This chapter throws new light on Petermann's coloured foldout map (see foldout map) and the progress made in discovering the geography of this Bahr el-Ghazal region that Europeans were so eager to explore. The two maps indicated in the title above refer to two editions of the same map. Both maps indicate the route that the Tinne-Heuglin expedition took in 1863, but the route discovered by the explorer Piaggia was omitted by Petermann, the publisher, and by Heuglin, the author. A poignant detail, because the Italian Carlo Piaggia, a friend and competitor who had also been invited to join the Tinne-Heuglin expedition, succeeded in 1863 in doing what Heuglin desperately wanted to accomplish: to enter the Azande country. The story behind these two maps tells us much about the underlying competition that began to develop among European nations in the discovery of this part of Africa.
Orazio Antinori's account
The large foldout maps that are attached to Heuglin's publications of 1865 (‘die Tinne’ische Expedition…’) and 1869 (Reise in das Gebiet des Weissen Nil…) are a good example of Petermann's fine cartography. Exquisitely drawn by Bruno Hassenstein, Petermann's mapmaker, it may be qualified as one of the finest maps to have been published in the Mittheilungen since the magazine's start in 1855. All the details of locations with their names and routes followed by explorers have been rendered as clearly as possible and with painstaking precision; its layout and colours reveal a considerable decorative quality.
When Heuglin drafted his map of the Western basin of the White Nile, only a few maps of that part of the region had been published. In March 1862, a map of the Bahr el-Ghazal by Guillaume Lejean appeared in Nouvelles Annales des Voyages, which was a result of his journey in February-April 1861. This map, together with those of the brothers Poncet and Petherick, provided much new information. In Petermann's Geographische Mittheilungen, part of Lejean's account was included, although this was not accompanied by the map. Strangely, in his accounts Heuglin does not refer to Lejean's map. Of the maps that had been published previously, he only mentions the one drawn by Petherick in 1861.