The middle of the eighteenth-century marked the end of the secrecy policy of the VOC. From 1743 to the dissolution of the company in 1799, three generations of mapmakers from the Van Keulen family held the office of mapmaker of the VOC in Amsterdam. Like the Blaeu’s the Van Keulen’s were commercial publishers as well. Johannes II van Keulen was the first mapmaker who was given permission to publish a pilot guide for the Asian waters. This volume saw the light in 1753 as the sixth volume of De Nieuwe Groote Lichtende Zee-Fakkel. This volume contains two maps that include the Vietnamese coasts, based on earlier manuscript VOC charts. One chart shows the coasts around the southern part of the South China Sea, including the southern coasts of Vietnam. The other, on a slightly larger scale, shows the coasts from Hội An (misspelled as ‘Taisoe’) to Canton (Guangzhou), including the Gulf of Tonkin.
Jan de Marre, [Kaarten in De nieuwe groote lichtende zee-fakkel. Sesde deel]. Amsterdam: Johannes van Keulen, 1753 (KITLV M x 603)