Two studies were reported in which rats with hypothalamic cannulae were injected with carbachol. All animals exhibited drinking following injection. In the first study, this was demonstrated both prior to and following a series of test sessions, and in the second study, at the end only. During the test sessions themselves, only food was available. Animals displayed no tendency to increase their food intake upon carbachol administration during the 16 test sessions. This was contrasted with the ease with which such shifts have been demonstrated with electrical stimulation and suggests a specificity of function that can be detected with chemical but not electrical stimulation.