ONE of the great unanswered questions from the early days of steam locomotion concerned George Stephenson, his childhood pal Timothy Hackworth and a faulty steam cylinder.

Both men were born in Wylam, Northumberland, and both grew up to be engineers. Hackworth (1786-1850) was, in fact, one of the earliest railway engineers, helping his boss William Hedley build the innovative 'Puffing Billy' in 1813.

So he already had a wealth of experience when he was appointed locomotive foreman of the Stephenson-built Stockton-Darlington Railway in 1825.

Hackworth was the son of John Hackworth, the foreman blacksmith at Wylam Colliery, and when he left school at 14 he began a seven-year apprenticeship, finishing his indentures in 1807 and taking over the duties of his father, who had died three years earlier.

He held the position for eight years, and it was during this spell that he helped Hedley built 'Puffing Billy.' Then he moved to Walbottle Colliery, and spent several months on secondment running Stephenson's Newcastle works. He did it so well that when Stephenson returned from a business trip, he offered Hackworth half of his own share in the company.

Hackworth said 'No', but within 12 months he had agreed to become engine superintendent on the Stephenson-built Stockton and Darlington Railway at a salary of £150 a year, all found. He was provided with a small workshop at Shildon, near the terminus of the line, and built it up so that he could manufacture engines as well as repair them.