To aid the administration of justice in cases of homicide is not only the most useful, but the most frequent, application of medical jurisprudence; this subject, as well for its complexity as for its importance, must be subdivided into many heads. It is first necessary that the medical practitioner should determine by examination, inspection, or dissection, whether the matter ought to be referred to the criminal tribunals, or whether the decease of the party is to be attributed to any of those natural causes, which are generally classed as “Death by the Visitation of God.” In some instances this examination will take place in aid of the coroner’s inquest, in others it will be preparatory to it; in both cases it is equally important that it should be minutely, faithfully, and ably conducted; for it is on the medical report that the first impressions will be founded, and the prejudices created by it in the public mind may not easily be effaced by any subsequent investigation. If, however, it be determined that the cause of death has been violent, it is then necessary to enquire to which of the classes of homicide the act is to be attributed. “Homicide, properly so called, is either against a man’s own life, or that of another.” 1 _Hawk. P. C._ 102. The first offence constitutes the crime of suicide or _felo de se_. The second has many varieties; it may be justifiable, excusable, or wilful; and this last again, may be with, or without, malice prepense, which constitutes the difference between manslaughter and murder; both are felony, the one with,[1] the other without, the benefit of clergy; to these and their numerous subdivisions we shall separately direct the attention of our reader; having first, by a general view of the physiology of death, and some practical observations on the best modes of investigation, prepared the way for a minuter examination of many of those various modes of destruction to which human life is liable. OF REAL AND APPARENT DEATH.