Cool Passengers on the B&O

On April 23, 1930, the B&O Railroad debuted a new richly appointed dining car named Martha Washington. One of its series of “Colonial” diners, this heavyweight car was adorned with shield back mahogany chairs, fancy architectural details, and crystal lighting. Its menus were branded as “tavern fare” and featured specialties of Chesapeake regional cuisine not unlike our forefathers would have known in colonial times. The Martha Washington, however, had a feature that no other passenger car in the world had ever had before; air conditioning!

Interior of the B&O "Colonial" dining car "Martha Washington". The world's first air conditioned railroad car, 1930.

During the preceding two years, B&O mechanical and electrical engineers spent many sequestered dark days in a tin sided wooden shed appended to the rear of the Mt. Clare Roundhouse with an inventor and engineer named Willis Haviland Carrier and his team to design and install a system of passenger car air conditioning that would, one day, serve the world of trains.

Mt. Clare Air Conditioning Test Shed 1934

Carrier was born in New York in 1875 and graduated with an engineering degree from Cornell in 1901. A 1902 Ripley’s “Believe It Or Not” article titled “While Walking in a Fog” detailed Carrier’s inspiration to invent air conditioning while waiting for a train in Pittsburgh amidst a dense fog. His first patent was in 1906 and he successfully air conditioned the first building in America in Minneapolis in 1914.

Willis Haviland Carrier, the father of modern air conditioning

Much secrecy surrounded the development of railroad car air conditioning at Mt. Clare. Once designed and installed in the prototype diner hidden away in the little test shed, B&O engineers heated the interior of the car to a temperature of 93 degrees, turned off the heat and then turned on the newly installed air conditioning to test it capabilities. On the first attempt, the interior of the car reached 73 degrees in 19 minutes and 30 seconds.

Successfully launched and another “first” in the long line of B&O Railroad’s legendary innovations, the B&O went about applying Carrier’s adapted invention to an entire train. On May 24, 1934 the B&O inaugurated the World’s first fully air conditioned train The Columbian for its maiden run from Washington D.C. to New York.

Courtney B. Wilson
Executive Director