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GASTRIC JUICE.-PANCREAS. INTESTINES.-KIDNEYS.
The GASTRIC JUICE is said to be of so powerful a nature, that after death the stomach is occasionally eaten into holes by its action. And it is also said, that if exposed to a proper temperature, it will digest food in metal tubes.
The PANCREAS, or SWEET-BREAD, is a large gland of the salivary kind, of a long figure, compared to a dog's tongue. It lies across the upper and back part of the abdomen, under the stomach. Its use is to secrete a juice called the pancreatic juice, which appears to be similar in its properties to saliva, and together with the bile helps to complete the digestion of the aliment. It communicates with the duodenum.
The INTESTINES consist of that convoluted tube beginning at the right orifice of the stomach called pylorus, and ending with the sphincterrecti. The length of this canal is generally six times the length of the whole human subject. It is divided by nature into two parts. The small intestines begin from the stomach, and fill the middle or fore part of the abdomen; the large intestines occupy the sides, and both the upper and lower parts of the same cavity.
The KIDNEYS are shaped a kidney-bean. They are situated on the lower part of the back, one on each side. They are generally surrounded with more or less fat.
The SENSES are those faculties or powers by which external ob. jects are perceived. The sight, touch or feeling, hearing, smell and taste, are called the senses. The organs through which they operate are the following:
The EYE is the organ of seeing. The eye-lids, the eye-lashes, and the eye brows, require no particular description. The eye-ball is of a globular figure; it is composed of various membranes; but those pirts of the eye deserving the most notice, are the iris, the pupil, and the retina. The iris is that'colored circular ring situated beneath the crystalline lens, which surrounds the central or dark part called the pupil. It is capable of expanding or contracting, which it constantly does, according to the quantity of light which is thrown upon the eye. In a very bright light the pupil is reduced by the contraction of the iris to a very narrow hole; in a dark place the pupil is so much enlarged, as to render the iris scarcely visible. The pupil is the dark round opening in the mlddle of the eye, surrounded by the iris, and through which the rays of light pass to the retina, which is the true organ of vision, and is formed by an expansion of the pulp of the optic nerve. Externally the globe of the eye and the transparent cornea are moistened by a fluid called the tears, which are secreted in the lachrymal glands, one of which is situated above each inner corner of the eye. In proportion as the eye is more or less round, is the sight of a person longer or shorter. Persons of short sight are called myopes, of long sight, presbyopes.
TOUCH, or FeeLING, resides in every part of the body that is supplied with nerves. The sense of touch is most exquisite in the lips, the tops of the fingers, the tongue, and a few other places.
The EAR is the organ of hearing. In man it consists of an external ear, or auricula, and an internal bony cavity with numerous circular and winding passages, by which the vibrations of the air are collected
and concentrated, and by a peculiar mechanism conveyed to the auditory nerves. The ear is supplied with peculiar glands, which secrete an unctuous substance, called the way of the ear. The external auditory passage proceeds in a spiral direction to the tympanum or drum of the ear, which forms a complete partition between this passage and the internal cavities. Beyond the tympanum is a hemispherical cavity which leads to the fauces, or opening at the back of the mouth: this opening is of a trumpet form. The inner cavity, including the wind. ing passage, is aptly called the labyrinth of the ear. The sense of hearing is perhaps still more important than that of seeing; but as we can have no just conception of the real state of social existence without either of these senses, it is idle to speculate on such comparisons.
The NOSE is in man, and most of the superior animals, the organ of smelling. The structure of the nose has nothing in it so very peculiar that can convey any idea of a mechanical organization to aid the sense of smelling. It is true, the nerves of the nose are considerably expanded over the nostrils, and are defended from external injuries by a peculiar mucus; but it is very difficult to ascertain what are the es. sential organs of smelling. The nostrils are two passages of the nose which communicate interiorly with the upper part of the mouth. The use of the nostrils is for smelling, respiration, and speech. The nose is an important part of the human countenance; it is considered in almost all countries as one of the features to which peculiar merit is attached.
