The Diaphragm is the powerful, dome shaped muscular structure, separating the chest from the abdomen.The diaphragm is so called because, like the diaphragm in a camera, it can pull itself tightly together becoming flattened, thus increasing the chest space and capacity of the lungs to expand on inspiration, when it relaxes, it curves upward into the chest again, thus helping to force the air out of the lungs in expiration.
As you can see, the diaphragm continually contracts and relaxes with the rhythm of inspiration and expiration.
Once in a while this muscle gets out of step with the respiration rhythm. It will then start contracting independently and at a faster rate, and will cause hiccups, belching, vomiting or sneezing.
This condition may be caused by reflex irritation of communicating nerve branches, as when dust or sharp odors irritate nerves in the nose , or when there is irritation in the gastrointestinal tract.
It may also be initiated by nervous states causing loss of nerve control, thus producing an attack of continuous hiccuping. No surgical operation should be performed to stop an attack of the hiccups. It can be stopped by medical means and even by household methods, and the operations, like most nerve-cutting operations, is not curative.
The diaphragm is attached in the front part of the abdomen at the end of the breastbone, and slants downward to the level of the lowest rib in the back, where it is attached to the spine.
The upper surface of the diaphragm is in contract with the lungs, or rather with the lung's outer, covering membrane, the "pleura", the lower surface comes in contact with the stomach in front, with the liver on the right side, spleen on the left and kidneys in the back.
The diaphragm has an opening in the center for the esophagus or feed pipe to pass to the stomach, and two openings in the back for the large blood vessels and nerves to pass from the chest to the abdomen.
If we call the head the "upper story" then the chest is the main floor, the abdomen is the basement, with the diaphragm as its ceiling, and the pelvis is the subcellar.
The subcellar (pelvis) contains the disposal plant of fluid and solid waste matter, the bladder and rectum, as well as the most important machinery, the sex organs, which keep and perpetuate the whole household, so do little-men think!