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powers of producing others, and so of multi 2. Perspirable matter, excreted by the plying the species without end. These are vessels of the skin; powers which mock all human invention or 3. Sebaceous matter, by the glands of the imitation, they are characteristics of the Di- skin ; vine Architect.
4. Urine, by the kidneys; As the body is a compound of solids and 5. Ceruminous matter, secreted by the fluids, anatomy is divided into,
glands of the external ear; 1. The anatomy of the solids, and
6. Tears, by the lachrymal glands; 2. The anatomy of the fluids.
7. Saliva, by the salivary glands ; The solids of the human body consist of, 8. Mucus, by glands in various parts of
1. Bones, which give support to the other the body, and by various membranes. parts of the body;
9. Serous fluid, by membranes lining cir2. Cartilages, or gristles, which are much cumscribed cavities; softer than the bones, and also flexible and 10. Pancreatic juice, by the pancreas; elastic;
11. Bile, by the liver ; 3. Ligaments, which are more flexible 12. Gastric juice, by the stomach; still, and connect the ends of the bones to 13. Oil, by the vessels of the adipose each other;
membrane; 4. Membranes, or planes of minutely in 14. Synovia, by the internal surfaces of the terwoven and condensed cellular substance; joints, for the purpose of lubricating them;
5. Cellular substance, which is formed of 15. Seminal fluid, by the testes; fibres and plates of animal matter more 16. Milk, by the mammary glands. loosely connected, and which forms the ge The account of these animal fluids will be neral uniting medium of all the structures of found chiefly under the article PHYSIOLOGY. the body;
The anatomical description of the body 6. Fat, or adipous substance, an animal is technically arranged under the following oil contained in the cells of the cellular mem- heads: brane;
1. Osteology, or the description of the 7. Muscles, which are bundles of fibres, structure, shape, and uses of the bones. endned with a power of contraction; in po %. Syndesmology, or a description of the pular language they form the flesh of an connection of bones by ligaments, and of the animal;
structure of the joints. 8. Tendons, hard inelastic cords, which 3. Myology, or doctrine of the moving connect the muscles or moving powers to powers or muscles. the bones or instruments of motion.
4. Angeiology, or description of the ves. 9. Viscera, which are various parts, adaptsels engaged in nourishing the body, in abed for different purposes in the animal eco- sorption, and in the removal of superfluous pomy, and contained in the cavities of the parts. body, as the head, chest, abdomen, and 5. Adenology, or account of the glands in pelvis;
which various liquors are separated or pre10. Glands, organs which secrete or se pared from the blood. parate various fluids from the blood;
6. Splanchnology, or a description of the 11. Vessels, which are membranous ca. different bowels which serve various and nals, dividing into branches, and transmitting dissimilar purposes in the animal economy. blood and other fluids;
7. Neurology, under which title the brain, 12. Cerebral substance, or that which the nerves, and the organs of sense inust be composes the brain and spinal marrow, comprehended. which is a peculiar soft kind of animal The functions carried on in animals, in matter;
the explanation of which physiology consists, 13. Nerves, which are bundles of white and for the detailed account of which we fibrous cords, connected by one end to the refer the reader to the article PhysioLOGY, brain, or spinal marrow, and thence ex may be thus arranged. panded over every part of the body, in order 1. Digestion, or the conversion of extrato receive impressions from external ob neous matter into a substance fit for the jects, or to convey the commands of the nourishment of their own bodies. will, and thereby produce muscular motion. 2. Absorption, by which the nutritive
The Auids of the human body are, fluid is taken up and conveyed into the
1. Blood, which circulates through the vascular system, and by which the old parts vessels, and nourishes the whole fabric; of our body are removed.
OF THE HUMAN BODY.
3. Respiration, or the exposure of the kind of capsule, and in a looser form joinnutritive fuid to the action of the atmos- ing them to the neighbouring muscles, &e; phere.
When condensed into a firm and compact 4. Circulation, or the distribution of the structure, it constitutes the various memconverted matter to every part of the ani- branes of the body, which, by long macemal, for its repair and augmentation. The ration in water, may be resolved into a process is named circulation, from the mode loose cellular texture. Its general condenin which it is carried on in the generality of sation on the surface of the body constitutes . animals.
the cutis, or true skin, which is, in fact, a 5. Secretion, or the separation, and de- membrane. In the bones it forms the basis position of the particles composing the or ground-work of their fabric, a receptacle, structure of animals and vegetables, as well in the interstices of which the earth of bone as the formation of various substances which is deposited. As cellular substance is enthey produce from the circulating fluids.
