=The lesions= are those of acute gastro-enteritis—congestion of the mucous membrane, abomasum, and intestine, submucous infiltration, shedding of the epithelium, which sometimes attains the stage of ulceration, suffusion and intestinal or superficial hæmorrhage, dilatation of the capillaries, etc. The symptoms of poisoning are produced by the absorption of toxic products, which pass from the intestine into the blood current. Poisoning is frequently complicated by infection produced in a similar manner. =Treatment.= The first point is to change the food. This alone is often sufficient to dispose of the digestive disturbance in a week or two. In addition, mustard plasters may be applied, and purgatives, stimulants and mucilaginous drinks may be given. Finally, diuretics are useful in eliminating the toxic products accumulated in the blood. They comprise general stimulants like wine, alcohol, tea, coffee, etc. Subcutaneous or intravenous injection of physiological salt solution is indicated. POISONING BY CAUSTIC ALKALIES. =The cause= consists in the administration of insufficiently diluted solutions of ammonia in cases of tympanites, or the ingestion of quick-lime, used for disinfecting stables, by animals suffering from depraved appetite. =The symptoms= indicate injury to the anterior part of the digestive tract. They consist in salivation, loss of appetite, colic, indigestion, diarrhœa, and progressive loss of strength. =Diagnosis= is only possible when the history is clear. =The prognosis= is grave if the doses swallowed have been so large as to cause severe burning of the mouth, œsophagus, rumen, etc. The local lesions are grey and soft. =Treatment= consists in immediately giving acidulated draughts containing vinegar or 1, 2 or 3 per cent. of hydrochloric acid, and emollient, mucilaginous drinks containing opium for the purpose of calming the irritation. POISONING BY CAUSTIC ACIDS. Cases of this kind are rare. Gerlach described a case of poisoning by straw which had been removed from sulphuric acid carboys. Abadie saw a number of cases which were traced to the unskilful treatment of two empirics. =The symptoms= point to the existence of stomatitis, œsophagitis, and gastro-enteritis. Death occurs rapidly, with a running-down pulse. On post-mortem examination one discovers more or less deep burning of the mucous membrane of the digestive tract. =The diagnosis= is difficult in the absence of information. =The prognosis= is grave. =Treatment= comprises administration of alkaline draughts, solutions of bicarbonate of soda, calcined magnesia, etc., and of mucilaginous drinks containing opium, chalk, etc. This may produce temporary relief. Water mixed with whipped whites of eggs is also extremely valuable, but it is often better to slaughter the animal as soon as the condition is diagnosed. POISONING BY COMMON SALT.