English: A rare and remarkable discovery this is Joseph Tiefenthaler and Anquetil-Duperron’s important 1784 map of the Ganges and Ghaghara (Karnali) river system. As a whole this map is a significant advancement over earlier mappings of this region as evidenced in the works of De L’Isle and others. Presented here are actually six maps on a single sheet. The central map (Fig. 1), showing the entire course of the Ganges and the Ghaghara rivers, is a European style map produced by Tiefenthaler based upon his own travels and quadrant surveys as well as on the indigenous cartography he collected along the way. Four of the five smaller maps presented are in fact Tiefenthaler’s copies of Indian maps given to or provided for him. The stylistic difference between these and the central European style map are clear, especially as regarding the rendering of direction, bodies of water, and topography. Tiefenthaler’s copies of indian cartographic material include figures II, III, IV, and V. Figure II correctly locates the source of the Ganges at the Gangotri Glacier, Gaumukah, known as the “Cow’s Mouth” due to its strong resemblance to the open mouth of a cow. Figure III, a large map at the top center, focuses on the Lake of Mansarovar (Mansaroar), the supposed source of the Karnali or Ghaghara River. It is unlikely that Tiefenthaler actually ever say Mansarovar as this lake is located high on the Tibetan Plateau which, during this historic period, was closed to foreigners. Figure IV is another Indian chart focusing on the secondary sources around the volcano of Doulou Bassandar. Figure V shows a secondary source for the Ghaghara as it runs through the Himalayas. Figure VI depicts earlier misconceptions regarding the source of the Ganges as suggested by P. Souciet in his 1729 four volume work Observations, Mathematical, Astronomical, Geographica, Chronological, and Physical . One of the most striking elements of this map is the inclusion of Pesian text in each of the maps Tiefenthaler claims to have copied from indigenous sources. These text blocks are vaguely transliterated and translated into French in a table in the upper left quadrant. The is the only European map of India we are aware of to incorporate Persian text. Most of the cartographic work that led to this map was completed by Tiefenthaler in India. Tiefenthaler, near the end of his life, forwarded it to his friend and fellow orientalist Anquetil-Duperron, living at the time in Paris. Duperron, a noted orientalist, compiled Tiefenthaler’s research and sketches into this important independently issued map. Though significant in its time this map is little known by modern cartographic historians who, when discussing the mapping of India, tend to focus on the later work of Rennell.