The annual volume and regional distribution of the British slave trade, 1780-1807

Journal of African History

Volumn 38, Issue 2, 1997, Pages 187-211

  Behrendt, Stephen D ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BRITISH SLAVERY; EIGHTEENTH CENTURY; HISTORICAL STUDY; REGIONAL PATTERN; SLAVE TRADE; TRADE PATTERN;

AFRICA;

EID: 0031439171     PISSN: 00218537     EISSN: None     Source Type: Journal    
DOI: 10.1017/S0021853797006981     Document Type: Review

References (78)

1. David Richardson, 'The eighteenth-century British slave trade: estimates of its volume and coastal distribution in Africa', Research in Economic History, XII (1989), 151-95; Philip D. Curtin, The Atlantic Slave Trade : A Census (Madison, 1969); Joseph E. Inikori, 'Measuring the Atlantic slave trade: an assessment of Curtin and Anstey', J. Afr. Hist., XVII (1976), 197-223. Roger Anstey produced the first series of annual slave loading data, but only for British vessels in the trade from 1791 to 1807; Roger Anstey, 'The volume and profitability of the British slave trade, 1761-1807', in Stanley L. Engerman and Eugene D. Genovese (eds.), Race and Slavery in the Western Hemisphere : Quantitative Studies (Princeton, 1975), 10-12.
2. David Richardson, 'The eighteenth-century British slave trade: estimates of its volume and coastal distribution in Africa', Research in Economic History, XII (1989), 151-95; Philip D. Curtin, The Atlantic Slave Trade : A Census (Madison, 1969); Joseph E. Inikori, 'Measuring the Atlantic slave trade: an assessment of Curtin and Anstey', J. Afr. Hist., XVII (1976), 197-223. Roger Anstey produced the first series of annual slave loading data, but only for British vessels in the trade from 1791 to 1807; Roger Anstey, 'The volume and profitability of the British slave trade, 1761-1807', in Stanley L. Engerman and Eugene D. Genovese (eds.), Race and Slavery in the Western Hemisphere : Quantitative Studies (Princeton, 1975), 10-12.
3. David Richardson, 'The eighteenth-century British slave trade: estimates of its volume and coastal distribution in Africa', Research in Economic History, XII (1989), 151-95; Philip D. Curtin, The Atlantic Slave Trade : A Census (Madison, 1969); Joseph E. Inikori, 'Measuring the Atlantic slave trade: an assessment of Curtin and Anstey', J. Afr. Hist., XVII (1976), 197-223. Roger Anstey produced the first series of annual slave loading data, but only for British vessels in the trade from 1791 to 1807; Roger Anstey, 'The volume and profitability of the British slave trade, 1761-1807', in Stanley L. Engerman and Eugene D. Genovese (eds.), Race and Slavery in the Western Hemisphere : Quantitative Studies (Princeton, 1975), 10-12.
4. David Richardson, 'The eighteenth-century British slave trade: estimates of its volume and coastal distribution in Africa', Research in Economic History, XII (1989), 151-95; Philip D. Curtin, The Atlantic Slave Trade : A Census (Madison, 1969); Joseph E. Inikori, 'Measuring the Atlantic slave trade: an assessment of Curtin and Anstey', J. Afr. Hist., XVII (1976), 197-223. Roger Anstey produced the first series of annual slave loading data, but only for British vessels in the trade from 1791 to 1807; Roger Anstey, 'The volume and profitability of the British slave trade, 1761-1807', in Stanley L. Engerman and Eugene D. Genovese (eds.), Race and Slavery in the Western Hemisphere : Quantitative Studies (Princeton, 1975), 10-12.
5. For recent debate on Richardson's estimates, see Joseph E. Inikori, 'The volume of the British slave trade, 1655-1807', Cah. Ét. Afr., XXXII (1992), 643-88; David Richardson and Stephen D. Behrendt, 'Inikori's odyssey: measuring the British slave trade, 1655-1807', Cah. Ét. Afr., XXXV (1995), 599-615.
