In the examination of the _body-cavities_ and _hollow organs_, as well as _pathologic hollow structures_, the first thing to note is the escape of gas or air under pressure. Occasionally it is best to open the organ under water to note the escape of bubbles. The odor of the gas, inflammability, etc., are to be noted. The fluid or solid contents (blood, bile, urine, féces, mucus, pus, exudates and transudates, altered secretions, food-remains, concretions, foreign bodies, parasites, etc.) are described as to their amount, color, consistence, odor, reaction, chemical nature, precipitate, presence of cellular elements, etc. The size of the cavity, monolocular or multilocular, the character of its lining (transparency, translucency, cloudiness or opacity, color, “shine,” moisture, smoothness, roughness, villous or polypoid, consistence, thickening, swelling, elevations, atrophy, incrustations or deposits on the lining, etc.) are to be considered. In the case of cystic tumors (adenocystomata, dermoid cysts, cholesteatomata, etc.) especial attention should be paid to the character of the cyst-contents (mucoid, glairy, colloid, jelly-like, pea-soup-like, pultaceous, mushy, doughy, caseous, pearly, laminated, flaky, powdery, etc.). CHAPTER IV. THE EXTERNAL EXAMINATION. =THE BEGINNING OF THE AUTOPSY.= The autopsy begins with the examination of the exterior of the body. The cadaver should be completely stripped of clothing and examined as a whole, then as to its separate parts. Time is saved and omissions prevented if a definite order is followed in the external examination, such as follows here.