1747 Basire Map and Chart of Sierra Leone

This is a c. 1747 map and chart of the coast of Sierra Leone most likely engraved by Isaac Basire for John Green's A New General Collection of Voyages and Travels, published between 1745 and 1747. Made during the height of the Transatlantic Slave Trade, this map depicts the major source of slaves bound for the British colonies in America.

A Closer Look

This map covers the West African coast from north of the Kaloum Peninsula and the Loos Islands (now Guinea) south to the Cape Mount Peninsula, in today's Liberia. The future site of Freetown, established in the 1790s, is located near center on the peninsula marked 'Bûrré.' Freetown Harbor, the largest and one of the best natural harbors in Africa, is dubbed 'Pyrates Bay' in the inset.

The inset map also includes soundings, hazards, and anchorage points, while both the inset and main map indicate coastal sand banks. European knowledge of the interior remained quite limited, but some indigenous settlements and ethnic groups are noted and mapping of the Sierra Leone and Sherbro Rivers, where trade was most active, is quite detailed.

The Transatlantic Slave Trade

These coasts were first visited by Europeans when the Portuguese reached the area in the 1460s, after which they returned regularly to trade. Although slavery appears to have been a rare occurrence among the local tribes and kingdoms, strong economic incentives led to increased slave-raiding between groups. The Sierra Leone and Sherbro River were the main sites of trade with Europeans, which was dominated by the slave trade by the 18th century. The English had created a monopoly (the Royal African Company) to manage trade with this part of Africa, but it was supplanted in the early 18th century, creating a free-for-all among private traders that only increased the scale and brutality of the slave trade.

Bunce Island (here as 'Bense I.,'), located near the mouth of the Sierra Leone River, was a key node in the transatlantic slave trade to British colonies in North America, especially South Carolina and Georgia. It had been used by the English since the 1670s, when they built a castle and trading factory there. In the 1720s, José Lopez da Moura, a Luso-African slave trader, seized the island from the British but later abandoned it. Just prior to this map's publication, the island was acquired by Grant, Oswald and Company, which hired Henry Laurens, later President of the Continental Congress, as their business agent in Charleston, South Carolina.

Publication History and Census

Although unattributed, this map most likely was engraved by Isaac Basire. It appeared in Volume II of John Green's A New General Collection of Voyages and Travels, printed in London by Thomas Astley between 1745 - 1747. The inset map is attributed to one 'Mr. Smith.' Earlier publication information at bottom-right looks to have been stricken from the plate, suggesting it had originally belonged to another engraver. The separate map is listed only once in the OCLC, at the National Library of Scotland, while the entire New General Collection is well represented in institutional collections.