At last he had made money enough by practice to retire. His parting gift to his profession was contained in “The Questions of Aural Surgery,” a work of standard value; and his “Atlas of Diseases of the Membrana Tympani.” In March 1874 he retired, but with a constitution deeply injured by overwork and excess of feeling and thought. His father had died the year before; his mother died in 1874. He continued incessantly working, writing, thinking, studying mankind in the streets and alleys of London, or in the colliers’ cottages in South Wales, and came to suffer much from sleeplessness. When he set sail in the autumn of 1875 for the Azores, where Mrs. Hinton had preceded him, he was already seriously ill. At last he was seized with inflammation of the brain, and died on December 16, 1875, a martyr to his intense passion for the good of mankind. Of his intellectual, ethical, and religious views this is not the place to speak at large; his books must be left to explain themselves to kindred spirits. FOOTNOTES: [23] Reprinted by the Association for the Advancement of Medicine by Research, 1882. CHAPTER XXVII. _SIR R. CHRISTISON, SWAINE TAYLOR, AND POISON DETECTION._ Although the detection of crimes of poisoning is but one of the departments of service which the medical profession is able to render to the law, yet it is one which has very largely attracted public attention, owing to the many awful aspects of death by poisoning, and the helplessness which mankind has always felt in regard to these crimes. Latterly the skill displayed in the detection of the existence of poisons after the death of the victims has set at rest many of the doubts as to the certainty of judgment in regard to poisoning, and the discovery of antidotes to many poisons has supplied a means of remedy in numerous cases before it is too late. It is obvious that these results could only begin to be realised when chemistry had made considerable progress; and consequently it was not till 1813 that a young doctor, the celebrated Orfila, published in Paris the first part of a treatise on Poisons, which was subsequently merged in his “Legal Medicine,” 1821-3. The names most conspicuous in founding this new department of investigation in Great Britain are those which stand at the head of this chapter. * * * * * ROBERT CHRISTISON, one of the twin sons of Alexander Christison, many years Professor of Humanity in Edinburgh University, was born at Edinburgh in July 18, 1797. After a complete education, in arts at the University, he finally chose the medical profession, and was for two years and a half resident assistant in the Royal Infirmary. Taking his M.D. degree in 1819, he spent the next eighteen months at St. Bartholomew’s Hospital, London, and in Paris, where he worked in the laboratory of Robiquet at practical chemistry, and studied toxicology with Orfila himself.