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the Thirty-nine Articles; that we have hitherto made the man a friend of the Establishment ? Can any one, reflecting on his own case, seriously beheve that this has been the origin of his preference for the Episcopalian Establishment ? If it has, then the effect has, we greatly fear, in most instances, long survived all recollection even of the cause. But the fact is sufficient. Every man knows that at childrens' schools the teacher, be he ever so closely connected with the Church, and ever so zealous to inculcate her doctrines, finds his time occupied in making his pupils learn to read; and that whatever they learn of catechisms and articles, they learn by mere rote, and as a method of reading and spelling Happily for the Church, men support her, at first, because the Law and the Government favour her---because their families have lived and died in her bosom--because they have attended her ordinances from their earliest years-before they went to school--during tbe intervals of school attendance--and wholly independently of their schoolmaster. They afterwards give her a more rational support from their reason, by turning towards the question those faculties which they have been enabled to exercise, that knowledge which they have been enabled to acquire by school education, at a period when their minds were too young for controversy, and when they never heard of its existence.

We shall close these observations with narrating a fact, illustrative of what has been stated respecting the necessity of teaching-without reference to any particular ecclesiastical system, if we would teach at all. It is doubly interesting, because it relates to Ireland and to the Catholic body, and speaks to us with a loud voice on perhaps the most important application of the new method, and one which promises the greatest har. vest of public benefit. A Lancasterian school had been established at Waterford—it was open to poor children of all seetsthe Scriptures, or extracts from them, were alone taught-and the Roman Catholics sent their children as freely as those of any other persuasion. This beneficent Institution had proceeded for some tịme, dispensing to no less than four hundred poor infants the greatest of earthly comforts, when a zealous . member of the Established Church unhappily had influence enough to procure the introduction of the Church catechism

; and instantly one half of the children were taken from the : school. Happily the Dublin school, arranged by Lancaster, is preserved on the original plan; and it appears from the Annual Reports, that as nothing but the Scriptures themselves are taught in it, the Catholic and Protestant poor derive from it, in common; the lights of knowledge and of religion.


For the Church as established in this country--we allude more especially to the Anglican Church, for happily our Scottish institutions have never been fruitful of such disgraceful con-. tentions--but for the Church of England, we cherish the utmost respect. We not only grudge her none of those rights wherewithal she is plentifully endowed-not only wish to see her safe from all disputes as to her title--all attempts to lay her low; but we go farther and would have her dignities and her honours secure:- We will have her to exalt her mitred front

in Courts and Parliaments;' and will view an enemy to the State in every one, who, either by open assault, or by secret treachery, or by the still more dangerous enmity of injudicious and disreputable friendship, would bring her rights or her power either into jeopardy or suspicion. Hence it is, that we view with more than common indignation the men whom we have now been occupied in exposing to the public; because in them we see at once the enemies of the Poor, and of the Church--of Education and of Religion--men who would bring ruin upon the Establishment, by opposing the most enlightened and disinterested attempt that ever yet was made, in any country, for scattering the blessings of knowledge and moral improvement among the more helpless classes of our species.

Art. II. An Inquiry into the Changes induced on Atmospheric

Air, by the Germination of Seeds, the Vegetation of Plants, and the Respiration of AnimalsBy Daniel Ellis. 8vo,

pp. 246. Edinburgh and London. 1807. Further Inquiries into the Changes induced on Atmospheric Air, &c. &c. . By the same, 8vo,

pp. 375. Edinburgh and London. 1811.

IN in every stage of our inquiries into the properties of surround

ing bodies, there is a certain portion of truth, which it is always in our power, by minute and accurate observation, to acquire; and when we have acquired this, our knowledge of the particular subjects investigated may be considered as complete ; at least till new instruments or methods of investigation shalt: bring new phenomena within the sphere of our observation.

But if, on the one hand, it is only by full and correct observe ation, that we are led to the discovery of permanent truth, 'so, on the other, it will be found, that'error of every kind is invariably referable to observation that is careless and imperfeeti Thus it is, that, in the investigation of causes, some phenomena are occasionally overlooked which materially influence a le


sult, and others admitted as essential to it, with which it is in no respect connected; that analogies and resemblances are sometinies conceived to exist between events, which are in truth extremely dissimilar; and that the wildest flights of fancy are sometimes permitted to occupy the place of those rational and legitimate hypotheses, which, if they are not the immediate anticipatious of truth, are at least highly instrumental towards its discovery.

Obvious as these remarks undoubtedly are, we fear that the class of inquirers who are chiefly interested in the work before us, have but too seldom been fully aware of their importance. The science of Physiology-regarding it, in its widest extent, as that which treats of the functions or properties of animals and vegetables-has always attracted a considerable share of attention ; and yet there is none which has at all times abounded in so much extravagant theory. Even at the present day, we believe that there is no branch of knowledge more imperfect; nor any which, amidst a great though slowly accumulated mass of curlous and important truths, still retains so large a proportion of what is vague, fanciful, and erroneous.

