Cavity

“ In any single act of inspiration the mouth is opened, and the oral cavity enlarged by the lateral expansion of its walls. When the oral cavity is filled with water, the mouth is closed and the expiratory process begins. By the lateral contraction of the oral walls the water is driven outwards through the gill-clefts, and over the gill-lamellae. During this process the branchial arches become widely separated by the contraction of their muscles, the operculum is elevated, and the oesophagus is closed by the contraction of its muscular wall. ”

“ These two sections of the body cavity, which in Amphibia and Sauropsida remain in free communication with the undivided peritoneal cavity behind, may, from the fact of their containing the lungs, be called the pleural cavities.
In Mammalia a further change takes place, in that, by the formation of a vertical partition across the body cavity, known as the diaphragm, the pleural cavities, containing the lungs, [Pg 632] become isolated from the remainder of the body or peritoneal cavity. ”

“ The cavity of the mouth is actually larger than that of the body, thorax and abdomen together. The upper jaw is very narrow, but greatly arched from before backwards, to increase the height of the cavity and allow for the great length of the whalebone-blades ”

“ In addition to forming the organs, the tissues are also grouped in such a manner as to provide supports for organs and to form cavities in which organs are placed. The various cavities of the body are of particular interest and importance. The three largest ones are the cranial cavity, containing the brain; the thoracic cavity, containing the heart and the lungs; and the abdominal cavity, containing the stomach, the liver, the intestines, and other important organs (Fig. 2) . Smaller cavities serving different purposes are also found.
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“ In the instances in which the heart arises as a double cavity it is formed before the complete closure of the throat, and in those in which it arises as a single cavity it is formed subsequently to the complete formation of the throat. ”

“ He describes accurately (p. 226 and table xvi.) the cavity in the superior maxillary bone, to which his attention was drawn by a lady patient, in whom an abscess of this cavity, ever since known as the antrum of Highmore, was drained by the extraction of the left canine tooth. He became a magistrate for Dorsetshire, and attained considerable practice as a physician. ”

“ It is painful, tender, advances rapidly to maturity, becomes conical, and finally bursts and discharges bloody "matter." Through the opening, and filling the cavity, may be seen a piece of sloughing cellular tissue which is called the core. ”

“ This single cavity and its lining serve apparently for all those functions (digestion, excretion, circulation and often reproduction) which in more complex organisms are distributed among various cavities of independent and often very diverse origin. ”

“ Fabricius enumerates various conveniences arising from this cavity, according to its dimensions. I shall be brief on the subject: it contains air, and is therefore useful in the ventilation of the egg, assisting the perspiration, refrigeration, and respiration, and finally the chirping of the chick. Whence this cavity, small at first, is larger by and by, and at last becomes of great size, as the several offices mentioned come into play. ”

“ The mouth is at the hinder end of a depression called the buccal cavity, and is surrounded by an annular tumid lip, raised into papilliform ridges and bearing a few spines (Fig. 3) . Within the buccal cavity are the two jaws. They are short, stump-like, muscular structures, armed at their free extremities by a pair of cutting blades or claws, and are placed one on each side of the mouth. In the median line of the buccal cavity in front is placed a thick muscular protuberance, which may be called the tongue, though attached to the dorsal instead of to the ventral wall of the mouth (Fig. 3) . ”

“ In young teeth, he says, the dental cavity is very large, in proportion to the size of the tooth. According to some anatomists, the central cavity of a tooth is coated by a very soft and thin membrane, formed by a tissue of very small vessels and nerves; and besides, this cavity is filled with marrow, like hollow bones. The observations of the author, however, do not agree with these statements. The dental cavity does not contain any fatty substance analogous to the marrow of bones. As to the above-mentioned membrane, Eustachius doubts its existence. ”

“ In man and the other mammals (but only in these) this cœloma divides, when fully developed, into two different cavities, which are separated by a transverse partition—the muscular diaphragm. The fore or pectoral cavity (pleura-cavity) contains the œsophagus (gullet) , heart, and lungs; the hind or peritoneal or abdominal cavity contains the stomach, small and large intestines, liver, pancreas, kidneys, etc. ”

“ In shipping a body, cavity embalming must always be resorted to and consists of introducing a trocar into the abdominal and thoracic cavities and injecting sufficient fluid over the contents of these cavities to thoroughly preserve them. ”

“ When the aforesaid means of cure—that is, the mouth washes and the filling—are of no use, Guy advises the margins of the carious cavity being taken away with a scalpel and file, so that alimentary substances may not be retained inside it. ”

“ The teeth.—Imperfect use of the teeth leads to many ills. When adequately exercised and made to execute for one or two hours every day a lively dance in their sockets, during which the circulation of blood and lymph in the tooth-pulp, periodontal membrane, and surrounding tissue of the gum is vigorously stimulated, and the cavity of the mouth is bathed in a copious flow of salivary and other buccal secretions, we have conditions which make alike for the health of the buccal mucous membrane, of the teeth, and of the periodontal membrane and alveoli ”

“ The cavity of the stomach is only the size of the amount of food present; in other words, the food exactly fills the cavity. The motor nerve fibres to the stomach run in the vagi, which also contain fibres inhibitory to the cardiac sphincter. ”

“ Again, when the dentist excavates a small cavity in one of our teeth, we feel the hard point of his instrument scraping, in distinctly differing directions, a surface which seems to our sensibility vaguely larger than the subsequent use of the mirror tells us it 'really' is. ”

“ That the mouth cavity really can act as a resonance-chamber can be easily demonstrated by holding a small vibrating tuning-fork before the open mouth, and varying the shape and size of the cavity till the sound of the fork is observed to be suddenly increased in volume. ”

