038840engo 2

The slave trade

and the Atlantic economies 1451-1870

57

which this article tries to tackle, therefore, is the extent to which the movements

of the various economies under review were accelerated or retarded by the

slave trade in those crucial stages of development. The analysis draws on the

concept of dynamic gains from international trade as opposed to the static gains

of classical analysis.*

Magnitude of the external slave trade

One problem which is central to our question is the magnitude of the external
slave trade from Africa during the period 1451-1870. This means a computation
of the total number of slaves actually carried away from sub-Saharan Africa by
way of the Sahara, the Atlantic, the Red Sea and the Indian Ocean, during
that period. From the point of view of the European sector of the Atlantic,
this is necessary because the development of resources required by the trade
forms an important part of the analysis and this will have to be weighted by
the estimated magnitude of the European portion of the trade. For the African
part of the analysis the computed magnitude will form a useful starting point
for an estimate of the demographic impact of the trade and the consequences of
that for economic development in the regions affected.
Most writers dealing with the slave trade across the Sahara and the
Atlantic have always found it necessary to estimate the total number of slaves
involved. For the Atlantic portion, the most recent of these estimates is that
of Professor Curtin,^5 which was based on published data. However, his global
estimates have now been shown to be generally on the low side of the mark.^6
At present much work is going on relating to the number of slaves exported
from Africa by way of the Atlantic trade. It may take another decade or more
before the outcome can be stated in terms of global figures. For the purposes of
the analysis in this article, the figure of 11 million slaves provided by Professor
Curtin has been taken as representing the barest minimum for the Atlantic
trade. This, together with the European share of the unknown magnitude of
the Indian Ocean trade, makes up the European portion of the external slave
trade from Africa.
For the trans-Saharan trade, a recent attempt to summarize the impli-
cations of some of the existing estimates put the total number of slaves taken
away from sub-Saharan Africa to meet the demands of the desert trade, for the
whole period 850-1910, at 10 million. The distribution of this total over time
shows that for our period, 1451-1870, a little under 6 million people were taken
away.^7 These data are extremely weak, and some think the present estimate may
be on the high side.^8 If the trans-Saharan figure should be proved to be an over-
estimate, this may compensate to some extent the underestimate for the trans-
Atlantic trade.
As for the slave trade from East Africa to the Red Sea, Arabia, the Persian