6. For recent debate on Richardson's estimates, see Joseph E. Inikori, 'The volume of the British slave trade, 1655-1807', Cah. Ét. Afr., XXXII (1992), 643-88; David Richardson and Stephen D. Behrendt, 'Inikori's odyssey: measuring the British slave trade, 1655-1807', Cah. Ét. Afr., XXXV (1995), 599-615.
7. For example, Inikori has relied on a Board of Trade document that itemized the slave loadings of 203 ships trading at the Gold Coast, 1755-85; Inikori, 'Measuring the Atlantic slave trade', 211-12; Inikori, 'Volume of the British slave trade', 655. This information on slave loading levels was provided by officials of the London-based Royal African Company (later 'Company of Merchants Trading to Africa') who resided at Gold Coast forts.
8. For example, Inikori has relied on a Board of Trade document that itemized the slave loadings of 203 ships trading at the Gold Coast, 1755-85; Inikori, 'Measuring the Atlantic slave trade', 211-12; Inikori, 'Volume of the British slave trade', 655. This information on slave loading levels was provided by officials of the London-based Royal African Company (later 'Company of Merchants Trading to Africa') who resided at Gold Coast forts.
9. With the exception of the period 1790-1807, these were mortality levels sustained by British slavers or by slave traders from other nations; Richardson, 'Eighteenth-century British slave trade', 156-7.
10. Ibid. 158-63.
11. Ibid. 173. Richardson published slightly revised data in a separate study; David Richardson, 'Slave exports from West and West-Central Africa, 1700-1810: new estimates of volume and distribution', J. Afr. Hist., XXX (1989), 13. The classification of these African regions was defined by Curtin, Atlantic Slave Trade, 128-30.
12. Ibid. 173. Richardson published slightly revised data in a separate study; David Richardson, 'Slave exports from West and West-Central Africa, 1700-1810: new estimates of volume and distribution', J. Afr. Hist., XXX (1989), 13. The classification of these African regions was defined by Curtin, Atlantic Slave Trade, 128-30.
13. Ibid. 173. Richardson published slightly revised data in a separate study; David Richardson, 'Slave exports from West and West-Central Africa, 1700-1810: new estimates of volume and distribution', J. Afr. Hist., XXX (1989), 13. The classification of these African regions was defined by Curtin, Atlantic Slave Trade, 128-30.
14. For example, Richardson increased the percentage of the British slave trade from the Bight of Biafra from 31 to 37 per cent over the eighteenth century; Richardson, 'Eighteenth-century British slave trade', 174; cf. Philip D. Curtin, 'Measuring the Atlantic slave trade', in Engerman and Genovese (eds.), Race and Slavery, 107-28; Anstey, 'Volume and profitability', 12-14.
15. For example, Richardson increased the percentage of the British slave trade from the Bight of Biafra from 31 to 37 per cent over the eighteenth century; Richardson, 'Eighteenth-century British slave trade', 174; cf. Philip D. Curtin, 'Measuring the Atlantic slave trade', in Engerman and Genovese (eds.), Race and Slavery, 107-28; Anstey, 'Volume and profitability', 12-14.
16. For example, Richardson increased the percentage of the British slave trade from the Bight of Biafra from 31 to 37 per cent over the eighteenth century; Richardson, 'Eighteenth-century British slave trade', 174; cf. Philip D. Curtin, 'Measuring the Atlantic slave trade', in Engerman and Genovese (eds.), Race and Slavery, 107-28; Anstey, 'Volume and profitability', 12-14.
17. My data-set of British slave voyages are included in : David Eltis, David Richardson, Stephen D. Behrendt and Herbert S. Klein (eds.), W. E. B. Du Bois Institute's Transatlantic Slave Trade Database, CD-ROM Set and Guidebook (Cambridge, forthcoming).
18. William Collow was the principal British merchant who owned and organized slave voyages that sailed from non-British ports. In 1787-91 he organized ten slave voyages from Le Havre to the Gold Coast and St Domingue or Tobago: Stephen D. Behrendt, 'The journal of an African slaver, 1789-92, and the Gold Coast slave trade of William Collow', History in Africa, XXII (1995), 61-71. Collow's vessels should be classified as French slave voyages; indeed, they are listed in Jean Mettas, Répertoire des expéditions négrières françaises au XVIIIe siècle, eds. Serge and Michèle Daget (2 vols.) (Paris, 1978, 1984).
