_Cure._--Fomentations of marshmallows; a light diet of scalded shorts; an occasional drink of thoroughwort tea. These with a little rest, in a comfortable barn, will perfect the cure. _Remarks._--If any irritating substance is suspected to have fallen into the ear, efforts must be made to remove it: if it cannot be got at, a small quantity of olive oil may be poured into the cavity; then, by rotating the head, with the affected ear downwards, the substances will often pass out. SEROUS MEMBRANES. These membranes derive their name from the serous or watery fluid they secrete, by which their surface is constantly moistened. They are to be found in the three cavities of the chest; namely, one on each side, containing the right and left lung, and the intermediate cavity, occupied by the heart. The portion of the membrane lining the lungs is named the _pleura_, and that lining and covering the heart is called the _pericardium_. The membrane lining the abdomen is named the _peritoneum_. The ventricles of the brain are also lined by this membrane. The serous membranes, after lining their respective cavities, are extended still farther, by being reflected back upon the organs enclosed in their cavities; hence, if it were possible to dissect these membranes from off the parts which they invest, they would have the appearance of a sac without an opening. In the natural state, these membranes are exceedingly thin and transparent; but they become thickened by disease, and lose their transparency. The excessive discharge of fluids into cavities lined by these membranes constitutes the different forms of dropsy, on which we shall now treat. DROPSY.