The TASTE resides chiefly in the tongue, in conjunction with the palate, lips, and other parts of the mouth. The tongue is however destined to perform much more varied and important functions than that of conveying to the mind the taste of sapid bodies. It is the tongue, in conjunction with the lips, teeth, palate, and throat, which produces the sounds of language. The tongue is partly muscular, and partly composed of membranes and cellular substance. Its upper side is covered with papillæ, in which the taste more immediately resides. The impression of sapid bodies on the organs of taste is modified by age, size, habit, and the more or less frequent application of strong stimulants. The state of the stomach, as well as general health, is often indicated by the state and color of the tongue. In health the tongue is always of a red color; in disease it varies from white to yellow, and sometimes is almost black. In health the tongue is always more or less moist; in disease frequently parched and dry ; this last condition is, however, produced in health by the mere absence of moisture, evinced by the sensation we call thirst.
The SEXES differ by obvious indications; but there are some not so universally recognized, which we may mention. The male is generally of a larger size than the female, and more robust; the male becomes frequently bald on the top of the head, the female rarely or never; the male has always more or less beard, the female rarely any, except as old age approaches, and then it is chiefly confined to the upper lip. The anatomical differences, besides the obvious ones, are, in the female, a larger pelvis than in the male, more delicate muscles and smaller bones; and the phrenologists say, that the female skull is more elongated than the male, from the protuberance in the middle of the
back part of the skull, (which they denominate philoprogenitiveness, or love of children,) being more prominent. The mental differences of the two sexes are also important; women appear to possess more imagination and less judgment than men; these differences are unfortunately too often widened by mistakes in the education of the female mind.
ON THE MIND AND ITS FACULTIES,
The term MIND has been lately applied by philosophers to the intellectual portion of man, as being a more correct term than either soul or understanding. It implies that part of our being which is occupied in thought. The seat of the mind is manifestly the brain : but in what part of it, whether the whole, or in the pineal gland, as Des Cartes maintains, where he says all the nerves terminate ; or whether, as Soemmering states, the fluid contained in the ventricles of the brain be its seat, is unknown : all such opinions being mere conjectures.
The mind, or soul, has been usually divided into a certain number of faculties. We shall consider it from its more simple to its more complex state. The commonest and simplest impression made upon the mind being conveyed to it by either of the senses, is called
SENSATION. Sensation is either pleasurable or painful; in proportion to the degree of pleasure or of pain produced by a sensation, will be the vividness of its apprehension by the mind. An apprehended sensation is termed PERCEPTION : that is, when the mind itself perceives, recognizes the sensation,—when it becomes the subject of thought in the mind, it is then called perception. An idea is a resemblance or image of any thing, which, though not seen, is conceived,apprehended by the mind ;-an idea appears to be, therefore, nothing more than a well-defined and apprehended perception. An idea may be simple or complex, true or false. Simple ideas are those which arise in the mind from sensation; as those of color by the eye, of sounds by the ear, heat by the touch, &c.; some ideas are formed by sensation and reflection jointly, as pleasure, pain, power, existence. Complex ideas are infinite; some are not supposed to exist by themselves, but are considered as dependencies on, or affections of substantives, as, triangle, gratitude, murder, &c. Combinations of simple ideas are such as, a dozen, a score, beauty, theft, &c. The association of ideas, and consequently of affections, is one of the most important characters of the human mind, and the great source of our happiness or misery.
In tracing the process of the human mind in acquiring knowledge, we observe the following curious analogies or gradations; it commences with a simple idea or thought impressed, which is connected with simple perception. This solicits attention, which, according to its degrees of importance, disposes to observation, consideration, investiga
tion, contemplation, meditation, reflection. These voluntary operations of the mind are necessary to the formation of clear conceptions, right understanding, an enlarged comprehension of some subjects, nice discernment, and accurate discriminations concerning others: these acquisitions enable us to abstract essential qualities in our minds from the subjects in which they are seated, to assemble others in new combinations, to reason, to draw inferences, and, finally, to judge or decide on their merits or defects.
