people, both slave and free." Individuals lost their connection to families and clans. Added to the earlier colonists combining slaves from different tribes, many ethnic Africans lost their knowledge of varying tribal origins in Africa. Most were descended from families that had been in the United States for many generations. The firm of Franklin and Armfield was a leader in this trade. In the 1840s, almost 300,000 slaves were transported, with Alabama and Mississippi receiving 100,000 each. During each decade between 1810 and 1860, at least 100,000 slaves were moved from their state of origin. In the final decade before the Civil War, 250,000 were transported. Michael Tadman wrote in Speculators and Slaves: Masters, Traders, and Slaves in the Old South (1989) that 60–70% of inter-regional migrations were the result of the sale of slaves. In 1820, a slave child in the Upper South had a 30% chance of being sold South by 1860. The death rate for the slaves on their way to their new destination across the American South was less than that suffered by captives shipped across the Atlantic Ocean, but mortality nevertheless was higher than the normal death rate. Slave traders transported two-thirds of the slaves who moved West. Only a minority moved with their families and existing master. Slave traders had little interest in purchasing or transporting intact slave families; in the early years, planters demanded only the young male slaves needed for heavy labor. Later, in the interest of creating a "self-reproducing labor force", planters purchased nearly equal numbers of men and women. Berlin wrote: The internal slave trade became the largest enterprise in the South outside the plantation itself, and probably the most advanced in its employment of modern transportation, finance, and publicity. The slave trade industry developed its own unique language, with terms such as "prime hands, bucks, breeding wenches, and "fancy girls" coming into common use. The expansion of the interstate slave trade contributed to the "economic revival of once depressed seaboard states" as demand accelerated the value of slaves who were subject to sale. Some traders moved their "chattels" by sea, with Norfolk to New Orleans being the most common route, but most slaves were forced to walk overland. Others were shipped downriver from such markets as Louisville on the Ohio River, and Natchez on the Mississippi. Traders created regular migration routes served by a network of slave pens, yards