If one dispassionately regards this question, and if any of our methods for the study of gastric secretion are reliable, one must be convinced step by step in the laboratory of the uselessness of mechanical stimulation. In the case of dogs with an ordinary gastric fistula, and failing some special reason, not a drop of gastric juice ever escapes from the stomach other than during the digestive period. How could this be the case if the mechanical stimulus were effective, since the inner rim of the fistula-tube is continuously in contact with the gastric mucous membrane? The same holds good for the dog with resected stomach. During the experiment a glass or india-rubber tube is brought sufficiently far into the _cul-de-sac_ to catch the juice, and yet not a drop flows through the tube, nor does its inner surface ever become acid, so long as true secretory conditions are absent. Moreover, the tube has tolerably often to be taken out and set right. In the ordinary gastric fistula in dogs, when the operation has lasted a long time--over a year--folds of mucous membrane are often formed in the neighbourhood of its inner orifice which completely close the tube. In these cases a long, thick, perforated metal tube has to be passed in deeply, and yet the manipulation of itself never calls forth a secretion. Further, it is a daily occurrence to find in the stomach of the dog thick rolls of hair, and yet their presence in no way hinders the arrest of the secretion, which occurs when digestion has ceased. Such an occurrence would have been specially obvious in our dog with the isolated stomach, since it was bedded with sawdust in order to guard against maceration of the wound by juice trickling out. Very often we found enormous quantities of sawdust in the stomach, as much as half a pound weight; obviously the dog had licked the wound from adherent sawdust, which it then swallowed, together with that sticking to its nose. And yet these particles of sawdust of themselves, which certainly acted as mechanical stimuli, never caused a secretion. It appears to me that this long series of facts ought to suffice to carry the supposition to its grave that by direct mechanical stimulation one is able to set the neuro-secretory apparatus of the stomach into activity. And yet the feather and the glass tube continue the even tenor of their ways to this moment and function in some text-books, yea, even in articles which specially treat of gastric secretion as exciters of the gastric glands. There are, it is true, a few physiologists who hold mechanical stimulation, in relation to gastric secretion, not to be very effective, and give it a subordinate position in the series of exciting agencies, but as yet I know of no other physiologist who has wholly denied its influence, and who has not held it possible to obtain at least some juice by it.