19. William Collow was the principal British merchant who owned and organized slave voyages that sailed from non-British ports. In 1787-91 he organized ten slave voyages from Le Havre to the Gold Coast and St Domingue or Tobago: Stephen D. Behrendt, 'The journal of an African slaver, 1789-92, and the Gold Coast slave trade of William Collow', History in Africa, XXII (1995), 61-71. Collow's vessels should be classified as French slave voyages; indeed, they are listed in Jean Mettas, Répertoire des expéditions négrières françaises au XVIIIe siècle, eds. Serge and Michèle Daget (2 vols.) (Paris, 1978, 1984).
20. One British vessel, the Infant Ann (103 tons), which sailed from Liverpool on 14 Dec. 1796, made three slave voyages before returning to Liverpool in 1799; Public Record Office [hereafter PRO], BT98/59, 400. Most of the British West India slave vessels were sloops, brigs and schooners that measured less than 100 tons.
21. These six voyages, reported in parliamentary accounts, were made by Liverpool-owned slave vessels sailing under foreign registration. Parliamentary papers also do not report all British vessels which cleared British customs. Gaps in government accounts occur mostly in the London slave trade, as 17 per cent of the London slave voyages are not recorded from 1789 to Apr. 1806. In all, as Richardson suggested, parliamentary papers understate the number of slaves voyages by about 4 per cent: Stephen D. Behrendt, 'The British slave trade, 1785-1807: volume, profitability, and mortality' (Ph.D thesis, University of Wisconsin-Madison, 1993), 20-2.
22. In addition, 28 British vessels were lost, wrecked, captured or condemned during slaving, 78 vessels were captured on the Middle Passage, 53 vessels were lost in the Americas, 31 vessels were captured on the homeward passage and 70 vessels were lost on the homeward passage. Slaves from the 28 above-mentioned voyages were trans-shipped on the Coast. People on board slavers which were 'lost' usually survived as the vessels were abandoned; 19 slave vessels sunk at sea with most crew or slaves perishing.
23. In all, there are slave import records for 2,480 of 3,087 British slave voyages. Either slave exports or imports are reported for 2,514 voyages. For a more detailed discussion of these parliamentary acts and the accuracy of basing coastal loading levels on slave import data, see Behrendt, 'British slave trade, 1785-1807', 41-62.
24. We have tonnage data for vessels making 3,311 of the 3,370 voyages from 1780 to 1807. Tonnage information is lacking for a handful of United States-owned slave vessels sailing from England and for the smaller vessels in the British West Indies-based slave trade. Anstey first estimated slave imports based on annual numbers of slaves landed per ton; Anstey, 'Volume and profitability', 10-12.
25. In the period from I Aug. 1799 to 1807, sources report slave exports for only nine British voyages. British slave voyages 'under-slaved', for example, when they were captured during slaving. One such vessel was the Angola (184 tons), captured in the Gambia River with 170 slaves while trying to load to the legal limit of 216 slaves.
26. For example, in 1789-92, seven London storeships totalling 2,233 tons disembarked 1,271 slaves in Jamaica and the Windward Islands, an average of 0.57 slaves landed per ton.
27. Excluding 'double voyages', 37 West India-based vessels of 3,574 tons landed 3,474 ] slaves in the Americas (an average of 94 slaves per vessel). As shown in Table 3, this ratio of about one slave landed per ton is less than the slave-per-ton ratio for vessels based in England.
28. Sources frequently conflict over the exact number of slaves who were landed in the Americas. For example, five different slave import totals were reported on the Liverpool ship King George in 1798. I believe that different slave import totals measure harbor mortality; Behrendt, 'British slave trade, 1785-1807', 57-8.