tirely soluble in boiling water, it is ascribed 6. Irritability, or the principle by which by chemists to that peculiar modification of living fibres contract, by means of which animal matter termed gelatire. In conseabsorption and circulation are carried on, quence of its solution by the united agencies and which is more strikingly manifested by of heat and moisture, the muscular fibres the occasional exertions of the muscular separate from each other, and form the powers.
other structures of the body. This effect is 7. Sensation, by which animals become seen in meat which is subjected to long boilconscious of their own existence, and of that ing or stewing for the table, or indeed in a of external bodies.
joint which is merely overboiled. 8. Generation, by which new beings, si Its watery solution assumes, when cold, milar to the parents, are formed and pro- the appearance of jelly ; and, after a parduced.
ticular mode of preparation, constitutes
glue. PARTICULAR ANATOMICAL DESCRIPTION
The interstices of the cellular substance
are lubricated and moistened by a serous or After a cursory notice of the cellular sub. watery fluid, poured out by the exhalant stance, which forms the grand uniting me. arteries, and again taken in by the lympbadium of the various structures in the body, tics. It thus acquires a pliancy and softard of membranes, which are formed of ness, which adapt it particularly to serve as that substance, we shall proceed to describe a connecting medium for parts, which have the other parts, chiefly according to the motion on each other. The importance of technical arrangement above mentioned. this property will be best understood by ob
Cellular substance, or cellular membrane, serving the effects of its loss. Inflammation tela cellulosa or mucosa of Latin writers, is or abscess often causes an induration or conthe medium which connects and supports solidation of the cellular texture, bý which all the various parts and structures of the the integuments are fixed to the muscles, body. Any person may gain a general no the muscles are firmly united to each other, tion of this substance, by observing it in and to the surrounding parts, and the moa joints of veal, where it is always inflated tions of the whole are considerably im. by the butchers. It consists of an assem- paired. blage of fibres and laminæ of animal matter, From the universal extent of this cellu. connected to each other so as to form innu- lar texture, two conclusions may be drawn; merable cells or small cavities, from which ist, it forms the basis of the whole animal its name of cellulur is derived. It pervades fabric, in such a way, that if we conceive every part of the animal structure. By every part removed but this, the form joining together the minute fibrils of muscle, of the whole would still be expressed in celtendon, or nerve, it forms obvious and vi. lular substance; 2ndly, it forms a connecsible fibres; it collects these fibres into tion and passage between all parts of the large-fasciculi; and by joining such fasci- body, however remote in situation, or disculi or bundles to each other, constitutes similar in structure. For the cells of this an entire muscle, tendon, or nerve. It substance every where communicate ; as joins together the individual muscles, and is we may collect from facts of the most comcollected in their intervals. It surrounds mon and familiar occurrence. In emphyeach vessel and nerve in the body; often sema, where air escapes from the lung connecting these parts together by a firm wounded by a broken rib, into the cellulat
substance, it spreads rapidly from the chest liar habit or disposition of the individual. into the most remote parts of the body; It is not found in the early periods of fatal and has even been known to gain admission existence ; and cannot be distinguished with into the eye-ball. A similar diffusion of this any certainty sooner than the fifth month Auid may be effected by artificial inflation, after conception. which is commonly practised by butchers In the fætus, and for some time after on the carcases of calves. In anasarca, or birth, the fat is contined to the surface of preternatural accumulation of fuid in the the body, and is only found in a stratum cellular substance, the most depending parts under the skin. It begins, however, graduare the most loaded; and punctures in these ally to be deposited in the intervals of the drain the water off from the whole body. muscles, and on the surface of some viscera.
Adipous substance, or fat.-The cells of In old subjects, however thin they may the cellular substance, in many parts of the seem on an external view, there is always body, are destined for the reception of a much fat, penetrating even the substance fluid, termed fat. This is of an unctuous of the muscles : the bones are greasy nature, inflammable, lighter than water, throughout; the heart is more or less loaded, usually inodorous, and, generally speaking, as are also the parts in the abdomen. similar to the vegetable oils. It is white in There is a considerable difference in the young animals, and becomes yellower as quantity of fat in different individuals; and they advance in age : this difference may be in some there is a propensity or disposition seen in the carcases of a calf and cow. It to its accumulation ; a sedentary life, cois always more or less fluid in the living sub- pious food, and tranquil state of the mind, ject; in carnivorous animals, and in man, are particularly favourable to the increase it retains much of its oily appearance after of fat, which sometimes proceeds to such death ; but in herbivorous animals it con a pitch, from the continuance of these stantly assumes a concrete form. Dr. Hun- causes, that it must be considered as a dister called those parts of the cellular sub ease, and is attended with the greatest instance, which contain fat, adipous cellular convenience to the individual. General dissubstance; and distinguished the other by eases of the frame are commonly attended the epithet reticular.
