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THE

No. XV.

PUBLISHED BY WILLIAM SMITH, 113, FLEET STREET.

SATURDAY, APRIL 13, 1839.

THE HABITATIONS OF THE POOR. MANY years ago, we were a juvenile auditor amongst a crowded assembly in the chapel of a provincial town, listening, with eager attention, to the statements of a well-known African traveller. All that he then uttered has faded from our recollection, with the exception of a single incident in the discourse. Speaking of the degradation of Africa, and its deficiency in even the very elements of civilization, the reverend traveller lifted the open Bible from the pulpit cushion, and told his audience that the streets of Latakoo were no wider than that. If the manner as well as the matter of this fact struck the audience as it did the writer, the impression made must be numbered amongst those which are called indelible. Let us suppose an intelligent native of Latakoo or Timbuctoo halting at the foot of that great thoroughfare, Holborn Hill, and venturing to peep up narrow, crocked, notorious FIELD LANE. "Here," he might exclaim, "in the greatest, the noblest, the mightiest capital of the world, is a street which reminds me of my ative town! It is crooked, turns round with a fine curve; narrow, so that two persons can hardly pass without jostling each other; busy, like the busy thoroughfare of a great metropolis!" Yes! stranger, fear not to enter Field Lane! Once on a time, you might have been dragged into a Jew's den, hustled, or teased: but there is no danger now; the invisible strong arm of the law follows you along Field Lane. Here, as you perceive, is a type or a memorial of those streets of London of the olden time, along which Great Plagues walked, or over which Great Fires triumphed. Standing in the centre of this famous alley, you can almost touch the houses on either side-those old dingy, dirty, tumble-down wooden houses, toppling towards each other. Their basements are occupied by old clothesmen, or rather old ragmen, dealers in rusty locks and nails, and polishers of old boots and shoes. But stay there seems to be some kind of obstruction a little way up the alley. Banners of many-coloured hues and patterns are floating over-head, and shut up the vista-are these the banners of some knight-errant order, and is this the chapel royal where its installations are held? Venture further, and fear not; these banners are those convenient affairs without which a man scarcely feels himself a man, and the corner of one of which, projecting from the coat pocket, was formerly the sign of a fop or a fool. The vendors will sell you one, cheap, if you can deal with them-but ask them no questions respecting the merchants who supply them with their stock!

Suddenly Field Lane terminates in a street somewhat wider than the paved alley through which we have come. This street boasts a little slip of pavement on either side, and a morsel of causeway in the centre. Its width lets in more of heaven's light and air than can fall down on Field Lane-but this only serves to reveal more fully the dingy, squalid, filthy aspect of the place. It rises up an eminence, and is known as Saffron Hill-strange, that like Rosemary Lane, some of the filthiest spots of London should have name and nature standing as antipodes! Inhabitants, not native, nor yet "to the manner born,” may be seen standing at some

VOL. I.

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of the entrances, and heavy feet may be heard making the wooden stairs to creak; here reside the Paddy Kews, and the Bill Sikeses, the Dennis O'Raffertys, and the Artful Dodgers, who assist in maintaining our vast judicial establishment-our judges, and our barristers, and our attorneys, in active employment. Is it summer evening, and are you pensively inclined? Come here, and have your ideas of the nature which you wear cast down to the ground and fit to be trampled under foot-for out of some passage a number of men, women and children, may rush, some covered with blood, others fighting like furies, while the howlings, yells, and cries, make the place seem an abode of demons. Or is it a Monday or a Tuesday morning, and have you ascended a little higher? Groups of men and women, evidently of the lowest rank in society, are standing along the edge of the narrow pavement. Is there some procession about to pass ? It is only the customary collection, awaiting to see the prisoners proceeding by the back way to Hatton-Garden Police-Office. But what is this curious machine that rumbles through the narrow street? It seems a compound of the hearse and the omnibus-too slightly constructed as a conveyance for prize oxen, or as one of the waggons of a menagerie -yet built for animals of some kind; for though no windows are in the sides, light and air are admitted through a grating on the top. Mark the driver-he is in uniform, and drives soberly; the conductor behind is also in uniform; his hand is on the handle of the carefully-shut door, and he does not look around for passengers. Nothing appears on the vehicle to indicate its nature, save the royal arms and "V. R."-the mystery is revealed, it carries a cargo to the House of Correction!

