=(b) Motor Dyspepsia.= Finally, it would appear that general bad health, abstinence and exhausting work, may produce a form of dyspepsia, unconnected with secretory disturbance, but resulting from mechanical disturbance due to general enfeeblement and to atony of the muscular walls of the gastric compartments. The rumen ceases to perform its work of mixing the food, the reticulum also acts badly, and the abomasum receives imperfectly prepared material. The result is what might be described as motor dyspepsia, in opposition to those forms which are of chemical origin. The condition may vary in degree, peristalsis being diminished (one contraction every two or three minutes instead of two per minute), or being simply intermittent and occurring only for a few hours during the day, or finally being altogether suppressed. Suppression is never absolute, but atony may be so marked that the mixing of the food is very imperfectly performed. =Symptoms.= The most constant symptom present in all dyspeptic conditions is chronic tympanites, indicated by a certain degree of tension or by permanent dilatation of the rumen. Rumination is impeded and irregular, the distended rumen loses its power of contraction, and no longer causes eructation nor passes gas into the intestine. It becomes progressively inert, whether the inertia be primary and occur suddenly, as a result of some particular condition of the sympathetic system (motor dyspepsia), or secondary and of slow development in consequence of disturbance in the gastric secretions and of abnormal organic fermentation (secretory dyspepsia). This symptom of tympanites is always accompanied by irregularity, diminution, and frequently also by depravity of appetite. Wasting occurs, but to a very varying degree, according to the nature of the primary condition and the method of feeding. These general symptoms are accompanied either by constipation or by diarrhœa; and as stagnation of food leads to fermentation, which always forms products differing from those of normal digestion—toxic materials in fact—a chronic auto-intoxication results, which in its turn, if not remedied, becomes a cause of irritation, and aggravates the bad general condition. In many cases fever is absent, except during the final complications, in animals in the last stages of wasting; but some signs always exist on which the diagnosis may be founded. The most frequent clinical type of these dyspeptic conditions is motor dyspepsia, consisting in relative atony of the rumen without disturbance in the secretion of the gastric mucous membranes. Luckily, this is the most easily curable form, and is only marked by distension, dulness and constipation. Dyspeptic diseases of secretory origin are little understood. Their essential causes have been badly described, and their clinical symptoms are ill-recognised.