“ In the chambers of the eye, water, as being a product of digestion, is constantly secreted; the orbitar cavity is a mouth with salivary glands, giving tears; the lachrymal canal is a bronchial duct, which opens into the nose like the Eustachian tubes did from the ear into the mouth; the eye-lids correspond to the lips, and are, in like manner, fringed with hairs; indeed, this little organ repeats in itself the whole of man, which is the highest and most complete organization. ”

“ This cavity is the gastral or digestive cavity, and it opens to the exterior through a wide vent or osculum at the upper extremity of the sponge. The thin wall is also pierced by numerous small inhalant pores or prosopyles. The inhalant pores, the gastral cavity and the vent constitute the canal-system, through which a stream of water can be kept flowing by the activity of the collared cells which line practically the whole of the gastral cavity. ”

“ The axis of the cavity represents a curve, which corresponds very nearly with the curve of the sacrum, the extremities being indicated by the central points of the inlet and outlet. A knowledge of the direction of these axes is most important to the surgeon, as indicating the line in which instruments should be used in operations upon the viscera of the pelvis, and the direction of force in the removal of calculi from the bladder; and to the accoucher, as explaining the course taken by the fetus during parturition. ”

“ The little visceral cavity contains the complex groups of muscles for opening and closing the valves, a simple stomach, a large granular liver, a short intestine, two hearts, and the centre of the nervous system. ”

“ Collect a further sample of blood or serum for subsequent investigation as to the presence of antibodies.
Peritoneal Cavity.—
16. Sear a broad track in the middle line of the abdominal wall; open the peritoneal cavity by an incision in the centre of the seared line. Observe the condition of the omentum, the mesentery, the viscera and the peritoneal surface of the intestines.
17. Collect a specimen of the peritoneal fluid (or pus, if present) in a capillary pipette. Make cultivations, tube and surface plate, and cover-slip preparations from this situation. ”

“ Plugging cavities, either with gold or tinfoil, of good quality, should never be neglected. Carefully remove all rotten portions; thoroughly cleanse and dry by means of cotton; then introduce the metal gradually, pressing it into all parts of the cavity with as much firmness as possible, until it becomes a solid mass with the exterior surface, even and smooth. ”

“ In the Cœlenterata no body cavity as distinct from the alimentary cavity is present; but in the remaining Invertebrata the body cavity may (1) take the form of a wide space separating the wall of the gut from the body wall, or (2) may be present in a more or less reduced form as a number of serous spaces, or (3) only be represented by irregular channels between the muscular and connective-tissue cells filling up the interior of the body. The body cavity, in whatever form it presents itself, is probably filled with fluid, and the fluid in it may contain special cellular elements. ”

“ It is possible also that the same larvæ which are free in the oral cavity when the food is being eaten migrate into the nasal cavities. After being stationary a fresh skin is formed and the spine-bearing cuticula are thrown off. ”

“ There is infection; therefore, the first thing to do is to remove the pus.
Dental Treatment.—If there is a large cavity in the tooth, try to enter the root canals and remove the putrescent matter. If the face is badly swollen, make a digital examination, and over the root of the affected tooth you will find a spot about the center of the swelling where it seems to be spongy, appearing to hold the impress of the finger. Take a clean, sharp, cycle-shaped lancet, place on the spot, holding the patient’s head firm with your other arm for fear of his moving. ”

“ In several of the types with a well developed body cavity it has been established that this cavity originates in the embryo from a pair of alimentary diverticula, and the cavities resulting from the formation of these diverticula may remain distinct, the adjacent walls of the two cavities fusing to form a dorsal and a ventral mesentery. ”

“ Then also the air passes no longer through the mouth, but through the nose, as being the peculiar opening of the thoracic cavity in the head. Even the Fishes have as yet no nostrils opening into the mouth. ”

“ The first step towards the preparation of the mouth [Pg 270] for dental operations is the removal of calculus and decayed fangs. Let this be done in a manner that will insure future cleanliness, where the proper after attention is given on the part of the patient.
As regards the preparation and filling of cavities, there are so many conflicting conditions, that we must be governed entirely by the case before us; but to be thorough in our preparation, we must so shape the cavity as to have the walls nearly plumb, uniform margin, slightly undercut. ”

“ Those, that are seated in the eyes, or in the gums, the nostrils or the exterior angle of the eye, or in the cavity of the ears, abdomen or the umbilicus, or about any suture of the body, hips, ribs, arm-pits, chest, breasts, sides, or the joints, as well as those, that secrete frothy blood or pus with a gurgling sound, or contain any foreign matter embedded in their inside, are healed only with the greatest difficulty. ”

“ That portion of the trunk which in man commences beneath, and in mammalia behind, the diaphragm, and terminates at the extremity of the pelvis. The abdominal cavity is the largest in the human body. It is lined with a serous membrane, called the peritoneum. ”

“ Soft mucous polypus may exist for many years, without depressing the palate, or projecting into the fauces. The anterior nasal cavity is its most frequent seat, and it widens and fills up the fissure between the anterior and posterior cavities: frequently it projects backwards, but is not visible, though it may be felt with the finger behind the soft palate. Its growth is slow. ”

“ This regularity is found too only in the human skeleton. The animals are irregular men. (Vide Oken's Zahlengesetz in den Wirbeln. Isis, 1829, S. 306.)
Cavities of the Trunk.
2115. The osseous system forms the trunk or body, because it follows the vascular system; the two other galvanic systems, the dermal and intestinal systems, form the large portions of the trunk or its cavities; to them is added the sexual cavity or pelvis.
2116. There are thus three truncal cavities, a pulmonary, an intestinal, and a sexual cavity, or thoracic, abdominal, and pelvic cavity. ”