remains, though merely as a monument to the past, the meridian circle equipment has long gathered dust in an obscure store-room. In the meantime, astronomic investigation at the University, with the Summer House Hill establishment as control center, has assumed Herculean proportions, its activities diversified, its observation posts so scattered over the face of the earth that it may truly be said, "The stars never shine without the eye of Harvard upon them."

Station Born of Comet. . .

Astronomy actually got its start at the University in 1839, when William C. Bond, later to become first director of the Observatory, organized a star-gazers' club, meeting bi-monthly in Dana House. Interest, however, waned, and the club was on the point of dissolution when, in March, 1843, a brilliant comet saved the day for astronomy at Harvard.

Streaking across the afternoon sky, this comet brought astronomers from all corners of the nation to Cambridge, where, it was rumored, existed an observation station. Disappointment was great upon discovery of University astronomers peering skyward with hand-shielded but naked eye, just as the visitors had already done.

Interest was aroused, however, and individual as well as society financial support finally warranted purchase of a refractor with a 15-inch aperture. The lens arrived at Cambridge in December, 1846, was erected in a 30-feet dome, and thus the College Observatory was born. Obsolete as this ancient refractor now seems, it was instrumental in bringing the Observatory to the world's attention with the discovery of the eighth and ninth satellites of Saturn.

"From this small beginning, big tough it appeared at the time, the Observatory has grown to one of the largest research institutions in the world," says Charles A. Federer, Jr., Editor of the Observatory's monthly magazine, Sky and Telescope. The old refractor and meridan circle apparatus have been replaced long ago by more than 30 separate instruments, varied in design and highly specialized in function.

Since Harlow Shapley, Paine Professor of Practical Astronomy and world-renowned expert on external galazies--those outside the Milky Way, assumed the duties of director of the Observatory in 1921, the organization has expanded many times over necessitating recently joint directorship. Bart J. Bok, associate professor of Astronomy now serves as the Observatory's associate director under Professor Shapely and Donald II. Mcnzel, professor of astrophysics, has been appointed director for solar research.

Shapely, who instituted the first graduate School of Astronomy in this country shortly after taking office, ahs watched his trust grow from a small Summer House Hill station and a run-down observation post at Arequipa, Peru, to a vast net-work of the most modernly equipped outposts, situated for complete, continuous observation of all the heavens, and planned to cover the many divergent phases of modern Astronomy.

1927 saw the expensive piece-meal movement of a greatly improved Boyden station from Peru to the climatically far superior terrain in the high veldt of Orange Free State, South Africa. Here six telescopes are in constant use, systematically photographing the Southern skies.

The resultant plates are forwarded to Cambridge to compliment photographic observations of the Northern Hemisphere. Thousands of these plates, stored up at Boyden station during the war, are now pouring into Cambridge.

To house these photographs, which now comprise a 500,000-plate history of the heavens for the last half-century, the fire-proof Astrophysical building was established in Cambridge in 1931. This pictorial library, largest of its kind in the world, has proved an invaluable aid in plotting the future courses of celestial bodies.

Oak Ridge Founded. . .

In 1932, the Oak Ridge Observatory, 25 miles North-east of Cambridge in Harvard Township, was established as a more likely site for the systematic photography of the Northern skies. Today, armed with a Schmidt Camera--advantages; better image over larger field, astronomically speaking short (one half hour) exposures, revealing stars down to nineteenth magnitude--the staff at Oak Ridge is aiming at a complete analysis of the Milky Way.

Newest of the college Observatory's outposts is the Solar Station at Climax, Colorado, operated, since 1940, under the joint auspices of the Observatory and the University of Colorado. Equipped with the first Lyot coronagraph in the Western Hemisphere, an instrument which enables astronomers to observe the corona of the sun without waiting for an eclipse, the Climax station is situated at an elevation of 11,520 feet above sea level, a higher altitude than that at which fliers are advised to use oxygen.

Officials in War Effort. . .

In 1942, the College Observatory staff went to war practically on mass. The highly diversified are of modern war-face had great need of their specialized talents; and while the Observatory found itself almost deserted, they helped out-race enemy scientists in the perfection of such technical, but still immensely vital, devices as Loran and aerial photography.

Amatenrs, long encouraged by College Observatory officialdom, also found themselves in great demand in war activities, especially in the fabrication work on optical parts. Also, every key man in Barker's Observatory Optical Project was originally an amateur telescope maker.

With the war ended, the Observatory, besides sponsoring two College amateur groups, the Bond astronomical club and the telescope Makers of Boston, again assumes its full role as clearing-house for all amateur and professional astronomic information in the Western Hemisphere.

In addition to these varied activities, the Observatory still finds time to serve as head-quarters for the American Association of Variable Star Observers, an organization of amateurs who have turned in more than a million reports since the Association's beginning in 1911, and to publish monthly its magazine. Sky and Telescope, for $500, mainly amateur, world-wide subscribers.

When the American Astronomic Society and the American Association for Advancement of Science convene at Cambridge two weeks hence, they will be toasting much more than 100 years of survival. They will be honoring an institution which has led the world through the tortuous paths of astronomic investigation.