It would not perhaps have been uninteresting, to have en. deavoured to point out at length the causes which seem to have subjected this science in particular to such an imputation; but, for the present, we must content ourselves with observing, that we believe they may all be reduced nearly to the following That the various departments of the science have hitherto been considered in a manner too unconnected and irregular; and have been too little cultivated by persons capable of devoting an undivided attention to their investigation, and of studying all the functions of life in their actual connexion with each other, It is unfortunate, too, that Physiology has been regarded as the peculiar province of persons connected with the profession of medicine; for the most able and intelligent individuals of this class do not always cherish a partiality for physiological inquiries ; or, if they do possess any taste for such pursuits, they are usually prevented from prosecuting them with success, by the labour or inultiplicity of their practical duties. The truth indeed is, that, in the vast variety of phenomena exhibited by organized beings, anatomists, physicians, metaphysicians, chemists, opticians, and mechanical philosophers, have all found ample field for occasional investigation. Each have selected, for separate speculation or inquiry, those subjects which were most conformable with their habitual studies or occupations. To their talents and industry Plysiolo

is indebted for a large share of the established truth of which 's to boast; but, at the same time, we are obliged to impute to the partial views of these very men, the greater proportion of the error with which it abounds.


If any thing, however, can contribute to render an imperfect science speedily perfect, it is the publication of inquiries conducted on the plan of those which form the subject of the present article. We scarcely know any work in physiology, where an author has displayed a more extensive knowledge of every fact contributing, in the most remote manner, to elucidate the object of his investigation; in which, he has sought the opinions of others with more diligence, or stated them with more uniform candour; or where he has himself interrogated Nature, by experiments more judicious or more successful.

It is a fact, which has been long sufficiently known, that every thing which lives, whether animal or vegetable, requires, for the continuance of its life, a constant supply of fresh air. The great purpose of Mr Ellis's Inquiry, is to discover why it is that air is necessary to the vital existence of organized bodies. In the present volumes, he has particularly in view, to show the precise nature of the changes which the air suffers, from the action of animals and vegetables upon it; and in what manner those changes are effected. The original • Inquiry' was published in 1807; but the author has, since that time, not only been led, in obviating the very few objections which have been urged to his doctrines, to the discovery of some new and interesting facts, but has corrected his original views by various additional experiments. The result of the whole we shall endeavour to lay before our readers in as few and as plain words as possible.

In the human body, from the first to the last moments of its existence, we remark, that a certain quantity of air is alternately rushing into and out of the mouth and nostrils

. The chest, or thorax, is so constructed, that, merely from the elasticity of its sides, and the pressure of the surrounding parts upon them, it has a tendency to assume a certain permanent capacity or dilatation. * Accordingly, after death, when there no longer exists any counteracting cause, this is the capacity which it assumes and retains. We may call it the natural state of the thorax. In the living body, however, it is found that, by the action of the surrounding muscles, a further enlargement of the chest, beyond its natural state, may be produced. As soon as this dilatation commences, it is obvious that a sort of vacuum must be formed between the sides of the thorax and the lungs. A curient of air, therefore, immediately flows through the windpipe into the air-cells of the lungs, and gradually distends these or sans, in proportion as the cavity containing them is increased.

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This constitutes what is denominated Inspiration. The quantity of air which is inhaled, in any single inspiration, is of course determined entirely by the extent to which the chest is dilated. In individuals who are healthy and at rest, inspiration consists , merely of a gentle enlargement, produced by a partial contraction of the diaphragm; and sucli may be termed an Ordinary Inspiration. The quantity of air, which rushes into the lungs during an inspiration of this kind, is very different in different individuals, according to the size of their chests, or the extent to which the diaphragm contracts, in the inspirations of each. It has been variously estimated, in adults of a middle stature, at 13, 17, 20, 35, and 40 cubic inches; affording 25 cubic inches

But all these calculations have not been founded on equally satisfactory data. Dr Menzies's experiments alone, which estimate the average bulk of an ordinary inspiration at about 40 cubic inches, seem to have been performed in an unexceptionable manner; and we place the more confidence in his calculation, that we have found it to correspond with some late experiments of our own. In larger inspirations, the thorax is increased in all directions; and the average bulk of air, at temperature 60° Fahrenheit, which is inhaled by the utmost possible inspiring effort, or by what may be called an extreme inspiration, is probably about 130 cubic inches. After previous enlargement, the cavity of the thorax


be diminished by the pressure of the abdominal viscera, the elasticity of the parts with which the ribs are connected, and the muscles which pull these bones downwards, exactly to its natutural capacity, or even considerably below it. When the diminution commences, the lungs are compressed; and the air, being thus forced out of their cells, escapes by the trachea and mouth. This constitutes Expiration. In health, and during rest, it consists of a reduction of the thorax to its natural state only; and this seems produced merely by the compression of the relaxed diaphragm, and the elasticity of the cartilages and softer parts affixed to the ribs : consequently, the quantity of air expelled is exactly equal to the quantity previously inhaled. Such may be called an Ordinary Expiration. In all larger expirations, where the chest is compressed below its natural state, the compression is produced and sustained entirely by the action of powerful muscles, drawing dowil the ribs, and forcing the diaphragm upwards; and, as soon as these muscles cease to act, the thorax returns to its natural state again. We are inclined to think, from experiment, that the quantity of air which, on an average, is expelled by an extreme expiration, after a previous extreme inspiration, is about 260 cubic inches. It is to be re


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