What connexion is there between dirt and crime? between a tumble-down house and moral degradation? Does Spitalfields supply the Central Criminal Court with as many subjects as Saffron Hill or St. Giles? Is the mind as well as the body under the influence of a puddle and tainted air? Does cleanliness rank next to godliness? Scotland has long held a conjoined character, and has been famous for orderly habits and dirty ones; and in Ireland, where too many live in mud hovels, and huddle together, the standard of female personal character is comparatively high. But in London, the chief abodes of vice as well as misery, of crime as well as poverty, have ever been its dirty, dingy, squalid spots. The mazes of the Seven Dials and of St. Giles, lying like a breakwater between the "east" and the "west" ends; squalid Tothill Street and its neighbours, within a stone-throw of venerable Westminster Abbey and the Houses of Parliament; Saffron Hill, or Spitalfields, or Ratcliffe Highway, or Rosemary Lane, names which are each the representatives of a congeries of low and miserable lanes, alleys, and streets, are all notorious for whatever sinks man into something worse than a beast. They are Sloughs of Despond," that mending seems only to mar; where inexperience, and modesty, and ingenuousness, are too apt to disappear, and then to rise again to the surface, changed into rioting, drunkenness, recklessness, shameless effrontery, and dextrous cunning.

"The labouring classes," says the prospectus of the Society for bettering the Habitations of the Industrious Poor, "are, in most

Bradbury and Evans, Printers, Whitefriars,

cases, densely congregated (one house being usually inhabited by several families) in the alleys, courts, and lanes of the metropolis. Their dwellings, owing in some cases to the poverty, in others to the vicious habits, of their occupants, are, for the most part, devoid of cleanliness, order, or comfort. Some families, indeed, enjoy the comparative luxury of a separate day and sleeping-room; but the great majority possess only a single apartment, which is at once the day-room and the common sleeping-place of parents and children. Others, in a more destitute condition, are still more densely congregated, several families occupying the same room; an arrangement necessarily productive, not only of bodily disease, but of a still more baneful moral contagion, the diseased and the healthy being crowded together, and the young and innocent brought into immediate association with the hardened and abandoned.

"But a closer and more circumstantial knowledge of the existing condition and manner of living of the working classes, may be obtained from the following results of a laborious investigation, lately instituted in one of the districts of the parish of Marylebone, namely, that, in 315 houses which were visited, the number of families was 915; the number of families in which there were children, 578; the number of children, 1575. The habitations generally had a bare, desolate, and untidy appearance; nothing had an appropriate place. There were 510 children who went to school, and 1065 who did not. Of the girls who had learnt to sew and wash, there were 492, and 227 who had not; the number of children bringing up to some trade was 160, and no less than 1415 who were not; 349 families appeared cleanly and healthy; 175 dirty, but healthy; 53 dirty, and unhealthy; 58 much distressed; 513 had a good supply of water, and 64 had not. Drains, sewers, and pavings, were wholly wanting in some of the courts and alleys.

"In one district, called the Hell, there was a large unoccupied piece of land before the houses, full of mud, manure, and stagnant water; 324 families were here living in airy rooms, and 249 in confined rooms; there appeared to be a general ignorance on the subject of ventilation: although the air in many of the rooms was impure in the highest degree, so as to be extremely disagreeable to those entering them, the parents seemed to be seldom alive to the propriety of opening a window. But there is one fact, of a character which cannot but be peculiarly afflicting to those who hear it; out of 578 families with children, 308 were found to be occupying only one room, and consequently father, mother, brothers, and sisters, were all sleeping together!" It is added, that other facts could be related of an equally demoralizing tendency, even with regard to children of the tenderest years, but that they are of a character unfit for publication.