with an absorption of the fat from the celAs the fat is deposited in cells, it assumes lular substance : acute disorders cause a in general a kind of granular form. It va very rapid emaciation. In no case is the ries considerably in consistence. That of adipous substance more completely removed the orbit is the softest in the body, and from the whole body than in anasarca, forms a well-known epicurean bonne bouche, where its place is supplied by a serous in a boiled calf's head. The fat about the fluid. kidneys becomes particularly hard after The uses of the fat seem to be, in part, death, and is called suet. The globules or common to it with the cellular substance : portions of this are very large, and it con it connects contiguous parts, and at the tains on the whole less cellular substance same time prevents their coalition. It ad. than any fat in the 'body. There is gene mits of their moving on each other withi rally a layer of fat under the skin ; whence freedom and facility. Its deposition under a membrana adiposa has been sometimes the integuments gives a roundness and conenumerated as one of the common integu: vexity to the surface, on which the beauty ments of the body.
of the human form principally depends. Some parts of the body never contain Indeed, its accumulation in particular situfat, even in subjects who have the greatestations immediately influences the outline of accumulation of this fluid. This is the case the part; as in the orbit, the cheek, and the with the scrotum, the integuments of the buttocks. The effects of its loss is most penis, and the eyelids : it is obvious that the disagreeably manifested in the lank cheek functions of these parts would be com and hollow eye of an emaciated patient. pletely destroyed, if they were subject to It has been supposed that the fat absorbed the enormous accumulations of fat, which under certain circumstances is applied to occur in other parts of the body. Several the nutrition of the body; as in hybernatof the viscera also never contain any fat; ing animals. probably for the same reason, this is the Membranet. In the foregoing observacase with the brain and lungs.
tions on cellular substance, we have stated The quantity of fat varies according to that membranes are formed by a condensathe age, the state of bealth, and the pecu• tion of that substance. They consist of
thin sheets of compacted and close cellular holding any other liquors, it is essentially texture. This is proved by long maceration necessary that membranes should be imperin water. The fluid gradually penetrates the meable to fluids in the living state. interstices, and resolves the membrane into a loose and floculent substance. They are found in every variety of density and softness. The bones are the most solid parts of the
A grand use of membranes is to line what body. They are composed of a vascular anatomists call the circumscribed carities of substance, not differing materially in structhe body. These are hollow spaces, con ture from that of the rest of the body, ex. taining the different viscera, and in every cept that there is deposited in its interstices instance completely and accurately filled by an earthy matter, which gives to the whole such viscera; so that the term cavity, when mass rigidity, strength, and a permanent filised by anatomists, does not, as in common gure. The nutrient vessels of arteries, mem. language, denote a void or empty space. branes, and ligaments, occasionally deposit
Membranes have a smooth internal po- lime, and cause the ossification of those lished surface, turned towards the contained
parts. viscera. This is constantly moistened by a The account of the original formation of lubricating fluid exhaled by the minute ar the bones in the fretus, is technically termed teries of the part, and bestows on the sur
osteogeny. The parts of the young fætus, face of the membrane the greatest softuess which are afterwards to become bones, are and smoothness. Hence the motions of the
at first cartilaginous; and their substance is viscera are performed with perfect facility, rendered white and firm in proportion to and they are prevented from adhering to the quantity of lime deposited in it. The each other, or to the sides of the containing quantity at the time of birth is only suthcavity. The extent of such cavities is cient to give firmness to the whole mass, bounded and defined by the lining mem not to prevent its flexibility, branes, and hence arises the epithet circum The extremities of all the long bones conscribed. To increase the facility of motion, sist of large portions of cartilage, and these, the surface of the contained viscera is co by degrees become bony. The formation vered by productions of the same mem of bone begins in the centre of the cartilage, brane, and always therefore possesses the and gradually extends from thence to the same smoothness and polish with the sides
remote part so that the separate piece of of the cavity. In the carcase of an ani- bone, formed at the extremity, remains till mal just slaughtered, the lubricating secre near the time of puberty, conjoined to the tion flies off in the form of a fine vapour, body of the bone by a crust of cartilage. In when the cavity of the belly or chest is laid this state it is technically termed an epiphyopen. It is nothing more than an increase sis. The body, or middle part of the bone, of this natural secretion, combined perhaps is called the diaphysis. The projecting with a deficient absorption, that gives rise parts, or processes of bones, are also in to dropsies of the different cavities.
many instances originally epiphyses. The The opposite or external surface of the time by which these epiphyses are consolimembrane is rough and cellular ; and ad- dated by a bony union with the diaphysis, heres to the various parts, which form the varies in different bones, but it is not prosides of the cavity.
