Hedley was first and foremost a mine engineer - and an excellent one at that. His only real interest in steam locomotion was as an economical method of transporting coal from his employer's colliery to the River Tyne.
Nevertheless it was Hedley, and not George Stephenson, whose ingenuity would turn what was simply an interesting idea into a practical transport system that would sweep the world.
Hedley was born in the Tyneside village of Newburn on July 13th, 1779, and fortuitously was sent to school in the neighbouring village of Wylam.
His path to school, took him alongside the Wylam Colliery wagonway, which would eventually play such a significant role in locomotive development. At that time, the wagonway was used by horses pulling single chaldron wagons on wooden rails from the colliery to the river staithes at Lemington on Tyne, where the coal was loaded into vessels known as "keels" for onward transport.
Coincidentally, the wagonway passed in front of the cottage, High Street House, where George Stephenson was born on June 9th, 1781. The paths of the pair must have crossed many times in those early years.
Hedley trained as a colliery viewer - the man who has overall charge of the running of a coal mine - and by the tender age of 21 was appointed manager at Walbottle Colliery near his home.
Meanwhile, Christopher Blackett, owner of Wylam Colliery, had become interested in the experiments of Cornish engineer Richard Trevithick, whose primitive, five-ton locomotive had proved too heavy for the brittle rails of the Penydaren tramway in south Wales. Blackett ordered an engine to be built to Trevithick's design at the Whinfield foundry in Gateshead.
Construction began in October,1804, and the machine was ready by the following May, but it never left the works.
The reason is obscure but John Turnbull, an apprentice at Whinfield's, later recalled that when the engine was finished, a temporary way was laid down in the works "to let the quality see her run." She ran well, both backwards and forwards, but Blackett did not take her.
"There was some disagremancy between him and the master, and she never left the works, but was used in the foundry as a fixed engine, to blow the iron down."
the likelihood is that Blackett realised it would be far too heavy for the Wylam wagonway's wooden rails and pulled out of the deal.
Blackett had his wooden wagonway rails replaced by cast-iron plate rails in 1808, making life much easier for his horses, and at the same time he revived his interest in steam power. He asked Trevithick for more help but the Cornishman had lost interest in the subject and declined the invitation.
Trevithick's Penydaren engine had relied for its pulling power on simple adhesion between a smooth rail and smooth wheel treads, but the principle was far from proved in practice. Most people felt the idea would not work when a smooth-wheeled engine was asked to pull a load greater than its own weight, and it was this belief that prompted John Blenkinsop, the colliery viewer at Middleton near Leeds, to specify the rack-and-pinion drive he had patented when he asked engineer Matthew Murray to build an engine for his tramway in 1811.
Blenkinsop had two cog-wheel locos running by the summer of 1812, and although the system had obvious limitations it attracted widespread interest. Three similar engines were built for Orrell colliery, near Wigan, while John Watson, viewer of Newcastle's Kenton and Coxlodge Colliery, bought an ex-Middleton Colliery engine after converting his own pit's tramway to the rack system and began operating on September 2nd, 1813.
However, the rack-and-pinion idea did not appeal to Blackett, who had recently spent a lot of money laying his cast-iron plate rails, so in the autumn of 1812 he asked Hedley to investigate the problem.