You are absolutely correct the first detailed maps of Great Briatain were for military use 1. History of maps since the Royal Board of Ordnance first surveyed ... From revolution to e-volution: a short history of Ordnance Survey. www.ordnancesurvey.co.uk/aboutus/history/index.html - ordinance survey history >> Revolution! England was squeezed between rebellion in Scotland and war with France when King George II commissioned a military survey of the Scottish highlands in 1746. The job fell to William Roy, a far-sighted young engineer who understood the strategic importance of accurate maps. Walk into Ordnance Survey's Southampton head office and you'll see Roy's name engraved on the curved glass entrance doors, yet his vision of a national military survey wasn't implemented until after his death in 1790. By then Europe was in turmoil, and there were real fears that the French Revolution might sweep across the English Channel. Realising the danger, the government ordered its defence ministry – the Board of Ordnance – to begin a survey of England's vulnerable southern coasts. Military mapping 'Plan of the triangles', connecting the meridians of Greenwich and ParisIn June 1791, the Board purchased a huge new Ramsden theodolite, Ramsden Theodoliteand surveyors began mapping southern Britain from a baseline that Roy himself had measured several years earlier. The first one-inch map of Kent was published in 1801, and a similar map of Essex followed – just as Nelson's victory at Trafalgar made invasion less likely! Lough FoyleWithin twenty years about a third of England and Wales hadThomas Colby been mapped at the one-inch scale. If that seems slow in these days of aerial surveys and global positioning, spare a thought for Major Thomas Colby – later Ordnance Survey's longest serving Director General – who walked 586 miles in 22 days on a reconnaissance in 1819. A taxing business In 1824, Parliament ordered Colby and most of his staff to Ireland, to produce a detailed six inch to the mile valuation survey. Building trig pillarsColby designed specialist measuring equipment, established systematic collection of place names, and reorganised the map-making process to produce clear, accurate plans. But Colby the perfectionist also travelled with his men, helped to build camps, and arranged mountain-top feasts with huge plum puddings at the end of each surveying season. Soon after the first Irish maps began to appear in the mid-1830s, the demands of the Tithe Commutation Act provoked calls for similar six-inch surveys in England and Wales. The government prevaricated but, by then, there was a new power in the land. Driven by steam This was the era of railway mania and if the one-inch map was unsuitable for calculating tithes, it was virtually useless for the new breed of railway engineers. To make matters worse, mapping of England and Scotland remained incomplete and, in 1840, the Treasury agreed that the remaining areas should be surveyed at the six-inch scale. Now, surveyors needed greater access than ever before; and so, in 1841, the Ordnance Survey Act gave them a legal right to 'enter into and upon any land' for survey purposes. . . . . << lots more http://www.google.com/search?hl=en&q=ordinance+survey+history&btnG=Google+Search&aq=f&oq= and today http://www.ordnancesurvey.co.uk/oswebsite/ Hugh W [email protected] wrote: > Dennis, > > This may seem like a funny question, but what exactly is an ordnance map? I have looked at them, but cannot figure out why they are called that. As an old Marine, my mind tends to lean toward ammunition, although, I am aware that is ordinance. Another meaning would be a law - as a city ordinance. So what is an ordnance map? > > Bill Karr > > -------------- Original message -------------- > From: Dennis Ahern <[email protected]> > >> The most important point that people seem to be missing is that the >> Ordnance Survey maps do not have the identifying keys that match the >> reference column on the published pages of Griffith's Valuation. As far as >> I know, the only maps that have those keys are the ones available at the >> Valuation Office in Dublin. The only thing that is identified on the OS >> maps are the townlands themselves, which narrows things down, but you >> still have no way of knowing which "house" is the one you are trying to >> locate on the map. The version on the askaboutireland website gives a >> different number from what is in the published Griffith's. My problem is, >> I cannot find this point on their map. >> >> -dja >> >> >> ------------------------------- >> To unsubscribe from the list, please send an email to >> [email protected] with the word 'unsubscribe' without the quotes in >> the subject and the body of the message