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In proceeding to consider the sacred require no ability at all. He should duties of the Pulpit, I enter a wide fairly invite a patient and candid field of discussion. Did I imagine hearing for them, point out the fallacy that the ability requisite for the pulpit of their reasoning, the absurdity of consists only in ready quotations from their conclusions, and the dreadful scripture, fluency of speech, inculca- consequences of a belief in them; for tion of certain dogmas, or violent de- they require but a reading to be disclamatic against opposite parties ; proved ; -write them down in an hothen would the task be easy, and nourable and manly mode of warfare, sterling talent useless. Then might at once the contest of truth, the power the presumptuous scribe of ignorance, of argument, and the cause of justice. or the ardent devotee of fanaticism, This requires no feeble display of inassert his undisputed claim to hold a tellectual ability ; but though the place with those pre-eminent in learn- labour may be arduous and wearisome, ing and piety. The divine ought to TRUTH still remains the same ; and possess not only wisdom, but the pro- though error may seem to usurp her foundest erudition. An acquaintance place awhile, and obscure her brighter with the English language only, is not lustre, yet the penetrating and unsuficient, but a knowledge of the ori- daunted mind of man may explore ginal tongues is highly important, and the darkened regions, and lead her indispensably necessary. Biblical un- forth, seated her snow-white derstanding, and the ordinary talent throne, the unsullied goddess of the to expound it, are but the two first intellectual world. steps to ascend the steep and craggy Another of the requisite qualificamountain. A critical study of the tions for the pulpit, is a well-grounded scriptures is a necessary qualification; acquaintance with the feelings and for without it, where is the fixed and passions of human nature. The diconscientious code of theological doc- vine should not consider his ministetrines which they are to promulgaterial labours at an end, when the disfor the benefit of others ? Where is the course is concluded ; but should go treasury of argument which ought al- round to the private houses of his ways to be in store, ready for discharge congregation, and diligently enforce against the bold invaders of religion the practical lessons of the gospel, and of morals? Or how are they to his sole aim being to moralize the life, teach, if they have not been taught? and to fit the soul for eternal felicity,

The divine has to encounter diffical- adapting himself to the particular ties of every kind, and when he meets capacities of each individual. He with foes, they are of the most formid- should be unwearied in his exertions able description. The adversaries he to carry the effect of his doetrines and is opposed to in the discharge of his precepts to the hearts of his hearers, ministerial functions, are not merely never leaving his object till he reads professional ones, but personal, and in the eyes of his congregation that generally rancorous enemies; and the desired impression is made. Force which require all the talent and energy of argument, bold and energetic lanof man to oppose and to baffle. Every guage, historical and descriptive illusthing that is levelled against the reli- tration, and eloquence of arrangegion of God, it is bis bounden duty to ment, are so many means, which the attack, and indefatigably pursue, till divine ought to possess, to reach the destruction shall have overtaken it. hearts of his auditors. Whatever is I do not say that the divine should calculated to please, is adapted to attempt to crush by force all that he persuade ; and eloquence is, perhaps, may consider hostile to the doctrines a most efficient way of attaining which he professes to inculcate; or, this purpose. Eloquence, which is because he shall see the circula- nature's proudest jewel, steals imtion of the productions of a Paine, perceptibly on the mind, and proor any other infidel writer, that he claims her power irresistible. No sball endeavour to destroy them with profession affords so great a scope for out a hearing-without a trial-with- this invaluable talent as the pulpitout a reading ? No! Much as I detest no situation demands it more imperaand abhor such unchristian and immo- tively. ral principles, I would say, this would It is said of the celebrated Dr. bę dastardly work indeed: this would | Chalmers, of Glasgow, that he seldom 509

Chemical Essays.



leaves an idea till he completely ex- | and runs through the confined world hausts it in language. This may ap- of time, to Heaven's unmeasured pear an useless mode of preaching; space. but I apprehend it is a most effectual

Your's, truly, one, when we consider the diversified

March, 18. 1822. T. Wclasses of persons, and different degrees of understanding, which compose all religious congregations, inas- CHEMICAL ESSAYS,—BY STUVIOSUS. much as such a method is pre-emi

