William Yolland CB, FRS FRSA (17 March 1810 – 4 September 1885) was an English military surveyor, astronomer and engineer, and was Britain's Chief Inspector of Railways from 1877 until his death. He was a redoubtable campaigner for railway safety, often in the face of strong opposition, at a time when railway investment was being directed towards the expansion of the networks rather than the prevention of accidents. He was a member of the three-man committee of inquiry into the Tay Bridge disaster. Career Yolland was born in Plympton St Mary, Devon, the son of the land agent to Lord Morley, Plymouth, and his father promoted the boy's interest in surveying and land management by enrolling him at a school specialising in mathematics. He was commissioned into the Royal Engineers in 1828 and completed his technical training at the Royal School of Military Engineering in Chatham, Kent, in 1831. Ordnance Survey After army service in Britain, Ireland and Canada he was posted to the Ordnance Survey in 1838. He made a strong impression there, particularly with his mathematical knowledge and publications on astronomy, and in 1846 he was nominated to head the organisation by its departing Superintendent, General Thomas Colby. He was, however, thought too young for the post and an older officer (a sapper who had no survey experience) was appointed instead. This new Superintendent, Colonel Lewis Hall, despatched Yolland back to Ireland to avoid his embarrassment in commanding a more qualified officer, but the survey there was of greater importance than Hall had realised: Parliament had noticed that revenue was being lost as land assessments for tax were not up to date and Yolland's progress there was followed with interest. In 1849, he was called to appear before a parliamentary select committee to explain how his method of mapping settlements in Ireland could be applied in England, as more detailed town maps were urgently needed to assist in the planned reforms of town sanitation. The interest in Yolland's work in Ireland survives to this day: as a young man he appears as a leading character in Brian Friel's play Translations, a modern play set in nineteenth century Co. Donegal. The character of Yolland in Translations is fictionalised, however, as he is called George Yolland and is missing, possibly dead, at the play's end. General Colby appears as "Captain Lancey". Yolland's technical account of establishing a triangulation base near