29. For example, a parliamentary account reported that the Andalusia (230 tons) landed six slaves at Grenada, whereas a Treasury document reported that the ship sailed from Cape Coast Castle with 300 slaves (PP 1792 (XXXV) 768; PRO, T70/1561). For some voyages, West India gazettes advertised the sale of partial slave cargoes. In 1798, 150 slaves were advertised for sale from the 270-ton Liverpool slave ship King William, which was allowed to embark 404 slaves on the African coast. This ship was captured earlier off Martinique by the French and carried into Guadeloupe before it was recaptured by HM brig Diligence. The French privateer, presumably, carried off the majority of slaves; Royal Gazette (Kingston), 29 Dec. 1798- 5 Jan. 1799; Lloyd's List, 5 Mar. 1799.
30. For example, a parliamentary account reported that the Andalusia (230 tons) landed six slaves at Grenada, whereas a Treasury document reported that the ship sailed from Cape Coast Castle with 300 slaves (PP 1792 (XXXV) 768; PRO, T70/1561). For some voyages, West India gazettes advertised the sale of partial slave cargoes. In 1798, 150 slaves were advertised for sale from the 270-ton Liverpool slave ship King William, which was allowed to embark 404 slaves on the African coast. This ship was captured earlier off Martinique by the French and carried into Guadeloupe before it was recaptured by HM brig Diligence. The French privateer, presumably, carried off the majority of slaves; Royal Gazette (Kingston), 29 Dec. 1798- 5 Jan. 1799; Lloyd's List, 5 Mar. 1799.
31. Regarding this reduction in slave mortality in the British slave trade, see Behrendt, 'British slave trade, 1785-1807', 169-88.
32. Richardson estimated that 481 slave voyages sailed from London, 1780-1807. Including 'double voyages', I calculate that there were 526 London slave voyages (a 9-4 per cent difference).
33. Richardson and Behrendt, 'Inikori's odyssey', 606.
34. Indeed, Richardson acknowledged that his trading data for the year 1794 were inaccurate because a large number of British slave vessels were captured; Richardson, 'Eighteenth-century British slave trade', 177, n.17.
35. Curtin, Atlantic Slave Trade, 136.
36. This is important to consider, as all studies published since 1969 have revised Curtin's benchmark totals upwards; Joseph E. Inikori and Stanley L. Engerman, 'Introduction: gainers and losers in the Atlantic slave trade', in Joseph E. Inikori and Stanley L. Engerman (eds.), The Atlantic Slave Trade : Effects on Economies, Societies, and Peoples in Africa, the Americas, and Europe (Durham, 1992), 5-6. Eltis recently produced new data on the volume of the early British slave trade, lowering separate estimates made by Richardson and Inikori in 1989-92; David Eltis, 'The volume and African origins of the British slave trade before 1714', Cah. Ét. Afr., XXXV (1995), 617-25.
37. This is important to consider, as all studies published since 1969 have revised Curtin's benchmark totals upwards; Joseph E. Inikori and Stanley L. Engerman, 'Introduction: gainers and losers in the Atlantic slave trade', in Joseph E. Inikori and Stanley L. Engerman (eds.), The Atlantic Slave Trade : Effects on Economies, Societies, and Peoples in Africa, the Americas, and Europe (Durham, 1992), 5-6. Eltis recently produced new data on the volume of the early British slave trade, lowering separate estimates made by Richardson and Inikori in 1989-92; David Eltis, 'The volume and African origins of the British slave trade before 1714', Cah. Ét. Afr., XXXV (1995), 617-25.
38. This fact is not surprising as British slaving merchants carried assorted cargoes for specific African trading locations. For the Liverpool trade in 1783-7, 1797-9, and 1806-7, we find that 626 of 704 voyages slaved at the ' intended ' location. Other voyages slaved near their intended locations; for example, they sailed for New Calabar but slaved at Bonny. British captains were able to purchase slaves with poorly assorted cargoes when there were few European competitors.
39. Stephen D. Behrendt, 'The captains in the British slave trade from 1785 to 1807', Transactions of the Historic Society of Lancashire and Cheshire, CXL (1991), 105-6, and 'British slave trade, 1785-1807', 122-3. Trading goods were sometimes left behind in Africa, leading British merchants to send a slave vessel to the same location on subsequent voyages; Institute of Commonwealth Studies (ICS), Simon Taylor Archive, Simon Taylor to Robert Taylor, St. Mary's, 29 Dec. 1803. Several British merchants had fixed factories on the African coast to centralize their slave purchases.
