"Straight as a plumb line": Seaboard Air Line Railway advertisement illustrating the "quickest train service via the shortest route" to Florida, 1902."The straight line of your palm is not straighter than the straight line to the palms": another advertisement for the Seaboard Air Line's "shortest, quickest route to Florida", 1908.
An air-line railroad was a railroad that was relatively straight, following a shorter (and thus, presumably quicker) route instead of a longer, winding route. In their heyday, which was prior to aviation, they were often referred to simply as "air lines".
Dictionary definition
Webster's 1913 dictionary gives the definition "Air line, a straight line; a bee line. Hence Air-line, adj.; as, air-line road."
Public reaction
Air line railroads began to be built in the mid-nineteenth century. As early as 1853, the New York Daily Times ran a satirical article mocking the trend, suggesting that the fad for an "air line" name was being used to float dubious investments:
The "air-line" is three miles and nine-thirteenths shorter from Quattlebum to Squashtown than the present traveled route by the Conger Creek railroad.... Though we know there is already a railroad in operation between Quattlebum and Squash Town, parallel with and not far from our air-line... we feel satisfied that the immense current of travel, now passing by Conger Creek, must be changed, in the twinkling of an eye, to the air-line road. What sane individual, starting at Quattlebum and bound for Squash, will take the Conger Creek road when he can go by way of Shootsburg in two minutes less time, and at very little more cost?[1]
When actual air travel began in the United States, the older usage of the phrase "air line" led to confusion. During a spate of interest in aviation shares on Wall Street following Charles A. Lindbergh's trans-Atlantic flight in 1927, Seaboard Air Line shares actually attracted some investor curiosity because of the name's aviation-related connotations; only after noticing that Seaboard Air Line was actually a railroad did investors lose interest.[2]
Long Island Railroad, formerly a subsidiary of the Pennsylvania Railroad; especially the Ronkonkoma and Babylon Branches; track routes established before the suburban development of Long Island
Louisville, New Albany and St. Louis Air-Line Railway, part of the Southern Railway
Macon and Florida Air Line Railroad, part of the Southern Railway
^Lynch, Peter E. (2005). New Haven Railroad passenger trains. St. Paul, Minnesota: MBI Publishing Company. p. 111. ISBN978-0-7603-2288-8
^Henry, Apthorp (1886). Annual Report of the Commissioner Railroads and Telegraphs to the Governor of the State of Ohio, for the Year 1886. Hathi Trust: The Westbote Co. p. 465.
