Swift's attempts to sell Chase's design to major railroads were rebuffed, as the companies feared that they would jeopardize their considerable investments in stock cars, animal pens, and feedlots if refrigerated meat transport gained wide acceptance. In response, Swift financed the initial production run on his own, then — when the American roads refused his business — he contracted with the GTR (a railroad that derived little income from transporting live cattle) to haul the cars into Michigan and then eastward through Canada. In 1880 the Peninsular Car Company (subsequently purchased by ACF) delivered the first of these units to Swift, and the Swift Refrigerator Line (SRL) was created. Within a year, the Line's roster had risen to nearly 200 units, and Swift was transporting an average of 3,000 carcasses a week to Boston, Massachusetts. Competing firms such as Armour and Company quickly followed suit. By 1920, the SRL owned and operated 7,000 of the ice-cooled rail cars. The General American Transportation Corporation would assume ownership of the line in 1930.