Such is one feature of this "great metropolis;" a city not only great in its extent, but great in its charities-a city crowded with churches, and chapels, and hospitals, a great central dépôt of the world's benevolence, enterprise, and humanity! Other large cities of this most Christian kingdom present, according to their respective sizes, and the variable nature of their population, similar incongruities. Birmingham and Manchester, Leeds and Liverpool, Edinburgh and Glasgow, contain deplorable contrasts; but Dublin, as might be expected, exhibits them in shocking opposition. Under the walls of the "Castle" lie streets more squalid, more filthy, and more deplorable, than even those of the filthiest part of St. Giles; while the stranger cannot walk in any quarter without being incessantly reminded of the abject and helpless poverty of a very large body of the inhabitants. There, too, may be seen human beings-creatures bearing the shape and

houses, but crouching in some excavation, made perhaps in a heap of rubbish.

These, it may be said, are anomalies in our civilisation, blots on our social condition; but they are inevitable in our present state of society, and their removal must only be waited for in its gradual progress and amelioration. Look, it may be added, at all that has been already done; compare the condition of the labourer of the present generation with that of his predecessor; and see the great changes that have been effected in the outward condition and aspect of our large towns. We are quite aware of all this; and, to our minds, it is an additional inducement for active and extraordinary exertions to remove the evils that still exist. English society has within it materials for a tremendous explosion. We are fast advancing to a state of active revolution. Far would we be from enacting the worse than useless part of a mere alarmist-of shouting "Wolf! wolf!" or proclaiming falsely that there is a lion in the street. But the rapid growth of our population-the disjunction and determined opposition of great masses-the extraordinary ignorance that yet prevails amongst large sections of the population - -are all calculated to make thoughtful minds look forward with anxiety. Hitherto the vital energy of that great and influential portion of British society, the MIDDLE CLASSES, has carried us safely through the changes and alterations that have taken place. As long as that heart of England remains sound, we need fear no evil. But the middle classes are exposed to the action of circumstances calculated to impair their strength and vigour. We have no right to expect that they will continue to present an effectual resisting medium to the accumulating pressure from below; and our only effectual remedy is at once boldly to descend, and examine the nature and extent of that evil, which may otherwise roll its dark and turbu lent waters over the whole structure of our civilisation.

A society has been formed, which proposes to take effectual measures for "bettering the habitations of the industrious poor" in the metropolis. The idea is admirable. The condition of the habitations of a people is a grand test of their state of civilisation. Were the nests and rookeries of large towns pulled down, and their places supplied by comfortable habitations, adapted to the resources of the working classes, a vast improvement would be made on their whole moral, mental, and physical character. But how is this to be accomplished? Certainly, not by the classes themselves. Setting aside the helplessness of their position, they have received but a very small share of that knowledge so widely diffused amongst the middle classes, and which has taught them the means of remedying evils formerly tolerated as part and parcel of their existence. As little are we to expect that the improvement will proceed from the landlords of St. Giles or Saffron-hill. "With respect to the rents paid for their miserable accommodation, it may be observed, that the lodging-houses of the labouring classes are now generally in the hands of persons who lease the whole and sub-let the rooms at weekly rates, vary ing from 1s. 6d. to 4s., and even as high as 5s., each; a price which is calculated to be double the sum paid for similar accom modation by the higher classes, who enjoy the additional advan tages of a more convenient house in a superior situation. It has been ascertained, for instance, that a house in the parish of Marylebone, costing in annual rent and taxes 437., produces, when let off in rooms at weekly rents, the sum of 617. 19.; yielding to the first lessee a profit of 211. 10s. A smaller house, costing the lessee 127. per annum, .ent and taxes, readily produces 201. per annum, when let off, as before stated. instance, therefore, the profit is one-half; and, in the second,

name of man-living, not in damp cellars, nor yet in ruined two-thirds of the original rent.