( Continued from col. 350.) nently calculated to strike all the auditors with pleasure and with con- Essay 4:—On the Composition of the At, viction, though at various periods. mosphere, and on the Chemical and The power and value of eloquence are Physical Properties of Air. incalculable. See a most striking excmplification of it in the case of The term atmosphere is derived from Ligarius. Cicero had undertaken to two Greek words, and signifies a body plead his cause ; and Cæsar, well of vapour in a spherical form.. By knowing the amazing effect of his this term, we import the elastic, invi. splendid eloquence, resolutely deter- sible, inodorous fluid, consisting of mined, before leaving his apartments, the air properly so called ; together that nothing whatever should save the with the vapours, electric fluids, life of Ligarius. But when Cicero clouds, and unknown bodies, which began, his speech bad such a variety are continually floating in it, inclosing of pathos, so irresistible a charm, that the earth on every side, extending to Cæsar's colour often changed, and his an unknown height, and partaking of mind became torn by conflicting pas- all its motions, annual and diurnal. sions. At last he was so extremely It is the medium in which we live, affected, that his whole frame trem- and without which we could not bled, and he let drop some papers out exist. of his hand ;-thus subdued by the The ancients were totally unacforce of eloquence, he acquitted Liga- quainted with the properties and eomrius. But to the point.

position of the atmosphere, and the The duties of a divine are more greater number of them considered the awful, and more responsible, than blue colour of the sky as essential to those either of a barrister or a sena- it, and never once thought of this tor, and it is this responsibility which being owing to the vapours which are demands a greater proportion of talent, continually mixing with it, and which -a more enlarged expansion of intel have the property of reflecting the blue lect. He stands between earth and rays more copiously than any other, heaven, as the messenger of God and as first proved by the ingenious and the herald of his people: be points the immortal Saussure. road to glory and immortality; We are indebted to the celebrated paints the gloomy horrors of the tomb; Boyle for the discovery, that the atand leads his auditory to take a view, mosphere always contains two distinct an appaling view, of the wide yawning substances, viz. air, which is a comgulph, anxious, as it were, to receive pound, consisting of Oxygen and Nithe deluded prey of the impious and trogen Gases, and Water in a state of profane. He has the guardianship of elastic vapour. Since his days, philoboth soul and body entrusted to his sophers have proved beyond a doubt, care; the happiness and interest of that the atmosphere always contains a their existence in this world, but, small proportion of Carbonic Acid above all, their final and consummate Gas; and these we have every reason destinies in the world to come. Faith- to suppose are the only substances fully to discharge the important du- that are essential to its constituties imposed upon the divine, how tion. vast, how superior, ought to be his From what has been already adability. The barrister and the senator vanced, it follows, that the atmosphere have to do only with mortality, but consists of the four following permathe divine has to do with immortality. nently elastic fluids, viz. Oxygen and The spheres of operation for the bar- Nitrogen Gases, which constitute the rister and senator are bounded, but greatestand most important parts of the those of the divine are unbounded, atmosphere; Carbonic Acid Gas; and


Water in a state of vapour:-Atmo- quantity of aeriform fluid, chiefly spheric Air. The ancients considered Nitrous Gas, which would alter the the air we breathe, as an element, or result. By this mode of analysis, I simple homogeneous fluid, and this have always found 100 parts of Atmoopinion was universally maintained spheric Air to be composed of 22 parts till about the end of the eighteenth of Oxygen Gas, and 78 parts Nitrocentury. We are indebted to the la- gen Gas. This differs somewhat from bours of Dr. Priestley, Sheele, and the determination of Davy and others, Lavoisier, for the discovery that air who found the component parts of is a compound, consisting of Oxygen Atmospheric Air to be 21 Oxygen Gas, and Nitrogen Gases. We are not and 79 Nitrogen Gas. acquainted with any means by which From the experiments of a great to abstract the Nitrogen from its com- number of philosophers, it is now bination; Atmospheric Air, there- proved beyond a doubt, that the diffore, can only be analyzed by expos- ferent degrees of the salubrity of Ating it to the action of such bodies as mospheric Air do not depend upon will absorb its Oxygen Gas. The any difference in the quantities of its Nitrogen Gas will then remain behind, constituent parts as formerly supposand the proportion of Oxygen Gas ed, for Atmospheric Air always conbe ascertained, by the diminution of tains exactly the same proportions of bulk; by which means we shall be Oxygen and Nitrogen Gases, in all enabled to determine the exact quan- seasons, and in all situations, near tity of the two gases, in a given bulk the earth's surface, and at the greatest of Atmospheric Air.

heights which the industry of manhas The instruments employed for this been able to penetrate. - Besides the purpose have received the name of two gases already mentioned, and Eudiometers; the first of which was which form the bulk of our atmoconstructed in consequence of the dis- sphere, it has been supposed to concovery of Dr. Priestley, that when tain a very small proportion of HydroAtmospheric Air is mixed with Nitrogen Gas; and it has been proved very gen Gas over water, the bulk of the satisfactorily, that Carbonic Acid Gas mixture undergoes a very rapid dimi- always exists as a constituent part of nution, in consequence of the combi- air; and we are now well acquainted nation of the gas with the Oxygen of with the means by which to detect the the air, and the absorption of the presence of this gas, so that its exNitric Acid, thus formed by the wa- istence as a constituent part of Atmoter. This mode of analyzing Atmo- spheric Air is now proved beyond the spheric Air being liable to many er- least shadow of a doubt. rors, has now fallen into disuse. Since

