Thames school of chartmakers

The Thames school of chartmakers was a small group of English nautical chartmakers who plied their trade in streets and alleys leading down to the waterfront on the north Bank of the Thames, east of the Tower of London. Active between 1590 and 1740, they were critically involved in England's maritime affairs, yet the school was not identified by modern scholars until 1959.
Further information is available in the article Joel Gascoyne, who was a prominent member.