Eructation or regurgitation is readily produced and of frequent occurrence in infancy, on account of the vertical position and more cylindrical outline of the stomach at this period of life.

Babies suckled at a freely-secreting breast often eructate, though they may be in the best possible health. In these cases, the supply of food being large, the infant, as it lies at the breast, is apt to draw more than it needs and more than it can digest, and the stomach, through a wise provision of nature, rids itself of the superabundance by the simple act of regurgitation. In this process, which in reality is an evidence of health, there is no violent muscular effort, as in retching or vomiting, nor any evidence of nausea, and the material ejected is the breast milk alone, either entirely unaltered or slightly curdled.

In older children, expulsion of the contents of the stomach, or vomiting, may also occur after the stomach has been overladen. If the act be followed by relief from a feeling of general distress, headache and pain in the upper abdomen, it is not to be regarded as a symptom of disease.

Examples of Variations in Disease. - Vomiting, with its violent muscular effort and the attendance of the train of symptoms embraced under the term nausea - namely, paleness, languor, faintness and an increased secretion of saliva - occurs in many different conditions. It may indicate disease of the stomach, of the intestines, of the lungs or their pleural investment, and of the brain; or it may be an initial symptom of one of the eruptive fevers, scarlet fever or measles, for example, which condition, when existent, can only be determined by closely observing the special case.

The character of the material ejected from the stomach is more definite. Thus, the expulsion of mucus is a symptom of gastric catarrh. The regurgitation of mouthfuls of curdled milk, partly digested food and liquid, so sour that it causes a grimace to pass over the face, is an indication of dyspepsia with fermentation and the formation of an irritant acid. The appearance of lumbricoid worms in the vomit, a not very infrequent occurrence, shows, without dispute, the existence of these parasites in the digestive canal.