40. Stephen D. Behrendt, 'The captains in the British slave trade from 1785 to 1807', Transactions of the Historic Society of Lancashire and Cheshire, CXL (1991), 105-6, and 'British slave trade, 1785-1807', 122-3. Trading goods were sometimes left behind in Africa, leading British merchants to send a slave vessel to the same location on subsequent voyages; Institute of Commonwealth Studies (ICS), Simon Taylor Archive, Simon Taylor to Robert Taylor, St. Mary's, 29 Dec. 1803. Several British merchants had fixed factories on the African coast to centralize their slave purchases.
41. For British voyages which slaved at multiple locations, I divided the estimated number of slave exports by the number of trading sites. For example, if 300 slaves were shipped from a voyage which traded at New Calabar, Bonny, and Old Calabar, I assigned 100 slave exports to each location.
42. Adam Jones and Marion Johnson, 'Slaves from the Windward Coast', J. Afr. Hist., XXI (1980), 17-34.
43. Regarding Liverpool slave vessels and privateers, see Gomer Williams, History of the Liverpool Privateers and Letters of Marque with an Account of the Liverpool Slave Trade (London and Liverpool, 1897).
44. British vessels disembarked slaves at Trinidad and the Danish West Indies prior to conquest, though at a lower volume.
45. Seymour Drescher, Econocide : British Slavery in the Era of Abolition (Pittsburgh, 1977), 94-102. The order-in-council of 1805 which limited slave deliveries to the Guianas thus had a direct impact on the volume of the trade. The reopening of Charleston to transatlantic slave vessels in Dec. 1803, though, provided an outlet which in part counterbalanced the loss of the Guianas market to British slavers. The parliamentary regulations of 1788 and 1799, which reduced slave loading levels, did not reduce trade volume. During the period 1800-6, British vessels embarked, on average, 34,920 slaves per year. In contrast, an average of 33,457 slaves were embarked annually on British vessels which sailed during the peacetime years, 1783-8.
46. West India planters in financial difficulty did not complain about the price of slaves. Instead, they focused their grievances on the British Navigation Acts which raised the price of foodstuffs and on the sugar duties.
47. Richard B. Sheridan, 'The slave trade to Jamaica, 1702-1808', in B. W. Higman (ed.), Trade, Government and Society in Caribbean History, 1700-1920 (London, 1983), 9-11, and 'The crisis of slave subsistence in the British West Indies during and after the American revolution', William and Mary Quarterly, XXXIII (1976), 615-41. Destructive hurricanes also hit the islands in 1784, 1785 and 1786.
48. Richard B. Sheridan, 'The slave trade to Jamaica, 1702-1808', in B. W. Higman (ed.), Trade, Government and Society in Caribbean History, 1700-1920 (London, 1983), 9-11, and 'The crisis of slave subsistence in the British West Indies during and after the American revolution', William and Mary Quarterly, XXXIII (1976), 615-41. Destructive hurricanes also hit the islands in 1784, 1785 and 1786.
49. In 1784, Jamaica planter Simon Taylor sought a loan of £20,000 from the London house of Hibbert, Purrier & Co. to purchase slaves and pay outstanding debts; ICS, Simon Taylor Archive, Simon Taylor to Hibbert, Purrier & Co., Kingston, 25 May 1784.
50. In Sept. 1792 one Liverpool merchant remarked that 'Everything in the shape of a ship that can be come at is fitting out for Africa'; quoted by Joseph E. Inikori, 'Market structure and the profits of the British African trade in the late eighteenth century', Journal of Economic History, XLI (1981), 760.
51. ICS, Simon Taylor Archive, John Taylor to Simon Taylor, Kingston, 29 Nov. 1791.
52. For Jamaica slave prices: PRO, CO 137/91, 60; Royal Gazette (Kingston), 23-30 June 1792, 5-12 Jan. 1793. For slave prices in Africa : David Richardson, 'Prices of slaves in West and West-Central Africa: toward an annual series, 1698-1807', Bulletin of Economic Research, XLIII (1991), 40-1.
