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diate use appears on dissection, and as we find that animals from whom it has been cut, live very well without it. But Mr. Cowper takes it to be a subordinate organ, ministering to the circulation. According to Dr. Boerhaave, the spleen receives the fresh arterial blood, prepares it in its glands, and pours it into its cells; mixes the humour thus prepared with the nervous juice, and more intimately unites them together.

The KIDNEYS are two glandular bodies, for separating the urine. They have arteries, veins, and

nerves.

The STOMACH is a large reservoir, for receiving the food, and retaining it until a certain change, called digestion, is produced. The capacity of the stomach varies from about 5 to 11 pints. It is divisible into 4 distinct layers or coats, called the external, muscular, nervous, and villous coats. Its structure is muscular, and this is necessary in order to propel the food when digested. From the inner surface of the stomach proceeds what is called the gastric juice, which is the chief agent in the digestion of the food..

The stomach communicates with the small intestines by means of a contracted ring, called the pylorus, which signifies, the keeper of the gate. This prevents the food from passing out of the stomach, before it has been sufficiently acted on by the gastric juice, which consists of water, albumen, common salt, and phosphoric acid. The gastric fluid acts independent of the stomach, and will digest food in metal tubes exposed to a proper temperature. It is a most powerful solvent, and acts on all substances indiscriminately, even on the stomach it. self, when unsupported by food. It is an antiseptic, and has nothing in it fermentative, as vulgarly sup posed. Artificial gastric juice may be made by macerating fresh flesh in a solution of culinary salt; hence the process of digestion has been called an animalizing solution.

CHYLE is a whitish juice, or milky fluid, into which the food is converted by digestion. It is a mix. ture of the oil and watery parts of the food, incorporated with the saline ones. Some of the ancients supposed the chyle was changed into blood in the liver, others

of them in the heart, but the moderns with more reason take the change to be effected by the lacteals, which absorb the chyle, and prepare it for combining with the blood, while the feculence of the chyme or ingested matter with the bile, are propelled into the large intestines.

Chylification commences by chewing the aliments or food in the mouth, and mixing it with saliva; when reduced into a kind of pulp, and received into the stomach, it is subjected to the action of the gastric juice, by which it is reduced to chyme; in the latter state it is mixed with bile; and from this mixture the lacteals of the mesentery and thoracic duct absorb a fluid which is perfect chyle.

The BLOOD is a red fluid, circulating by means of arteries and veins through every part of the body, serving for the support of life, and nourishment of all its parts. The blood when let out of the body gra dually separates into two parts, the one red which coagulates into a mass, and is called the cruor; the other thin and transparent, which retains its fluidity, and is called the serum. This separation is similar to the separation of curdled milk, into curds and whey. The proportion between the cruor and the serum varies much, the most common proportion is about one part of cruor to three parts of serum. The origin of the blood is in the chyle, which passing the lacteals, and mixing with the blood, they proceed together to the right ventricle of the heart, whence they circulate through the whole body. As to the heat of the blood, authors were formerly much embarrassed to account for it, but since the decisive experiments of Dr. A. Crawford, it is no longer doubtful that it originates in the absorption of oxygen from the atmosphere by means of a slow combustion in the lungs. To the same source may be attributed the redness of the blood, as venal blood is redder than the arterial. Red is, however, a' colour not absolutely necessary and essential, there being animals whose blood is white and limpid. The quantity of blood usually found in adults varies from 25 to 28 pounds of which 4 parts are contained in the veins and a fifth in the arteries. Its temperature is from 94

to 100 and in some females it amounts to 1049 of Fahrenheit.

The circulation of the blood, consists in a natural motion of the blood in every living animal; whereby that fluid is alternately conveyed from the heart to every part of the body by the arteries, and returned, by the veins, from the same parts to the heart. The circulation of the blood was discovered in 1628 by Dr. Harvey, a native of Folkstone.

