In another class of cases, where it became necessary to show the mental condition or bodily health of the slave, his declarations have been held to be admissible, even in a suit against a white person; but they must be proved by white testimony. Thus, in an action for breach of covenant in not teaching a slave bound apprentice to the business of coach-making, the defendant having offered to prove, that, when he wished to instruct the slave, and threatened to punish him, if he did not apply himself, the latter, as soon as the defendant was out of the way, would declare “that he did [not] care about learning the trade, it was no profit to him, and if he could avoid the lash, it was all he cared for,”--it was held by that prominent magistrate, Mr. Justice Gaston, of North Carolina, that the declarations of the slave were admissible, “because his disposition and temper are subjects of investigation, and these cannot be ascertained but through the medium of such external signs.”[61] In another case the same question occurred under these circumstances: A slave was hired by his master to work in certain gold mines; but, while busy at the bottom of a shaft one hundred and eighty feet deep, he was struck on the head by an iron drill weighing five pounds, which fell from the top, and his skull was fractured so that trepanning became necessary, and “a large piece of the skull-bone was cut out.” In an action by the master for damages, Judge Pearson commented on this rule of evidence: “It being material to ascertain the bodily condition of the slave, his complaints of headache when exposed to the sun, and his declarations that he was unable to work in the sun or to endure hard labor are admissible.… The statute excluding the testimony of a slave or free person of color against a white man has no application. The distinction between natural evidence and personal evidence, or the testimony of witnesses, is clear and palpable. The actions, looks, and barking of a dog are admissible as natural evidence upon a question as to his madness. So the squealing and grunts or other expression of pain made by a hog are admissible upon a question as to the extent of an injury inflicted on him. This can in no sense be called the testimony of the dog or the hog. The only advantage of this natural evidence, when furnished by brutes, over the same kind of evidence, when furnished by human beings, whether white or black, is, that the latter, having intelligence, may possibly have a motive for dissimulation, whereas brutes have not; but the character of the evidence is the same, and the jury must pass upon its credit.”[62]