Air Brakes for Freight Trains: Technological Innovation in the American Railroad Industry, 1869–1900

The Westinghouse air brake, a significant technical innovation in the railroad industry of the late nineteenth century, was applied to freight trains much more gradually than it was to passenger trains. In this article, Mr. Usselman explains why this was the case. Many factors, including the public movement for railroad safety, the organization of railroad brakemen, the rise of effective regulatory mechanisms at the federal level, and technical problems with the device, influenced the diffusion of the air brake and differentiated the freight and passenger cases. New administrative procedures for moving freight trains through the extensive national railroad system, which involved the interchange of equipment among many companies, presented obstacles to innovation that did not exist in the passenger branch of the industry. Individual companies seeking to adopt the air brake for freight service found that these procedures limited the independence they had traditionally enjoyed when assessing new technology. Most railroads equipped their freight trains with air brakes only after they developed new methods of coordinating industrywide action on matters of technological change.