In 1798, James Rennell, an English cartographer primarily known for his maps of British territories in India and South Asia, published A map shewing the progress of discovery & improvement, in the geography of North Africa. This map combined geographical information gathered from sources spanning more than 1.5 millennia, from recent explorers all the way back to Claudius Ptolemy, who wrote his Geographia in approximately 150 CE.
Rennell’s map was compiled primarily from the reports of two Scottish explorers, James Bruce and Mungo Park, who had traveled in Ethiopia and West Africa (respectively) in the later decades of the 18th century. Rennell frequently credits his sources for individual place names; in addition to Ptolemy, Bruce, and Park, the French cartographer Jean-Baptiste Bourguignon d’Anville and the Mamluk geographer Abu’l-Fida are both cited.
Rennell followed a tradition, begun by d’Anville earlier in the 18th century, of leaving large blank spaces where the state of contemporary European knowledge remained ignorant. In previous centuries these areas, particularly in Africa, had often been populated by various fantastic beasts and peoples – think cannibals, dog-headed people, and my personal favorites, the sciapods, who had one single foot which was so large it could be used to shade oneself from the sun. Now, the sciapods were no more: Enlightenment-era science reigned, and the observations of European explorers took precedent over conjecture – but not always over the Ancients.
Let’s examine some of the places which appear on this map, and see how Rennell united Enlightenment observational data with the ancient geographical bequest of Ptolemy.
The map’s coverage begins a few degrees south of the equator, although geographical information aside from coastal topography and toponyms is sparse below about 10 degrees north. In the southeast, the first place name to appear on the map – indeed, nearly off the edge of it – is “Melinda” (Malindi). One of the great Swahili trading cities which played host to African, Arab, Persian, Chinese, and Portuguese merchants for several hundred years, Malindi was in decline in the late 18th century, having been eclipsed in importance by Mombasa. The toponym “Zanguebar” refers to the Sultanate of Zanzibar, a part of the Omani Empire ruled from Muscat via the island of Zanzibar (itself too far south to appear on the map).
Heading north along the Indian Ocean coast, we pass “Azania,” the first Ptolemaic place name, and then eventually reach Cape Guardafui – old Italian for “look and escape,” referring to the dangerous passage around the coast.
Much richer detail is to be found in Abyssinia, where we pick up the trail of James Bruce, the first of our Scottish explorers, indicated by a double line of dots. He passed through the city of Gondar – the Ethiopian capital since the 17th century – and traced the route of the Blue Nile, marked by Rennell as “Bahr Azrac or Blue River.”
Other parts of Rennell’s map reflect the European obsession with finding the ultimate source of the Nile. Just west of Abyssinia, some dubious tributaries appear, originating in the legendary Mountains of the Moon. Here Rennell makes sure to state that his information comes from “Ptolemy and the Arabian Geographers.”
Once it joins up with the Blue Nile, the Nile’s course is much less dubious. It passes through a string of towns, cities, deserts, and cataracts until it reaches Cairo, from where the “Road of the Pilgrims to Mecca” sets off to the Arabian Peninsula.
Rather than depicting the Sahara as a featureless expanse of sand (which, in fact, it is not), Rennell shows the great desert as a busy place, criss-crossed by trade routes which connect cities and oasis towns such as Mourzouk (Murzuk), Gadamis (Ghadames), and Agades (Agadez). The region of “Bornou, or Kanem” (the Kanem-Bornu Empire) contains several cities, but seemingly not the 15th-century walled capital of Ngazargamu, which would be sacked in one of the Fulani jihads a mere 10 years after this map was made.
Moving north, we arrive at the Mediterranean coast of North Africa – mostly labeled here as “Barbary” – where several provinces of the Ottoman Empire existed as de facto independent states. Tripoli, Tunis, and Algiers, along with the Sultanate of Morocco, had long been host to hotbeds of pirate activity in the Mediterranean, but this was in decline by the late 18th century when this map was made. To the west of Morocco lie the Canary Islands, where enslaved Africans farmed sugar plantations for the Spanish crown, and where a year earlier Horatio Nelson lost an arm in the Battle of Tenerife.
At the mouth of the Gambia River, we meet our second Scottish explorer, Mungo Park, whose travels in the Sahel failed to settle another of European cartographers’ longstanding confusions about African hydrography: the course of the Niger River. Park reached the banks of the Niger shortly downstream from its source, here in the Mountains of Kong (near the region labeled “Manding”), in actuality the Guinea Highlands. He followed the river past the Bamana imperial capital of Sego (Ségou), and this region of the map is rich in detail and place names. However, Park turned back before reaching Tombuctoo (Timbuktu), and he never learned where the river entered the sea.
Lacking knowledge of its dramatic sweep toward the south past Timbuktu, Rennell depicts the Niger River as flowing east, along the southern edge of the Sahara, past the Hausa city-state of Kassina (Katsina) and into a lake, Lybia Palus, just west of Kanem-Bornu. Here it meets up with a Ptolemaic series of lakes and rivers, one of which very nearly joins up with the Nile.
Returning west to the large region labeled “Guinea,” we see that data in this part of the map stops a few miles inland from the coast. While this area was well-known to Europeans involved in trading both goods and captives, European activity was generally limited to ports and coastal forts. Just south of the cities of Benin and Waree (Warri), the tangle of small, undifferentiated river mouths around Cape Formosa is in fact the complex delta of the great Niger River. After turning south at Timbuktu, if Rennell’s map were accurate, the river would have encountered a major obstacle in the form of the Mountains of Kong. However, fortunately for the river – and unfortunately for the contemporary state of English geography – there are no Mountains of Kong, and the river flows unimpeded into the Gulf of Guinea.