MEMORY is that quality of the mind by which it is enabled to call up, generally at will, and upon suitable occasions, ideas, trains of thought which have been previously impressed upon it. No intellectual process can be carried on without memory: where the memory is weak, there the intellect will be found weak; where the memory is good, there, in general, will the intellect be powerful. In nothing, however, do individuals differ more from each other, than in their memories. Some remember one kind of facts and things well, while others remember them very indifferently. This has been attributed by the phrenologists to the activity and size of particular organs in the brain; and it seems to us probable that there may be some truth in this,-indeed the phrenologists assign to the memory many organs of the brain, such as those of form, size, weight, color, space, order, time, number, tune, language. But whatever truth there may be in this, we believe that more depends upon the exercise of the mind in any given course, than on the original conformation; that, in order to make the memory efficient, it must be often exercised on any given subject; and that the most important knowledge, if not occasionally revived by repetition, will frequently vanish from the mind. The notion of the mind being a storehouse, and that ideas once deposited there, will always there remain, is extremely fallacious. It is true they frequently do so, especially those received in youth ; but many of these, without repetition, become in time obliterated. Hence, therefore, the necessity of not only the processes of Education to improve the memory, but of an occasional repetition of them, in order that they may be efficient and useful to us in after life.
Recollection is that part of the memory, which consists in calling up in the mind the knowledge, which has been previously impressed upon it. Atlention and repetition help much to fix ideas in the memory; the ideas which make the most lasting impressions are those accompanied hy pleasure or pain.
The powers of memory of some persons for particular subjects are astonishingly great. Seneca says that he was able, by the mere effort of his natural memory, to repeat two thousand words upon once hearing them, each in its order, though they had no connexion with each other. He also mentions that Portius Latro retained in his memory all the declamations which he had ever spoken, and never found his memory fail in a single word. Cyneas, ambassador to the Ronians from king Pyrrhus, had, in one day, so well learned the names of his spectators, that on the next he saluted the whole senate and all the populace assembled, each by his name. Pliny says, Cyrus knew every soldier in his army by name, and L. Scipio all the people of Rome. Carneades would repeat any volume found in the libraries as readily as if he were
reading. Many modern instances of the great powers of memory might be also adduced, but they do not appear necessary.
IMAGINATION is that particular state or disposition of the mind by which it is enabled to form numberless new and extraordinary ideas which are not the immediate result of external impressions or of recollection, and hence is obviously distinguished from perception and memory. By the imagination an individual creates thoughts entirely his own, and which never might have existed had they not occurred to the individual mind. The exercise of most of the other qualities of the mind requires calmness and composure. · The imagination delights in the most heterogeneous and incoherent combinations and most extravagant circumstances. These visions or phantoms are nevertheless sometimes impressed upon the memory, and during imperfect or disturbed sleep present themselves and produce those absurd combinations which occur in dreaming. Although the flights of imagination are bold, yet they conform in some degrce to the impressions which real objects have made upon the sensorium. And hence all the ideas which it calls up have some relation to prior received facts, and to the knowledge acquired by the mind.
Fancy, conceils, and phantoms, are merely species of which the imagination is the genus. Poets and printers are notoriously ihe subjects in which a powerful imagination is essential to the effectual developements of their respective arts.
GENIUS is, in numerous instances, allied to the imagination. It consists in that natural talent, disposition, or aptitude, which one man possesses of performing something in preference to another, with peculiar facility and excellence. Thus men are said to have a genius for painting, poetry, music, &c.; meaning, that the powers of their minds enable them to excel in those particular departments. Although, perhaps, minute attention to the genius of each individual is not, in a social and moral view, necessary in the education of youth, we believe, nevertheless, that some attention to this subject is absolutely necessary in order to effectuate the best developement of the character. And while we cannot avoid admiring genius, we ought never to forget that its best exemplification is when combined with moral, tisoful, and vir. tuous actions; that true genius, real science, and rational religion, ought to be inseparable companions.
REASON; that process of the mind by which different ideas or things are compared, their fitness or unfitness perceived, and conclusions drawn from such comparisons and perceptions. Judgment is a similar operation of the mind; but, as its name imports, it is that act of the mind by which it concludes and determines upon certain final results. Thus we compare the sun and the moon, and finding the sun greater than the moon, we determine or judge accordingly.
The WILL is a state or disposition of the mind, consisting in being disposed, willing, to do or avoid any act, or to obtain or avoid any thing. The state or disposition of the mind called the will, is produced by innumerable agencies. Some of these arise from the internal feeling of the mind itself; others from external objects, as heat, light, cold, human society; our affections, our hopes, our fears, our pleasures and