Tag: old maps

• How close did Ino get? Japan’s first measured map against a modern one

  

  A retired sake brewer measured Japan on foot. I laid 28 sheets of his 1821 map on today’s coast: a typical sheet’s coast sits a median 280 m from the modern line.

  Tristan Hotham

  Data stories, Games & other interests

  coast and sea, history, old maps

• How accurate were portolan charts?

  

  I read 349 places on the Carta Pisana and the Catalan Atlas and measured them against the real coast. Both charts are turned about 11 degrees off north, the Mediterranean is drawn to within a few dozen kilometres, and beyond Gibraltar they fall apart.

  Tristan Hotham

  Data stories, Games & other interests

  coast and sea, old maps

• The Gough Map: Britain’s oldest road map, measured

  

  I found 157 towns by eye on a map of Britain drawn about 1360. Its shape puts a typical town 18 km out of place and blows Wales up, yet 72% of the miles written along its red roads are within 25% of the real road.

  Tristan Hotham

  Data stories, Games & other interests

  Britain, medieval, old maps

• The Known World

  

  A dark world that lights up as travellers wrote it down. From 681 journeys: Europe’s recorded world covered 20% of the land in 1492 and 67% in 1900, and much of the dark had been recorded by China, the Islamic world or Polynesian voyagers first.

  Tristan Hotham

  Data stories, Games & other interests

  history, old maps, world maps

• Booth’s poverty map today

  

  I read Charles Booth’s 1898 to 1899 poverty colours along every street of today’s inner London and set them against deprivation in 2025. The poorer streets of the 1890s are still slightly more deprived (rank correlation 0.20), and only very locally: slide the old map 1 km and most of the link goes.

  Tristan Hotham

  Data stories, Games & other interests

  cities, history, industry, old maps