In the most urgent cases, however, relief must be obtained by _puncture of the rumen_, as a moment’s delay may mean death. The seat for such puncture is on the left side, at a point equidistant from the outer angle of the ilium, the last rib and the transverse processes of the lumbar vertebræ. Any part of the left flank might be adopted to enter the rumen, but, if too low down, the instrument might plunge into solid ingesta, which would hinder the exit of gas, and would endanger the escape of irritant liquids into the peritoneal cavity. In an extra high puncture there is less danger, though a traumatism of the spleen is possible under certain conditions. The best instrument for the purpose is a trochar and cannula of six inches long and ⅓ to ½ inch in diameter. (For sheep ¼ inch is ample.) This instrument, held like a dagger, may be plunged at one blow through the walls of the abdomen and rumen until stopped by the shield on the cannula. The trochar is now withdrawn and the gas escapes with a prolonged hiss. If the urgency of the case will permit, the skin may be first incised with a lancet or pen knife, and the point of the instrument having been placed on the abdominal muscles, it is driven home by a blow of the opposite palm. In the absence of the trochar the puncture may be successfully made with a pocket knife or a pair of scissors, which should be kept in the wound to maintain the orifice in the rumen in apposition with that in the abdominal wall, until a metal tube or quill can be introduced and held in the orifices. When the gas has escaped by this channel its further formation can be checked by pouring one of the antiferments through the cannula into the rumen. When the formation of an excess of gas has ceased, and the resumption of easy eructation bespeaks the absence of further danger, the cannula may be withdrawn and the wound covered with tar or collodion. When the persistent formation of gas indicates the need of expulsion of offensive fermentescible matters, a full dose of salts may be administered. If the presence of firmly impacted masses can be detected, they may sometimes be broken up by a stout steel rod passed through the cannula. If the solid masses prove to be hair or woolen balls, rumenotomy is the only feasible means of getting rid of them. In _chronic tympany_ caused by structural diseases of the œsophagus, mediastinal glands, stomach or intestines, permanent relief can only be obtained by measures which will remove these respective causes. CHRONIC TYMPANY OF THE RUMEN.