 They strengthened the track for locomotive operation, and the Edinburgh to Carlisle route became the Waverley Route.The Edinburgh and Dalkeith line was referred to by a writer as "the Innocent Railway", referring to its unsophisticated horse traction and leisurely ways; the term was understood later to refer to the line's supposed freedom from accident, although this is not historically accurate.The city of Edinburgh had an accelerating demand for coal in the early years of the nineteenth century, rising from 200,000 tons per year in 1800 to 350,000 in 1830.