Air-line railroad

An air-line railroad was a railroad that was relatively flat and straight, choosing a shorter route over an easier route. In their heyday, which was prior to aviation, they were often referred to simply as "air lines." For example, a 1903 novel indicates a character's success by noting his position as "superintendent of passenger traffic of the New York and Chicago Air Line," a fictitious railroad.

Webster's 1913 dictionary gives the definition "Air line, a straight line; a bee line. Hence Air-line, adj.; as, air-line road." (As of 2005^[update] this meaning has fallen into disuse.)

Air line railroads began to be built in the mid-nineteenth century; in 1853 the New York Daily Times ran a satirical article mocking the trend, suggesting that it was glamorous new technology and that the glamour was being used to float dubious investments:

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