longed in any much beyond the age of puAnother use of membranes is to form berty. blood-vessels, or tubes, for conveying the We perceive an evident advantage in the nutritious fluid to all parts of the body. The bones of the fætus being formed as they are. bore or hollow of the tube is perfectly smooth Their flexibility admits of the form of the and polished, so that the blood experiences limbs becoming adapted to the varying fiDo obstruction in its course ; and the exter gure of the pelvis, through which they must nal surface is rough, to connect it with the pass; and their elasticity, which is powersurrounding parts. In a similar manner are ful, restores them afterwards to their natural formed the stomach and intestines, which shape. receive the food ; the urinary bladder, The aninial substance contained in bones which holds the urine, &c.
is demonstrated by immersion in weak acids, It must be obvious, that for all the pur- which dissolve the earth, and leave a kind poses which we lave enumerated, whether of cartilage similar to that in which the bone for lining circumscribed cavities, for con was originally formed. Long boiling in a veying the blood, for receiving the food, or close vessel removes the gelatinous sub
stance, which is dissolved in the water. The at their extremities, to afford an extent of earth of bones is demonstrated by calcina- surface for the formation of joints, and the tion, which drives off the animal matter, and support of the weight of the body. A caleaves the earth alone behind. This earth vity is left in the middle ; for if all the consists chiefly of phosphate of lime; but earthy matter had been compacted into the there is also a small proportion of carbonate smallest possible space, the bones would of lime. In young subjects the animal sub- have been such slender stems, as to be very stance predominates ; and the bone appears unsuitable to their offices; and if they had redder, in consequence of the arteries being been of their present dimensions, and solid larger and more numerous. The bones of thronghout, they would have been unneces. old persons contain more earth, and are con sarily strong and weighty. sequently wbiter and less vascular.
The phenomena, which result from feedSome recent experiments have shewn the ing an animal with madder, sufficiently dequantity of jelly contained in bones to be monstrate the existence of blood vessels much larger than was supposed, and as it and absorbents in the bones. There is a forms a very good soup when dissolved in strong attraction between the earth of bone water, the circumstance is of considerable and the colouring matter; by means of importance, as furnishing an article capable which they unite and form a beautiful red of supplying much wholesome nutriment. substance. The whole of the bones of an The quantity of soup furnished from a given animal assume this colour soon after an apibulk of bruised or pounded bones, boiled in mal has been taking the madder. If it be a vessel with a closed lid, considerably ex- left off, the bones in a short time , resume ceeds that which can be extracted from the their natural white appearance, from the absame quantity of meat. Of course the arti- sorption of the red colouring substance. cular heads of bones, and the reticular tex The short time in which growing bones beture, in general furnish the greatest quan come thoroughly died, and in which again tity.
the preternatural tint is lost, prove that It has been generally taught, that bones
even in these, the hardest parts of our are composed of fibres and laminæ : the frames, there is a process of removal of old fact is that they consist of a reticulated tex
parts, and deposition of new ones constantly ture, very similar to cellular substance in going on. other parts of the body.
That bones possess nerves, as well as arAccording to the obvious differences in teries, veins, and absorbents, cannot be their forms, bones are divided into the long doubted. Although in the natural state they and flat.
seem to be insensible, they become exTwo kinds of structure may be observed tremely painful when discased ; and again, in all bones : in the one, the bony substance a fungus which is sensible sometimes grows is condensed, and leaves no interstices; in out of a bone, though it may have no conthe other, there is a mere net-work of bony nexion whatever with the surrounding soft fibres and plates, leaving numerous inter- parts ; of course it must have derived its vals. The latter is termed the cancellous nerves, by means of which it possesses sensubstance of bones.
sation, from the bone out of which it arose. The cylinder of a long bone is composed
Bones are covered by a strong and firm entirely of the firmer substance, and in its membrane, termed periosteum, on which the centre is hollowed out to contain the mar vessels are first distributed; from this they row. In those extremities of the bones, descend into the substance of the bone. which form the joints, which are greatly ex
The vessels enter through holes, which are panded, in order to increase the extent of evident on the surface, and which are larger surface, there is a thin layer of the compact and more numerous in the extremities of substance, but all the interior is cancellous. the long bones than in the middle. In broad or flat bones, the firmer substance is formed into two plates or tables, and the
OF THE MARROW, interval between these is occupied by can This is of an oily nature. It hardens, celli.
when cold, in herbaceous animals; but it Many advantages arise from this arrange- remains fluid in those which are carnivoment of the earth of bones. The long bones rous. It has a reddish and bloody appearare made slender in the middle, to allow of ance in young animals ; but this soon goes the convenient collocation of the large mus- off. It is contained in fine membranous cles around them; they become expanded cells, which do not communicate with each VOL. I.