In the first

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These high charges, of which, be it observed, the vicious are the principal cause, and the well-conducted the victims, are necessarily made, not only in consequence of the frequency with which the weekly rents are wholly evaded by the lodger, but to cover the expense of repairing or replacing fixtures damaged or destroyed by tenants of careless or profligate character. Indeed, so great is the loss sustained on property of this nature, that the owner of a number of four-roomed houses in Marylebone parish, let in lodgings, under the present system, wearied out by the uncertainties of payment, and by the continual outlay caused by wanton destruction, lately offered the whole on a repairing-lease for the mere ground-rents, thus at once consenting to sink the entire cost of the erection and fittings of the dwellings."

We know nothing whatever of the infant society, whose prospectus has led us into writing the remarks we have made. Much perseverance, much caution, and much skill, will be requisite in the conducting of the experiment. We are not very sanguine about its success. But if it goes straightforward in its plan; if it carefully eschews any attempt to convert the society into a political engine, and avoids all attempts to patronise or manage its tenants, or to undermine the natural independence of character which should be cherished, then we cordially wish it success.

"It is intended that the society shall take, on lease, some courts, alleys, or small streets, conveniently situated, and as far isolated as possible from the influence of evil association. The houses in the first instance are to be thoroughly repaired and drained; and provided with every requisite for due ventilation and warmth, together with such accommodation, as to cupboards, shelves, &c., as may contribute, at small expense, to the reasonable comfort of the tenants.

"The houses thus prepared are intended to be opened for the reception of weekly lodgers, on such a scale of rents as may be compatible with the expenses and liabilities of the society. And as it may be presumed that a respectable society, becoming the responsible tenant, and sub-letting the dwellings to persons of good character only, could obtain them at a rate somewhat lower than the present rent, it follows that the tenants of the society may reap a corresponding advantage.

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The immediate object of this society, then, is to provide for the deserving poor, at a rate somewhat below the current rents, apartments of an improved description, arranged and conducted with a careful reference to the health, comfort, and morals of their occupants. In effecting this desirable object, the society's operations cannot fail to act as a premium on good conduct in the working classes generally, even beyond the circle of those more immediately benefited. They will teach a great moral lesson, in a form palpable to the senses of those whom they cannot directly influence, by connecting solid advantages with good conduct, and thus stamp such a value upon character, as will encourage the well-disposed to persevere in a respectable course, and prove an inducement to the idle and vicious to forsake habits of life pregnant with degradation and suffering.

"It is hoped that an institution of this kind will be considered peculiarly adapted to the present day, since the prominent aim of recent legislation for the poor has been to eradicate the demoralising system of voluntary pauperism, and to mature a healthy feeling of self-respect, and an honourable determination to look to the fruits of industry alone for subsistence."

We are reluctant to make promises: but there are necessarily a variety of subjects which, on their first introduction into a periodical such as ours, can only be briefly discussed, leaving details to future articles. The "Habitations of the Poor" is one of those subject

WE MIGHT HAVE BEEN!*

BY THE LATE L. E. L.

WE might have been!-these are but common words,
And yet they make the sum of life's bewailing;
They are the echo of those finer chords,
Whose music life deplores, when unavailing.
We might have been!

We might have been so happy, says the child,

Pent in the weary school-room during summer, When the green rushes, 'mid the marshes wild, And rosy fruits attend the radiant comer, We might have been!

It is the thought that darkens on our youth,
When first experience-sad experience teaches
What fallacies we have believed for truth,
And what few truths endeavour ever reaches.
We might have been!

Alas! how different from what we are,
Had we but known the bitter path before us;
But feeling, hopes, and fancies, left afar,
What in the wide bleak world can e'er restore us?
We might have been!

It is the motto of all human things,

The end of all that waits on mortal seeking; The weary weight upon Hope's flagging wings; It is the cry of the worn heart, while breaking➡ We might have been!

And when, warm with the Heaven that gave it birth,
Dawns on our world-worn way Love's hour Elysium,
The last fair angel lingering on our earth,
The shadow of that thought obscures the vision,
We might have been!

