Who’s your benchmark? ⠀
A parent?... A friend?... Oprah? We all need that someone to measure ourselves against, make sure we’re on the right track...that we’re reaching the heights we’re aiming for. ⠀
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Well... the same goes for an OS Map. These wee symbols are ACTUAL bench marks. Introduced in 1854, they are carved on buildings and bridges all around mainland Great Britain. ⠀
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Hidden in plain sight, they are usually cut into sandstone and take the form of a horizontal line with an arrow pointing up from below. ⠀
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The marks were carved by Ordnance Survey levelling staff to provide a network of points at which the height was precisely measured above sea level. The elevation was then documented and recorded on an OS map.⠀
Each one’s accuracy was trusted enough to be able to measure the next... and the next... and the next... like a game of stone carving Chinese whispers, only much more precise!⠀
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GPS has since replaced bench marks as a more accurate way of measuring elevation. ⠀
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The symbols may not serve any real purpose anymore but they are a wonderful reminder of a time when, in order to get the measure of where you are or where you are going, you needed to trust the person that had seen it, done it and made the mark before you.
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