This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
When foreign bodies have been accidentally swallowed, such as coins, buttons, safety or other pins, large cherry, plum, or other fruit stones, fish bones, chicken bones, or pieces of clam or oyster shells, if the patient is seen within two or three hours, the object having passed beyond the reach of the finger or oesophageal pro-bang, an emetic may be given. If this fails to return the foreign body from the stomach, the patient should eat large quantities of bread, oatmeal, or potatoes. The plan of this treatment is to furnish a bulk of faecal matter, which in the intestines may envelop the pin or bone, and prevent its sharp or roughened ends from injuring the mucous membrane. Six or eight hours later a dose of castor oil should be given. By this means many dangerous objects may be safely voided. If the foreign body does not appear after the oil has acted, the treatment should be repeated next day, and the stools must be carefully watched until it is recovered. Experience has shown that the search should not be abandoned for at least eight or ten days.
Men who earn a precarious livelihood by publicly exhibiting themselves as possessing "iron stomachs," and who swallow broken glass, coins, nails, etc., take considerable risk from exciting grave injury or peritonitis, but by eating the foreign bodies only when the stomach is nearly full, and by following the treatment outlined above, they manage to escape death.