The medical evidence at the trial was favourable to the accused. Orfila, the famous chemist of that day, said that, though the symptoms in Auguste Ballet's case might be attributed to poisoning by acetate of morphia or some other vegetable poison, at the same time they could be equally well attributed to sudden illness of a natural kind. The liquids, taken from the stomach of Ballet, had yielded on analysis no trace of poison of any sort. The convulsive symptoms present in Ballet's case were undoubtedly a characteristic result of a severe dose of acetate of morphia.(14) Castaing said that he had mixed the acetate of morphia and tartar emetic together, but in any case no trace of either poison was found in Auguste's body, and his illness might, from all appearances, have been occasioned by natural causes. Some attempt was made by the prosecution to prove that the apoplexy to which Hippolyte Ballet had finally succumbed, might be attributed to a vegetable poison; one of the doctors expressed an opinion favourable to that conclusion "as a man but not as a physician." But the evidence did not go further. (14) It was asserted some years later by one medical authority in Palmer's case that it might have been morphia and not strychnine that had caused the tetanic symptoms which preceded Cook's death. To the young priest-like doctor the ordeal of his trial was a severe one. It lasted eight days. It was only at midday on the sixth day that the evidence was concluded. Not only was Castaing compelled to submit to a long interrogatory by the President, but, after each witness had given his or her evidence, the prisoner was called on to refute or explain any points unfavourable to him. This he did briefly, with varying success; as the trial went on, with increasing embarrassment. A great deal of the evidence given against Castaing was hearsay, and would have been inadmissible in an English court of justice. Statements made by Auguste to other persons about Castaing were freely admitted. But more serious was the evidence of Mlle. Percillie, Auguste's mistress. She swore that on one occasion in her presence Castaing had reproached Auguste with ingratitude; he had complained that he had destroyed one copy of Hippolyte Ballet's will, and for Auguste's sake had procured the destruction of the other, and that yet, in spite of all this, Auguste hesitated to entrust him with 100,000 francs. Asked what he had to say to this statement Castaing denied its truth. He had, he said, only been in Mlle. Percillie's house once, and then not with Auguste Ballet. Mlle. Percillie adhered to the truth of her evidence, and the President left it to the jury to decide between them.