53. For Jamaica slave prices: PRO, CO 137/91, 60; Royal Gazette (Kingston), 23-30 June 1792, 5-12 Jan. 1793. For slave prices in Africa : David Richardson, 'Prices of slaves in West and West-Central Africa: toward an annual series, 1698-1807', Bulletin of Economic Research, XLIII (1991), 40-1.
54. Continued large supplies of slaves reached trading sites in West-Central Africa because of drought in the 1780s and 1790s; Joseph C. Miller, 'The significance of drought, disease, and famine in the agriculturally marginal zones of West-Central Africa', J. Afr. Hist., XXIII (1982), 17-61.
55. Behrendt, 'British slave trade, 1785-1807', 125-6. James Rogers of Bristol was the largest merchant who declared bankruptcy and left the trade. Rogers organized 41 slave voyages in the years 1785-92.
56. National Maritime Museum, Log/M/21, f. 89.
57. As a Grenada planter stated: 'During the Insurrection in this Island, the whole, excepting the Town of Saint George for a time was in possession of the Insurgents and the cultivation of the Estates entirely given up; as order was so lately restored, little could be expected for the crop of 1797 ' : PRO, CO 106/12, f. 86, document dated 20 June 1797.
58. ICS, Simon Taylor Archive, Simon Taylor to Robert Taylor, Kingston, 3 Dec. 1798.
59. PRO, CO 389/23, ff. 6-60.
60. PRO, T70/1560, extracts from letters of John Clemison, Benin, 19 Dec. 1789; PRO, T70/1562, petition of John Dawson, Liverpool, Dec. 1790.
61. For example, slave voyages organized by Liverpool merchant William Davenport, 1763 76, opened the British slave trade at Old Calabar and the Cameroons; David Richardson, 'Profits in the Liverpool slave trade: the accounts of William Davenport, 1757-1784', in Roger Anstey and P. E. H. Hair (eds.), Liverpool, the African Slave Trade, and Abolition (Liverpool, 1976), 65.
62. Boats' death is noted in Williams, Liverpool Privateers, 485. In 1790-2 slave voyages organized by William Boats shipped more than 8,000 slaves from the Bight of Biafra to the British West Indies.
63. PRO, T70/1545, Parke and Heywood to Richard Miles, Liverpool, 9 Sept. 1782. Shortages of slaves forced vessels to remain longer on the Coast, increasing voyage risk. Liverpool merchant Joseph Fowden mentioned that there were 'at present no Ships going to Anamaboe from this place, owing to the long stay on the Coast': PRO, T70/1545, Joseph Fowden to Richard Miles, Liverpool, 2 Nov. 1782.
64. PRO, T70/1554, Robert Chesshire to James Morgue, Amanda, 16 Oct. 1784. In May 1789, British captains successfully conspired to lower the price of Anomabu slaves by 15 to 20 per cent. By August, however, increased competition on the Coast raised the price to former levels ; PRO,T70/1559, Cape Coast Castle Council to African Committee, 20 Aug. 1789.
65. John Adams, Remarks on the Country Extending from Cape Palmas to the River Congo (London, 1966), 217-18. Regarding Angola prices, see Joseph C. Miller, 'Slave prices in the Portuguese southern Atlantic, 1600-1830', in Paul E. Lovejoy (ed.), Africans in Bondage : Studies in Slavery and the Slave Trade (Madison, 1986), 71.
66. John Adams, Remarks on the Country Extending from Cape Palmas to the River Congo (London, 1966), 217-18. Regarding Angola prices, see Joseph C. Miller, 'Slave prices in the Portuguese southern Atlantic, 1600-1830', in Paul E. Lovejoy (ed.), Africans in Bondage : Studies in Slavery and the Slave Trade (Madison, 1986), 71.
67. For the important West-Central African region, sources report the trading sites for voyages which embarked 74,379 of 188,356 slaves. In this sample, the principal trading sites for British slavers were: Congo River (50.3 per cent); Ambriz (14.4 per cent); Melimba (12.1 per cent); Loango (10.8 per cent); and Cabinda (8.2 per cent).
