Fig. 88. A front view of the organs within the chest and abdomen. 1, 1, 1, 1, The muscles of the chest. 2, 2, 2, 2, The ribs. 3, 3, 3, The upper, middle, and lower lobes of the right lung. 4, 4, The lobes of the left lung. 5, The right ventricle of the heart. 6, The left ventricle. 7, The right auricle of the heart. 8, The left auricle. 9, The pulmonary artery. 10, The aorta. 11, The vena cava descendens. 12, The trachea. 13, The œsophagus. 14, 14, 14, 14, The pleura. 15, 15, 15, The diaphragm. 16, 16, The right and left lobe of the liver. 17, The gall-cyst. 18, The stomach. 26, The spleen. 19, 19, The duodenum. 20, The ascending colon. 21, The transverse colon. 25, The descending colon. 22, 22, 22, 22, The small intestine. 23, 23, The abdominal walls turned down. 24, The thoracic duct, opening into the left subclavian vein, (27.)

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CHAPTER XXIII.

THE RESPIRATORY ORGANS.

463. The nutrient portion of the food is poured into the left subclavian vein, (24, 27, fig. 88,) at the lower part of the neck, and is carried to the right cavities of the heart. The fluid in these cavities consists of the chyle incorporated with the impure blood. Neither of these two elements is fitted to promote the growth or repair the waste of the body. They must be subjected to a process, by which the first can be converted into blood, and the second freed of its carbonic acid gas and water. This is effected by the Respiratory Organs.

ANATOMY OF THE RESPIRATORY ORGANS.

464. The RESPIRATORY ORGANS are the Lungs, (lights,) the Tra´che-a, (windpipe,) the Bronch´i-a, (subdivisions of the trachea,) and the Air-Ves´i-cles, (air-cells at the extremities of the bronchia.) The Di´a-phragm, (midriff,) Ribs, and several Muscles, also aid in the respiratory process.

465. The LUNGS are conical organs, one on each side of the chest, embracing the heart, (fig. 88,) and separated from each other by a membranous partition. The color of the lungs is a pinkish gray, mottled, and variously marked with black. Each lung is divided into lobes, by a long and deep 210 fissure, which extends from the posterior surface of the upper part of the organ, downward and forward, nearly to the anterior angle of the base. In the right lung, the upper lobe is subdivided by a second fissure. This lung is larger and shorter than the left. It has three lobes, while the left has only two.