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this gas out of the cells of the lungs, it combined only with a small portion of it, -the remainder passing back into the cells again; while others thought it more probable, that no more was absorbed by the blood from the cells, than this fluid permanently retained.

This rapid and casy transmission of gases through the sickes of the cells and vessels of the lungs, which is the common foundation of all these theories, Mr Ellis maintains, is not only totally devoid of proof, but, if sound philosophy only allows us to conjecture, respecting phenomena unseen, from what we have experienced of similar events actually perceived, that it is not legitimate to entertain it, even as an hypothesis. Dr Lower had indeed observed; that when dark-coloured blood was brought into contact with atmospheric air, it assumed a florid coTour; and various other physiologists after Priestley, had proved that this, or any other air containing oxygen, so exposed, lost part of its oxygen, and gained carbonic acid. Lower had also demonstrated, by experiments on quadrupeds, that the change of colour from modena to a scarlet red which the blood underwent in the lungs, depended entirely on the presence of fresh air in their cells : Andi Priestley found, that when a qnantity of dark-coloured blood was tied up closely in a moistened bladder, and hung in the air, the whole lower surfaee of the blood acquired a coating of a florid red colour, as thick as if no bladder had intervened. From all this, it had been inferred, that, during respiration, either some part of the air passed through the sides of the cells and vessels of the lungs into the blood, or that something was given out by the same course, from the blood to the air, so as to alter the colour of the one, and the composition of thie other. But, without' denying that, in these instances, the change of colour in the blood depended on the presence of atmospheric air, or of air containing oxygen, Mr Ellis has shown, by the most satisfactory experiments, that, in the case where the bladder intervened; neither did the air afford any portion of its gases to the blood; nor did the blood communicate any matter to the air. Thus, when he put a quantity of black blood into a small bladder, and suspended it in a glass jar containing 13.1 cubic inches of atmospheric air inverted over mercury, he found that the blood soon reddened ; thiạt, at the end of two days, the whole of the oxygen of the included air had disappeared--but that an equal quantity of carbonic acid had been formed. Hence it is obvious, that as all the oxygen which had disappeared was converted into carbonic acid, none could have penetrated the bladder, or combined with the blood. On

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the other hand, when Mr Ellis suspended, in the same manner, bladders filled with water, or bladders empty, but moistened, in jars of atmospheric air, the oxygen was equally found to be converted into carbonic acid. Since, therefore, it thus appears that a moistened bladder is of itself capable of affording carbon to form carbonic acid with the oxygen of the air, there is no reason for supposing, that the carbon is derived from any other source, where the bladder is filled with blood; and the conclusion seems irresistible, that when dark-coloured blood is reddened by the air, through the sides of a moistened bladder, the air yields no oxygen to the blood, nor acquires from it any carbon ; but the carbon of the bladder, by its combination with the oxygen of the air, passes into the state of carbonic acid gas. The doctrine, then, of the entrance of gases into the blood from the air cells of the lungs, can no longer be regarded as receiving the best support froin Priestley's experiment. But although the result had been otherwise, and the direct passage of something through the bladder had been unequivocally proved, we should still have been disposed to maintain with our author, that it would not necessarily follow, that any similar transmission of air took place through the sides of the cells and vessels of the lungs. On the contrary, we regard it to

a fact, as well established as any in Physiology, that no part of the body, provided with vessels, however delicate it may be, has ever been observed to permit the smallest quantity of any kind of fluid to permeate through it, as long as the circulation continues in that part; though, as soon as death has taken place, transudation goes on in all textures with the utmost facility. We should not, therefore, be entitled to infer, merely because a dead Diverse

may seem to allow of the transmission of air, that the cells and vessels of the living lungs are equally permeable to that fluid.

Mr Davy had concluded from experiment, that 71 or 93 cubic inches of nitrous oxide might, in the short period of half a minute, be absorbed by the venous blood, through the moist coats of the pulmonary veins. Our author's observations, alone, would have left very little doubt in our minds, that, in these expe*timents, though a portion of gas had disappeared from the air

had passed into the vessels of the lungs. But we holder have, ourselves, found, by repeated trials with nitrous oxide and atmospheric air, that, when a given quantity of either of these is frequently breathed, the desire, or sympathetic stimulus to inspire, becomes gradually so strong, and the expirations proportionally so short and restrained, that, at last, when the ex

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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 believe 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 hare 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 time, 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 plans 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 Animals, By 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 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, te 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 shall bring new phenomena within the sphere of our observation.

But if, on the one hand, it is only by full and correct observo ation, that we are led to the discovery of permanent truth, 50, on the other, it will be found, that error of every kind is invariably referable to observation that is careless and imperfeet." Thus it is, that, in the investigation of causes, some phenomena are occasionally overlooked which materially influence a re

sult,

$ult, and others admitted as essential to it, with which it is in no respect connected ; that analogies and resemblances are sometimes 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 anticipations 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 endeavoured 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 connect. ed 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, playsicians, 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 Pluysiology is indebted for a large share of the established truth of which has to boast; but, at the same time, we are obliged to im

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