Opening Day at Broad Branch Road, 1914

Opening day at BBR
Wednesday, April 09, 2014 

“Perhaps no building being erected at the present time has excited so much interest … as has the new edifice in progress [at Broad Branch Road].  Certainly no structure has required so much precise care in workmanship and a thorough knowledge of building to meet the delicate needs of a building of this character.  It is the last word in scientific building.”

Washington TimesNovember 22, 1913

April 1, 1914 was cool and rainy, but spirits must have been high among the scientists and staff of the Department of Terrestrial Magnetism.  After ten years quartered in rented rooms in the Ontario Apartment House near the National Zoo, the Department marked the start of its eleventh year on its own new campus “out in the country” on Washington’s northwest fringe.

DTM’s expanding program of experimental research and the need for fireproof storage for its precious archive of geophysical data had convinced the Carnegie Institution’s Trustees in 1913 to allocate $127,200 – $3 million in today’s dollars  –  to build it a permanent home.  A seven-acre tract “admirably located amidst rural surroundings” near Rock Creek Park was acquired, sufficiently far from “disturbing influences” (such as electric street-car lines) for the Department’s precise scientific measurements.

Waddy B. Wood, a prominent Washington architect, was selected to design the new laboratory and office building. Requirements drawn up by DTM director Louis A. Bauer and his chief assistant (and successor), John A. Fleming guided him in his task.  Bauer and Fleming had scrutinized the plans of a dozen recently-completed physical laboratories and Wood was himself no stranger to designing research buildings.  Just seven years earlier he had designed the Geophysical Laboratory’s headquarters, situated a mile to the south.   But the particular requirements for DTM’s new home posed special challenges.  Not only did the building need to be exceptionally strong and fireproof, but its floors and walls had to be “vibrationless.”  Ironically, for an organization founded by a steel magnate, the use of structural steel had to be kept to a minimum to reduce magnetic interference. 

Clearing land at Broad Branch Road, 1913.

The challenge of realizing the new structure fell to the Davis Construction Company, which broke ground in May, 1913.  Working primarily in reinforced concrete and brick, the builders employed novel and sometimes difficult construction techniques, in particular, isolating the massive floor slabs from the walls by beds of sand.  Local papers followed the unusual and complex project.   “Science Structure Hard on Builders” reported the Washington Times in September, 1913.  “There is certainly no other structure in this city which requires the care in building that compares with it, and it is the general belief that there is nothing exactly similar in the country.”

On February 14, 1914 the elegant, brick Italian Renaissance-style “Main Building” was finished.  It had cost $68,000 to build – in an era when the average American earned $600 a year and a typical home cost $3,000.  Underground were constant-temperature rooms for experiments; above, three floors of offices, laboratories, computing rooms (“computers” were human then), an instrument shop, library and archives.  A rooftop deck for observational work crowned the building.   The latest utilities were provided throughout:  alternating current, direct current from a central storage-battery room, gas, water, and a 14-telephone network.  A symbolic compass rose cast in brass and set in the vestibule floor branded the building for its intended mission in geomagnetic research. 

Written by Shaun Hardy


The Carnegie Institution celebrates a century of science and discovery at its Washington, DC, campus this month. Learn about our campus history and join us at one of our events in commemeration of our centennial.

Postscript.  Eight decades later, overcrowded and showing its age, the old Main Building was surpassed by a new structure as the dominant building on campus - the state-of the-art “Research Building for the Earth and Planetary Sciences.”   In 1990, the Geophysical Laboratory moved from its historic home on Upton Street, NW to share the Broad Branch Road campus with DTM.  The Main Building was gutted and completely renovated to serve a new role as the administrative hub of a now much-enlarged scientific community.  In addition to housing the headquarters of both DTM and GL, the Main Building holds the campus library and archives, as it has since 1914.  In 1999, it was renamed the “Abelson Building” in honor of Philip H. Abelson, a former DTM staff scientist, Geophysical Laboratory director, and Carnegie Institution president.