A cold fatality attends on love,—

Too soon, or else too late, the heart-beat quickens ; The star which is our fate springs up above, And we but say-while round the vapour thickensWe might have been!

Life knoweth no like misery,-the rest
Are single sorrows,-but in this are blended
All sweet emotions that disturb the breast:
The light that was our loveliest is ended.
We might have been!

Henceforth how much of the full heart must be
A sealed book, at whose contents we tremble?
A still voice mutters, 'mid our misery,
The worst to hear-because it must dissemble-
We might have been!

Life is made up of miserable hours;

And all of which we craved a brief possessing, For which we wasted wishes, hopes, and powers, Comes with some fatal drawback on the blessing. We might have been!

The future never renders to the past

The young beliefs intrusted to its keeping. Inscribe one sentence-life's first truth, and last,On the pale marble where our dust is sleepingWe might have been!

From the New Monthly Magazine.

THE STRUCTURE AND FUNCTIONS OF THE HUMAN FRAME.

ALL living bodies, whether vegetable or animal, are composed of organs (instruments), that is, of parts having a determinate structure and form, and performing specific functions or actions, thus giving rise to the phenomena which collectively are denominated life. For example, the heart is an organ, the function of which is the circulation of the blood. Anatomy is the science which relates to organs; Physiology, to functions; the one is the science of organisation, the other of life.

Organs are divided into two classes, differences in the functions they perform being the basis of the classification. Some functions have for their purpose the support and protection of the individual being and the perpetuation of its species: others are subservient to sensation and voluntary motion. Taken collectively, the functions of the former class are designated by the expression, "organic life;" those of the latter by the expression, "animal life." Organic life (which is sometimes, and, in our opinion, with less ambiguity, denominated, vegetative life) is possessed by all organised beings, vegetables as well as animals,-hence its name. Animal life is so called because it is characteristic of animals alone, vegetables being altogether destitute of sensation and the power of spontaneous motion.

This distinction between the two great divisions of the organic world occasions important formal differences between them even in those points in relation to which they essentially agree. It is evident, for example, that the nutritive organs of beings which move from place to place must vary considerably from those possessed by beings which remain fixed in the same spot and are constantly in contact with their food, as is the case with vegetables. All the parts of an organised being are closely connected with, and exert great influence upon one another, and therefore each must be formed in reference to all the rest, in order that they may cooperate harmoniously. In the animal, the organic functions are subordinate to those of the animal life, and are modified in accordance with them. Nevertheless, the former are carried on independently of the latter, and sometimes even after they have wholly ceased. The heart may continue to beat, although the brain, the organ of sensation, has become incapable of performing its office. The organic life, on the contrary, is essential to the animal: the instant the vegetative functions stop, animal life is destroyed. It rests upon the organic-the organic is independent and original. Gradual development is one of the characteristics of organised beings. Unlike mere matter, which, so far as our observation extends, has neither commencement nor end, their individual existence has a clearly marked beginning as well as termination. Small and feeble at first, it is only by degrees, in many instances by exceedingly slow degrees, that they attain their full size and vigour. The acorn is an organised body, the germ of the future oak. It contains the yet feeble living principle, and the rudiments of the organs which in process of time will attain the strength and magnificent development of the mighty tree, formed to endure for centuries, and successfully to resist the operation of the allpowerful elements. It is long before the weak and helpless infaut becomes the powerful man: the change from one state to the other is so gradual as to be almost unobserved. In both these instances the phenomena referred to consist in the increase of the size of the organs composing the body. To prepare the materials thus disposed of, and to arrange them in their proper order, is one of the functions of organic life.

