All the arts, agricultural and industrial, declined during the flourishing days of the slave-trade, when the selling of captive slaves furnished the conquerors an easy road to wealth and to the possession of much that their own labor alone had formerly provided. Gold is an important commodity and, stored in quills, is used as a medium of exchange; but, strangely enough, it seems only in more modern times to have been fashioned into coins. The labor is divided into well-defined crafts. Besides those already mentioned, there are tailors, musicians, architects who are also builders, barbers who also extract teeth, and even manicurists. Slave-labor is much in demand; for here, as throughout the world, until modern times, wherever agricultural and mechanical industries flourished, slavery has prevailed. And just as the ancient and modern monarchies have depended upon force of arms to supply the slaves needed, so has it been with the negro monarchies. Professor Ely, in his _Political Economy_, argues, from this universal practice doubtless, that slavery is both right and wrong. “There is a time in human development when slavery represents a step in human progress, the best and longest that men were able to take. Such a step is always right. It is wrong, when men have learned how to do better.” Upon this view of the case, a host of African explorers and observers have testified to what they regard as the obvious advantages of the well-nigh universal slave-system of the more progressive tribes. They testify, too, to its partially patriarchal character in the agricultural regions, where the use of slaves, as sacrifices to the gods or offerings upon the death of a king, is practically never found. As an offset, however, to this rather roseate picture, is the even more general witness to the fact that slaves in this zone run away whenever opportunity offers, and, if chance favors them, well supplied with the goods and cattle of their masters to comfort them along the way.