68. With annual exports of 7,000-7,500 slaves (1780-1807), Bonny was one of the three greatest slave-trading ports on the West African coast; only Luanda and Whydah supported such a large supply of slaves. For new data on Whydah, see David Eltis and David Richardson, 'West Africa and the transatlantic slave trade: new evidence of long run trends', Slavery and Abolition (May 1997). For Luanda, see Jose C. Curto, 'A quantitative reassessment of the legal Portuguese slave trade from Luanda, Angola, 1710-1830', African Economic History, XX (1992), 1-25. Captain Adams believed that about 20,000 slaves were sold annual from Bonny: Adams, Remarks, 129. This number appears to be an exaggeration.
69. With annual exports of 7,000-7,500 slaves (1780-1807), Bonny was one of the three greatest slave-trading ports on the West African coast; only Luanda and Whydah supported such a large supply of slaves. For new data on Whydah, see David Eltis and David Richardson, 'West Africa and the transatlantic slave trade: new evidence of long run trends', Slavery and Abolition (May 1997). For Luanda, see Jose C. Curto, 'A quantitative reassessment of the legal Portuguese slave trade from Luanda, Angola, 1710-1830', African Economic History, XX (1992), 1-25. Captain Adams believed that about 20,000 slaves were sold annual from Bonny: Adams, Remarks, 129. This number appears to be an exaggeration.
70. With annual exports of 7,000-7,500 slaves (1780-1807), Bonny was one of the three greatest slave-trading ports on the West African coast; only Luanda and Whydah supported such a large supply of slaves. For new data on Whydah, see David Eltis and David Richardson, 'West Africa and the transatlantic slave trade: new evidence of long run trends', Slavery and Abolition (May 1997). For Luanda, see Jose C. Curto, 'A quantitative reassessment of the legal Portuguese slave trade from Luanda, Angola, 1710-1830', African Economic History, XX (1992), 1-25. Captain Adams believed that about 20,000 slaves were sold annual from Bonny: Adams, Remarks, 129. This number appears to be an exaggeration.
71. French slave vessels sailing from 1790 to 1792 shipped only about about 1,500 slaves from the Bight of Biafra, and the majority of these slaves were loaded near Gaboon; Mettas, Répertoire. The French slave trade ended by 1793.
72. As the Abolition Act prohibited British slave vessels from clearing customs after I May 1807 (though vessels sailed through August), slave export data for 1807 approximate half-year totals.
73. Paul E. Lovejoy and David Richardson, ' Competing markets for male and female slaves: prices in the interior of West Africa, 1780-1850', Int. J. Afr. Hist. Studies, XXVIII (1995), 286.
74. Captain John Adams suggested that Old Calabar's high port dues encouraged British traders to slave at Bonny; A. J. H. Latham, Old Calabar, 1600-1891 : The Impact of the International Economy Upon a Traditional Society (Oxford, 1973), 19-20.
75. Robin Law, 'Slave-raiders and middlemen, monopolists and free-traders: the supply of slaves for the Atlantic trade in Dahomey, c. 1715-1850', J. Afr. Hist., XXX (1989), 55-7, and The Oyo Empire, c. 1600 - c. 1836 : A West African Imperialism in the Era of the Atlantic Slave Trade (Oxford, 1977), 274.
76. Robin Law, 'Slave-raiders and middlemen, monopolists and free-traders: the supply of slaves for the Atlantic trade in Dahomey, c. 1715-1850', J. Afr. Hist., XXX (1989), 55-7, and The Oyo Empire, c. 1600 - c. 1836 : A West African Imperialism in the Era of the Atlantic Slave Trade (Oxford, 1977), 274.
77. ICS, Simon Taylor Archive, Simon Taylor to Robert Taylor, Kingston, 29 Jan. 1799; Simon Taylor to Robert Taylor, St. Thomas in the East, 9 Oct. 1799.
78. From a sample of 453 British vessels which slaved only at Bonny, 77 voyages sailed from England in July, 66 sailed in June, and 64 sailed in May. Grouped in four-month totals: 64 vessels sailed in Jan.-Apr., 256 vessels sailed in May-Aug. and 133 vessels sailed in Sept.-Dec.