No function can be performed without waste of the substance of the organ by which it is carried on: hence, but for compensatory processes, organised beings, instead of increasing or maintaining their bulk, would be in a state of incessant decay and diminution. The constituent particles of all living bodies are in a perpetual flux: every instant old particles are carried out of the system and new particles are brought into it. The functions by means of which the compensation above mentioned is effected, are the same in kind, though differing in degree, as those which develop the germ and bestow upon it the proportions of maturity. All forms of being existing on the surface of our globe are exposed to the action of physical agents, and are subject to the operation of physical laws. Air, water, light, heat, cold, electricity, are constantly at work, disorganising some bodies and reconstructing others. The hardest rock is not exempt from their destroying influence. The process may not be perceptible, yet it gradually moulders away beneath their united operation, and enters into new combinations. Yet the most fragile plant or the minutest animal modifies the action of these seemingly resistless elements.

So long as the living principle is vigorous, they, within a certain range, are rendered subservient to it,-nor, indeed, could life be otherwise maintained. This remarkable characteristic of organisa. tion is also the result of the functions of the organs of organic life. The materials out of which nutriment (that is, the matter which develops and maintains the body) is elaborated, are called food. The food of vegetables consists of inorganic matter, chiefly air and water. That of animals is derived from the organic world, either vegetable or animal, the food of man being of both kinds. To extract from the food those portions of it which are fit to become incorporated with the body, is the office of one set of the organs of organic life, to which the name digestive (separating) has been given.

The mouth and teeth perform the first part of the digestive process. In the mouth the food is divided into minute fragments by means of the teeth, the muscles of the lower jaw, and the tongue, and is mixed with various fluids, the chief of which is saliva. The food, having thus been reduced into a soft pulp, passes down the esophagus or gullet into the stomach, a membranous bag, capable in the adult of holding about three pints, and situated in the upper part of the abdomen. There it is exposed to the action of the gastric juice, a fluid secreted (that is, separated from the blood) by the minute blood-vessels of the internal lining of the stomach, or mucous coat. The gastric juice is universally considered by physiologists to be the principal agent in effecting the changes which the food undergoes in the stomach, consisting in the complete dissolution and intimate mixture of all its component particles; so that, however numerous and varied may have been the articles eaten, they are converted into a mass perfectly homogeneous, that is, possessing in all its parts the same sensible qualities, though, of course, partaking of the character of the food from which it is formed. This new product, the result of the second stage of the process of digestion, is called chyme.

As the chyme is gradually formed from the food in contact with the mucous coat, it is carried by the contractions of the muscular coats towards the right extremity of the stomach, where it accumulates until admitted through the pyloric orifice into the first intestine or duodenum, so named on account of its usual length, which is about twelve inches.

This chamber is a second stomach, which continues the process commenced in the first. It is assisted by two organs of considerable magnitude, the pancreas and liver, the former lying immediately behind the stomach, and resting upon the spinal column, the latter situated on the right side of the abdomen, above and in front of the pyloric extremity of the stomach. Both these organs belong to that class of the organs denominated glands, whose functions consist in the separation of peculiar fluids from the blood, which are used for various purposes in the animal economy, and of which saliva and tears are well-known examples. The secretion of the pancreas is called the pancreatic juice, that of the liver, the bile. These fluids are slowly, drop by drop, conveyed by small tubes or ducts into the duodenum, and perform an important part in the changes effected in the chyme.

The duodenum secretes a fluid which possesses a solvent power analogous to that of the gastric juice. By its admixture with this and the two above-mentioned secretions, all of which are highly animalized, the chyme is brought nearer the chemical constitution of the blood, and the separation of its nutritive from the excrementitious portions appears to be facilitated. Soon after it is mixed with the bile, the compound separates into a whitish tenacious fluid called chyle, which is the nutritive essence of the food, and into a yellowish grey pulp, its useless refuse. The chemical qualities of the chyle differ in an important respect from those of chyme; the latter is acid, the former alkaline. It is this change which assimilates it to the blood.

