His career was detailed in a book by John Ware (revised and completed by Robert R. Rea) entitled "George Gauld, Surveyor and Cartographer of the Gulf Coast" published by the University of Florida press.
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Above is a Gauld map of the Mississippi River and Lake Pontchartrain as published in 1803. Note that the land lying between the Mississippi River and the Amite River was thought to be an island.
Gauld created a number of coastal maps for the British Royal Navy, and some of them were instrumental in convincing incoming settlers to visit the north shore of Lake Pontchartrain.