A careful review of the literature has failed to disclose any explanation of the mechanism of vomiting in peritonitis which is supported by experimental facts. No recorded attempt by critical experiment to determine the nature of the emetic stimulus and to discover its manner of action could be found, although the phrase "peritoneal irritation" was noted in practically every work on peritonitis and vomiting. The present study was undertaken because of the apparent lack of proof that vomiting in peritonitis is really due to irritation of the peritoneum.
Since the most important subjective evidence on which the interpretation and diagnosis of acute peritoneal inflammation are based consists of the history of abdominal pain, nausea and vomiting, any contribution that leads to a better understanding of the origin and nature of the symptoms is of direct interest to the clinician.
Although the emetic stimulus has usually been considered to be a