8. _Hired slaves._ It is for the interest of those who hire slaves to get as much out of them as they can; the temptation to overwork them is powerful. If it be said that the master could, in that case, recover damages, the answer is, that damages would not be recoverable in law unless actual injury--enough to impair the power of the slave to labor, be _proved._ And this ordinarily would be impossible, unless the slave has been worked so greatly beyond his strength as to produce some fatal derangement of the vital functions. Indeed, as all who are familiar with such cases in southern courts well know, the proof of actual injury to the slave, so as to lessen his value, is exceedingly difficult to make out, and every hirer of slaves can overwork them, give them insufficient food, clothing, and shelter, and inflict upon them nameless cruelties with entire impunity. We repeat then that it is for the _interest_ of the hirer to push his slaves to their utmost strength, provided he does not drive them to such an extreme, that their constitutions actually give way under it, while in his hands. The supreme court of Maryland has decided that, 'There must be _at least a diminution of the faculty of the slave for bodily labor_ to warrant an action by the master.'--_1 Harris and Johnson's Reports, 4._ 9. _Slaves under overseers whose wages are proportioned to the crop which they raise._ This is an arrangement common in the slave states, and in its practical operation is equivalent to a bounty on _hard driving_--a virtual premium offered to overseers to keep the slaves whipped up to the top of their strength. Even where the overseer has a fixed salary, irrespective of the value of the crop which he takes off, he is strongly tempted to overwork the slaves, as those overseers get the highest wages who can draw the largest income from a plantation with a given number of slaves; so that we may include in this last class of slaves, the majority of all those who are under overseers, whatever the terms on which those overseers are employed.