Dr Beaumont did not think of following it up by a regular series of experiments, to ascertain the effects of cold and hot drinks on the progress of digestion and on the general system. It is well known, for example, that a copious draught of cold water, taken in a state of perspiration and fatigue, is often instantly fatal; but its operation has never been satisfactorily explained. The above experiment, however, throws some light on it; for if a single gill of water at 55° (which is not by any means a low temperature) is able to reduce the heat of the stomach in a moment by no less than _twenty-nine degrees_, when neither fatigue nor perspiration is present to add to its effect, the influence of a _large quantity_, such as is usually drunk by harvest-labourers and others who die of it, and at a still lower temperature, must undoubtedly be much more powerful and permanent, especially when the bodily energies and means of resisting the shock are impaired by previous labour and exhaustion under a burning sun. In these cases the shock necessarily arising from such a sudden and extensive fall of temperature is greatly increased by the position of the stomach in the very centre of the vital organs, to all of which it is most intimately linked by the numerous nervous connexions given for the express purpose of extending the range and direction of its sympathies. Keeping in mind the great depression of temperature caused by swallowing so small a quantity of cold water, and also the ascertained fact that a heat of about 100° is requisite for healthy digestion, we shall have no difficulty in accounting for the frequent injurious consequences arising from considerable quantities of ice-cream being hastily eaten, as they often are, at the end of a substantial dinner. The immediate effects of the rapid abstraction of heat to which they give rise in the stomach, are the instantaneous contraction and diminished action of its bloodvessels, the consequent stoppage of the gastric secretion, diminished sensibility of its nerves and muscular fibres, and, lastly, disturbance of the heart and neighbouring vital organs, both by sympathy and by the direct abstraction of their heat. Such, at least, are the consequences which flow from the application of cold to parts exposed to observation, and partially verified by Dr Beaumont in the case of the stomach; and if the analogy holds throughout, as there is every reason to believe, we cannot wonder that the free use of ice-cream at the end of a good dinner or supper should retard and even arrest digestion in a person delicately constituted.