Blood is now universally allowed to be the sole matter of nutrition to the animal body, and some physiologists even suppose that its red globules possess vitality. The blood of quadrupeds consists of nine different parts; its peculiar aroma or odorous part, fibrin or fibrous matter, (the chief source of the muscular fibre) gelatin or jelly, albumen or matter like the white of an egg, the red particles, iron, sulphur, alkalies, and water.

MILK is thicker, whiter, and sweeter than the chyle itself from which it is derived, and that probably with out much more alteration than the leaving behind some of its aqueous parts. Milk consists of butyrous, caseous, and serous matter. The butyrous parts are the cream and oil that swim on the top.; the caseous are the grosser parts, and those that coagulate, which are made into cheese; the serous are properly a lymph, and make whey. Milk is susceptible of both the vinous and acetous fermentations. Women's milk contains oil, curd, gelatin, sugar of milk, muriats of soda and potash, phosphat of line and sulphur.

OF THE SOUL AND ITS FACULTIES.

The SOUL is the immortal part of man, it is defined a spirit proper to inform and animate an organized body; and by its union to constitute a reasonable ani mal. Philosophers have not agreed in what part of the body the soul resides. Some suppose it equally dif. fused through every part others that it influences every part of the body, though it has its principal residence in some particular part. Des Cartes maintains its residence is in the pineal gland of the brain, where

all the nerves terminate: but all such opinions are mere conjectures.

MIND denotes that which thinks, feels, and wills in a thinking or understanding being. Philosophers allow of three kinds of mind, God, angel, and the human soul. The human mind is properly defined a thinking, rational substance. By thinking it is distinguished from body, and by reasoning from God and angels, who are supposed to see and know things intuitively, without the help of deduction and discourse. Mind or intellect signifies the intelligent power, intellectual capacity, and embraces all the human faculties which are independent of matter.*

PERCEPTION is that faculty by which the mind is informed of existences, the recipient of impressions, and is the act of perceiving, or apprehending; or that simple idea which we have of a thing, without making any affirmation or negation. Thus, when we hear the word ship, the power or faculty of forming an idea of it in the mind is called imagination: but when we hear of a thing whereof no image can be framed, the idea we then have is a mere perception. The power of perception constitutes what we call the understanding. The ideas we receive by perception are often altered by the judgment, without our taking notice of it; thus a man who reads or hears with attention, takes little notice of the characters or sounds, but of the ideas excited in him by them. The faculty of perception seems to be that which puts the distinction between

* 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, investigation, 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.

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the animate and inanimate part of creation. It is an intellectual principle, and found in some degree in all animals, and in them alone. Perception has been considered in three modes, the perception of ideas in our minds; perception of the signification of signs; and the perception of the agreement and disagreement of distinct ideas: but these may be reduced to two, sensation, and reflection. Sensation is the perception of an object by the organs of sense, as sight, hearing, &c. Reflection is the result of the mind, perception of its own faculties and operations.

Perception is also the first step towards knowledge, and the inlet of all the materials of it; so that the fewer perceptions a man has, and the duller the impressions that are made by them are, the more remote he is from that knowledge which is to be found in other men; he has less genius.

UNDERSTANDING is used as a general term to direct all the faculties of the human mind. Understanding refers to truths of every description which are not the immediate objects of sense; to facts, statements, relations, differences, &c. proposed to the mind; as we cannot say we understand what is really an object of sense, or what we see, smell or taste. Understanding signifies such a clear and decisive knowledge of a subject, or of some part of it, as to supersede the necessity of farther inquiry; it penetrates into the nature of facts and existences, ascertains the evidences on which they are founded, has a perfect insight into plans and projects, degrees of probability or improbability, consequences, &c. Understanding precedes intelligence and knowledge, as we say, a man of tolerable understanding, of great intelligence, of consummate knowledge.

JUDGMENT is the final act of the human mind, whereby it compares the ideas adduced by perception and reasoning, and decides on them accordingly. Thus the understanding compares the two ideas of the sun and the moon, and finding the idea of the sun greater than that of the moon, the judgment decides, and the will acquiesces in that decision.

The difference between perception, reasoning, and judgment is this; reasoning is that process by which we

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