The motions of the duodenum are irregular-first in one direction, then in another; yet gradually they propel its contents into the second portion of the small intestines or jejunum, whence they pass into the last or ileum. The inner or mucous coat of these tubes, especially of the former, is disposed in folds, which serve the double purpose of affording a greater absorbing surface and of retarding the progress of the chyle, so that none may be lost. These folds are thickly studded with innumerable absorbent vessels, the mouths of which, so small as to be invisible to the unassisted eye, open on the surface of the intestines and take up the chyle. These vessels are exceedingly minute, and composed of membranous coats, so transparent that the colour of their contents is distinctly seen through them, from which circumstance they derive their name, lacteals or milky-vessels. The lacteals penetrate the coats of the intestines, and, gradually converging, at length unite and

form the thoracic duct, by which the elaborated chyle is conveyed
upwards through the thorax or chest, and poured into the left
subclavian vein. Thence it passes into the superior vena cava,
which conveys it to the right side of the heart.
Meantime, the innutritious portion of the food, mingled with
various animal substances, no longer fit to remain in the system,
enters the large intestines, along which it is slowly moved by the
action of their muscular coats; and every particle of nutriment
having been extracted from it by absorbing vessels, which exist, in
greater or less abundance, in all parts of the intestines, the residue
is expelled from the body.

We have thus traced the changes which food undergoes in the digestive organs, extracting its nutritive portions and assimilating them to the blood, and have followed the course of the chyle until it mingles with the vital current. Another change is yet necessary, however, to render that fluid capable of supporting life. Before we explain this final process of digestion, it will be convenient to give an account of the blood and its circulation; the process which completes the elaboration of fresh nutriment also exercises a most important influence upon the perfectly formed blood.

Blood is the fluid by which life is supported: its elaboration from food, and its maintenance in a pure and healthy state, is the object of the combined operation of nearly all the organs of organic life. In proportion as these grand processes are performed well or ill, the entire animal economy enjoys good or suffers ill health. Though apparently a simple fluid, blood is in reality one of the most complex substances with which we are acquainted, composed, according to the most recent analysis, of about twenty distinct ingredients, the elements of all the diversified structures and secretions of the body. The relative proportions of the constituents of the blood are different in every individual, and in the same individual at different times. Age, sex, state of health, food, and many other circumstances, cause them to vary, and every variation affects in some manner the condition of the frame.

It has been already mentioned that loss of substance invariably attends the action of organs: it is for the purpose of compensating this loss that blood is required. Hence no function can be performed without the presence of the blood: the brain cannot feel, nor the limbs contract, without a due supply of this, which is therefore emphatically denominated the vital fluid. The apparatus by which it is distributed to every part of the body is the next subject to be considered.

This apparatus consists of two parts, the organ which communicates the impulse to the blood, and those which convey it to and fro. The former is the heart, the latter are the blood-vessels, which are divided into two classes, arteries and veins. The heart in man is a conical-shaped muscular body, possessing both elastic and contractile powers, and containing four cavities or receptacles for the blood, separated from one another by a most exquisite set of contrivances in the shape of muscular partitions and membranous valves. To these cavities the names right and left auricle, right and left ventricle, have been given; the functions of which, and of the blood vessels, we now proceed to explain.

Supposing the blood to be in the left ventricle, we will follow its course from that organ.

The muscles which compose the sides of this cavity are the thickest and strongest portion of the heart, a circumstance necessary to enable it to perform its function of propelling the blood into the arteries over the whole body. The left ventricle contracts four thousand times in an hour, and at each contraction forces into the great artery or aorta about two ounces of blood. The aorta gives off several large arteries, which, by their successive subdivisions, convey the blood to every part of the body.

