ORGANS OF RESPIRATION.
The lungs are supplied with air through the larynx and the trachea.
The larynx is an irregular cartilaginous tube, forming the upper part of the windpipe, as the whole tube is commonly called.
The larynx is situated immediately below the root of the tongue, and forms the protuberance in the front part of the neck, called Adam’s apple.
The trachea, which is a continuation of the larynx, is composed of about eighteen cartilaginous rings, connected together so as to form a tube, which is capable of maintaining a uniform size. On entering the chest, the trachea divides into two trunks, called bronchi, one of which goes to the right, and the other to the left, lung. As soon as the bronchi enters the lungs they branch off into numerous divisions and sub-divisions; their ultimate extremities terminate in air cells.
The lungs occupy the greater part of the chest, the heart being the only organ of much volume, which it includes in it.
The chest, or thorax, is a cavity closed on all sides from the entrance of air, and its bony walls afford an admirable protection to the delicate organs included within it. The walls of the thorax are formed by the breast-bone in front, by the ribs and spine on the sides and back, and by the diaphragm below.
The diaphragm, as has been stated in a previous part of this chapter, is a large muscular partition, which separates the chest from the abdomen.
The explanations given in this chapter upon the arterial and venous circulation, also upon the names, places and relations of the abdominal and thoracic viscera, will be found of the utmost importance, to understand fully the process of embalming already given, and also the other methods which will be stated hereafter.
Although briefly enunciated, this review of the anatomy of the parts of the human body, which the embalmer must be conversant with, will be found quite sufficient for the purpose.
It will be seen, that even after the arterial and venous systems have been properly injected, there still remains a prolific source of putrefaction in the liquids contained in the intestines, and the thoracic viscera; for instance, the fecal matter contained in the intestines, and the undigested food in the stomach at the time of death, must all be evacuated, and the organs containing them properly cleaned and injected, and unless this be done fermentation will set in, and be followed by rapid decay of the surrounding tissues. It is true the arteries and veins extend their branches to all parts, and to every organ of the body, but it is also an undeniable fact that the contents of those organs which are prone to putrefy will carry the infection to the vessels containing them.
The stomach and bowels are emptied of their contents for the mere reason that these same contents are already undergoing a process of fermentation, which will generate into rapid decay and the emission of noxious gases.
In certain cases of consumption, the lungs are gangrenous and decayed long before death takes place; it will then be found necessary to introduce through the trachea some antiseptic fluid which will stop the progress of decay.
It is also necessary that the names of the different organs mentioned in this work should be explained, so as to make the use of technical words comprehensive to every undertaker who is not supposed to be familiar with the terms of the dissecting room or the human organism in general.
Besides the knowledge of the information given in the preceding pages will enable the embalmer to follow the workings of the embalming process in all its details, and enable him to discover the causes of failure in certain cases; also to use the proper means in the achievement of success.