The coast is the natural habitat of the middleman. One strip of seaboard produces a middleman people, and then sends them out to appropriate other littorals, if geographic conditions are favorable; otherwise it is content with the transit trade of its own locality. It breeds essentially a race of merchants, shunning varied production, nursing monopoly by secrecy and every method to crush competition. The profits of trade attract all the free citizens, and the laboring class is small or slave. Expansion landward has no attraction in comparison with the seaward expansion of commerce. The result is often a relative dearth of local land-grown food stuffs. King Hiram of Tyre, in his letter to King Solomon, promised to send him trees of cedar and cypress, made into rafts and conveyed to the coast of Philistia, and asked in return for grain, "which we stand in need of because we inhabit an island." The pay came in the form of wheat, oil, and wine. But Solomon furnished a considerable part of the laborers--30,000 of them--who were sent, 10,000 at a time, to Mount Lebanon to cut the timber, apparently under the direction of the more skilful Sidonian foresters.[506] A type of true coast traders is found in the Duallas of the German Kamerun, at the inner angle of the Gulf of Guinea. Located along the lower course and delta of the Mungo River where it flows into the Kamerun estuary, they command a good route through a mountainous country into the interior. This they guard jealously, excluding all competition, monopolizing the trade, and imposing a transit duty on all articles going to and from the interior. They avoid agriculture so far as possible. Their women and slaves produce an inadequate supply of bananas and yams, but crops needing much labor are wholly neglected, so that their coasts have a reputation for dearness of provisions.[507] Along the 4,500 miles of West African coast between the Senegal and the Kunene rivers the negro's natural talent for trade has developed special tribes, who act as intermediaries between the interior and the European stations on the seaboard. Among these we find the Bihenos and Banda of Portuguese Benguela, who fit out whole caravans for the back country; the Portuguese of Loanda rely on the Ambaquistas and the Mbunda middlemen. The slave trade particularly brought a sinister and abnormal activity to these seaboard tribes,[508] just as it did to the East Coast tribes, and stimulated both in the exploitation of their geographic position as middlemen.[509] [Sidenote: Monopoly of trade with the hinterland.]