Arteries are composed of three layers of membrane, which together form a tube of great strength and elasticity. It is by means of the latter quality that they assist in the circulation; by maintaining a constant pressure upon their contents, they regulate and render equable the flow of the blood. Arteries successively increase in number and diminish in size, each trunk dividing into two or more branches, and this subdivision proceeds until the ultimate arteries or capillaries are so minute as to be imperceptible to the unaided eye. These capillaries penetrate every organ and tissue, and are the immediate agents in building up structure, in conveying nourishment to the entire frame, and in performing the function of secretion. They terminate, it is supposed, in canals worked out in the substance of the various tissues, each of which,

*Tissue is the name given by physiologists to the various forms of matter of which the body is composed the principal tissues are the membranous, the muscular, and the nervous.

by means of its vital power, attracts from the blood flowing through it those particles with which it has a chemical affinity: bony particles are not deposited in the brain, nor the constituents of muscle in the bones:-each tissue receives those ingredients only of the blood of which it is itself composed. It is this conversion of blood into structure which constitutes the process of nutrition. At the same time particles which had formed part of the living structure, but have lost their vital properties and become noxious, being separated from the structures with which they had been connected, are poured into the blood, either to be conveyed out of the system or to be renovated.

Where the arteries terminate, the veins begin: the blood passes into them to be carried back to the heart. Veins differ in several important respects from arteries: they are more capacious, and though composed of an equal number of coats essentially the same in structure, are much thinner, and destitute of elasticity. The inmost coat of most veins is formed into numerous folds, which serve for valves and prevent the return of the blood.

Converging from all parts of the body, the veins at length unite to form two large vessels, the superior and inferior vena cavæ, which meet at the entrance of the right auricle of the heart, into which they discharge their contents along with the newly-formed nutriment, and thus the greater or systemic circulation is completed. The blood brought back differs widely, however, from that which was sent from the left side of the heart. In its course through the body it has undergone changes of a very striking kind. Instead of the bright scarlet hue which it possessed in the arteries, it is now of a deep dull purple colour; nor is the alteration in its essential properties less remarkable. Venous blood is not capable of maintaining either the organic or animal life; it is arterial blood deprived of its nutritious particles, and loaded with worn-out or noxious atoms collected from all parts of the body. That it is inadequate to support life is certain, numerous experiments having been made which conclusively prove that within four minutes after the supply of arterial blood is cut off, and venous blood alone is circulated in the body, life becomes extinct beyond the possibility of recovery.

Now, inasmuch as a quantity of blood equal to the total quantity contained in the system is propelled from the heart about twenty times every hour, it is evident that there must be some contrivance by means of which the vital properties of arterial blood are restored to venous blood, otherwise no animal could exist. What that contrivance is, is now to be explained.

The principal ingredients in venous blood, the presence of which deprives it of its nutritive qualities, are carbon and hydrogen, the former one of the most extensively diffused elements in nature, forming the basis of a great number of minerals and of most vegetables; the latter a gas, the lightest of known bodies, and one of the elementary substances into which all animal matter is resolvable. Carbon enters largely into the composition of our food, and thus gains admittance into the system, where it would soon accumulate to excess, and subvert the very foundations of the animal economy, but for the provision for its expulsion. The contrivance for restoring to venous blood the vital qualities of arterial blood, is simply one for removing from it the carbon and hydrogen with which it abounds. The manner in which this important object is accomplished is one of the most beautiful applications of chemical laws with which we are acquainted. The right auricle, into which, as already mentioned, the venous blood is discharged by the veins, injects it into the right ventricle, whence it is propelled into the pulmonary artery, which divides into two branches, one going to each lung. The lungs are two large oval-shaped bodies, composed of light cellular tissue, situated one on each side of the thorax or chest, with the walls of which they are in contact, the heart being in the centre. They are full of exceedingly minute cells, in which the subdivisions of the trachea or windpipe terminate, so that each cell has free communication with the atmosphere. On the inner surface of these cells the ultimate ramifications of the pulmonary artery are spread, forming a net-work of vessels, which, on account of its complexity, is called rete mirabile, the wonderful net-work. Thus there are two sets of vessels traversing the substance of the lungs in all directions, air-vessels and blood-vessels, the contents of which are brought into contact with each other in the airvesicles, or cells, above mentioned, which, though contained within so small a space, are so admirably arranged, and so numerous, as to afford, according to the most moderate estimate, a surface of 20,000 square inches. Here, also, venous is converted into arterial blood. That our readers may comprehend this change,

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