If dysentery continue to advance it will terminate fatally within a fortnight. Death is generally preceded by the "_black scour_," which is only an aggravation of the purging, the stools being mixed with shreds of dark gangrenous matter from the decomposed interior of the intestines. (136.) _Causes of Dysentery._ Many absurd opinions have gone abroad regarding the contagious nature of this affection. Contagion, however, has nothing to do with the matter, the spread of the disease depending entirely on the state of the atmosphere and the nature of the locality. When dysentery occurs the weather is usually sultry, the ground upon which the flock has been going, foul, and the management of the sheep so improper, as to be sufficient of itself to produce the disease very generally. There is in fact only one proof of a disease being infectious, viz., its immediate occurrence on the introduction of an affected animal among such as are in good health, on sound food, and in easy circumstances. This proof, however, in regard to dysentery has never been established, and no medical person will now affirm that it is contagious. Some think that it travels from flock to flock in the direction of the wind, but its appearing simultaneously in many folds ought rather to be charged to the fact of the predisposing causes being nearly similar in all. (137.) _Treatment of Dysentery._ Bleed freely if the disease has continued only for a few days, but moderately if a longer time has unfortunately elapsed. Stoving, by which is meant shutting the animal in a wash-house, and allowing the apartment to become filled with steam, though urged by some writers, cannot here be recommended. The intended object is the promotion of perspiration, by exciting the action of the skin, but this may be brought about by means much more conducive to the safety of the animal. After the bleeding immerse the sheep in a tub of hot water, and retain it there for twenty minutes; then administer an ounce of Castor oil, with thirty drops of Laudanum, and cover the sheep up in a snug corner. After the oil has operated, thin well-boiled flour-porridge, given at intervals, in small quantities, will help to defend the ulcerated bowels, sooth the pain, and stop the purging. If these fail, you may use the astringent mixture recommended in diarrhoea at page 175, and in the same manner, adding to each dose a grain of ipecacuanha. When the appetite returns, and the stools begin to acquire consistency, speedy recovery may be prognosticated. During recovery part of the wool always falls off. (138.) _Prevention of Dysentery._ If you wish your sheep to take the disease, do as some wiseacres recommend--put tar upon their tails, and noses; you will thus render them feverish, and uncomfortable, and every way fit for an attack.