The Dawning 145

In 1895, Barnard joined the Yerkes Observatory of the University of Chicago as a professor of practical astronomy. The astronomical journals fortunately contain much information on the life of Barnard and of the instruments he used. He was awarded the Gold Medal of the Royal Astronomical Society in 1897, for "his discovery of the fifth satellite of Jupiter, his celestial photographs and other astronomical works" as elucidated in the address by President of the Royal Astronomical Society, A.A. Common. "With one notable exception (that of the Sun) every description of celestial object has come under his [Barnard's] scrutiny, and his skill as an observer is only equaled by his skill as a photographer" noted Common, who continued:

The astronomical photographs which Professor Barnard has made ... with the "Willard" lens of the Lick Observatory ... are the first photographs made to show the structure of the Milky Way ... we must certainly admire, not merely the skill, but the courage ofa man who could, under the very shadow of the 36-inch refractor, demonstrate the merit of a lens which could be bought for a few shillings.

How sobering that the very structure of our Milky Way Galaxy was revealed by a 6-inch portrait lens costing "a few shillings."

The greatest photographic legacy of Barnard was his magnum opus: A Photographic Atlas of Selected Regions of the Milky Way.

To capture the Milky Way in all its glory, Edward Barnard used the Bruce photographic telescope of the Yerkes Observatory, Chicago. Finance for the telescope had been given to the University of Chicago by Miss Catherine W. Bruce. The Bruce telescope actually consisted of three individual tubes bound rigidly on the same mounting: two photographic telescopes of 10-inch and 6%-inch aperture, and a 5-inch aperture visual telescope used for tracking (guiding) of the stars as the Earth rotates. The great importance of the photographic telescopes lay in their wide-field coverage; the 10-inch had a 50-inch focal length and, to quote Barnard, gave "exquisite definition" over a field of about 7 degrees (or 14 full Shrouds of the Night moons). The plate-holder for the 10-inch carried glass negatives 12 inches square, while that

146 for the 6%-inch carried glass plates measuring 8 x 10 inches.

The scale of the photographs secured with the 10-inch was exceptionally well adapted to revealing the structure of the Milky Way; every inch covered just over one degree of sky. George Ellery Hale, director of the Mount Wilson Solar Observatory owned by the Carnegie Institute of Washington, invited Barnard to Mount Wilson in 1905. A generous grant from Mr. J.D. Hooker of Los Angeles allowed Barnard to transport the Bruce telescope to the Mount Wilson site. Barnard secured forty of his fifty photographs for his Atlas, from one of the world's premier observing sites, in a period spanning February to September, 1905. A photograph of the senior Barnard is seen in Figure 78. He died at age 65, in 1923, four years before the Atlas saw the light of day. It was published in 1927 by the Carnegie Institute of Washington (as Carnegie Publication number 247).

The Atlas was completed by Edwin Frost, Director of the Yerkes Observatory in Chicago, and by Barnard's niece, Mary Calvert. Barnard had, however, personally examined 35 700 photographic prints to select only the best to feature in his Atlas, of which seven hundred were produced. The two volume Barnard Atlas is today an exceedingly rare jewel and very highly priced on the retail market (on those rare occasions when it becomes available, usually for auction).

It takes an observer of the utmost skill to visually track an exposure for over eight hours; Barnard exposed his negative of a region in the constellations of Scorpio and Libra for an astonishing 8 hours and 40 minutes, on April 29/30, 1905. Exposure times ranged from 50 minutes to nearly 8% hours; approximately sixty percent of the Atlas photographs were exposed for 4 hours or longer. Figures 79-96 allow the reader to personally examine a selection of these riveting photographs of our Galaxy, which leave the observer spellbound. Dusty Shrouds of the Night are everywhere.

In examining these photographs, one is repeatedly reminded of the "trailing garments" and "haunted chambers" in the poem "Hymn to the Night" by Henry Longfellow:

I heard the trailing garments of the Night Sweep through her marble halls! I saw her sable skirts all fringed with light From the celestial walls!

The Dawning

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