The proportion of Carbonic Acid the first construction of Dr. Priest- Gas in air, was, till within a few ley's Eudiometer, others have been years ago, estimated at 1 part in 100, proposed by De Marti, Berthollet, but from the experiments of Mr. DalHumboldt, Sequin, Volta, &c. ton, it seems probable, that it does

The Eudiometer now in general use not amount to more than 1 in 1000. is one invented by the ingenious Mr. We are indebted to Dr. Black for the Davy, which, for simplicity, expedi- first step in the discovery of Carbonic tion, and accuracy, stands unrivalled. Acid Gas as a constituent part of This consists of a small glass tube, Atmospheric Air. As soon as the air divided into 100 equidistant parts. of our atmosphere was known to be a The tube is to be filled with Atmo- compound body, it became an immespheric Air, and immersed into a ves- diate object of inquiry, whether the sel, containing a concentrated solu- gases which enter into its constitution tion of muriate or nitrate of iron in are merely mechanically mixed togewater, strongly_impregnated with ther, or enter into chemical combinaNitrous Gas. The tube is to be tion. With the exception of Sheele, moved a little backwards and for- philosophers seem to have considered wards through the solution, to favour the air as a mechanical mixture; but the absorption and condensation of Bertholett, Davy, Humboldt, and the Oxygen Gas, which will be com- other chemists, have demonstrated pleted in a few minutes. The state of that it is a chemical compound, which the greatest absorption must be mark- opinion is now adopted by almost ed, as the mixture always emits a | every chemist. Mr. Dalton, however,


Chemical Essays.


has published an essay in the fifth called inspiration, and is always ravolume of the Mancbester Memoirs, in ther longer than the latter, which is which he considers the general atmo-called expiration. The interpal sursphere as composed principally of face of the lungs is lined with a transfour particular gases, namely, Oxygen parent and delicate membrane, which, Gas, Nitrogen Gas, Carbonic Acid according to Haller, is not more than Gas, and Vapour; totally unconnect the thousandth part of an inch in ed with each other, the particles of thickness, but whose surface is said the one not acting on the particles of to be equal to the external surface of the other.

the whole body, that is, generally Philosophers have long known, that speaking, about 15 square feet. On the particles of elastic fluids repel this very fine and sensible menibrane, each other with a force reciprocally a great number of blood vessels are proportional to the distance of their distributed ; and through these véscentres from each other. Now Mr. sels, the whole mass of blood circuDalton is of opinion, that this pro- lating within the body is successively perty only belongs to homogeneous propelled, and exposed through the elastic fluids, and that in a mixture of medium of a thin pellicle, by far more two or more elastic fluids, the parti delicate than the finest cambric, to cles of the one do not either attract or the influence of the Atmospheric Air, repel those of the others; and applying with which the air-cells of the lungs this property to the Atmospheric Air, have free communication, by means he endeavours to prove by this very of the aspera arteria, trachea; or ingenious hypothesis, that the density windpipe. and elastic force of each gas at the We find by experiment, that the surface of the earth, are the effects of quantity of Atmospheric Air respired, the weight of the atmosphere of that differs very much in different men, as gas only, the different atmospheres also does the number of respirations not gravitating upon each other. in any given time. According to Dr.

Chemists have started many objec- Kiell, by the rise of the sternum in tions against this very ingenious and man, and the descent of the diabeautiful hypothesis, which is indeed phragm, room is afforded for 42 cuevery thing but true. The absolute bic inches of Atmospheric Air at every necessity of Atmospheric Air to respi- inspiration; and that a forced inspiration, is acknowledged by every ration will give room for more than body, and it is also well known, that twice this quantity. In regard to the no other gaseous body can be substi- number of respirations in a minute, I tuted for it. We have already demon- myself make 18 at an average. I find strated that the Atmospheric Air is that a young boy, upon whom I have composed of at least three gases, two made very frequent experiments, alof which are destructive to animal ways breathes 22 times in a minute. life; hence it follows, that only one of Another boy upon whom I have these gases is useful to respiration - also made experiments, only breathed this is the Oxygen Gas, to the pre-16 times. Dr. Hales reckons the sence of which we are warranted, both number of respirations at 20 in a mifrom the effects of respiration, and nute. Now, supposing that a man at from the changes which blood under an average breathes 20 times in a goes when exposed to the influence of minute, he will make 1200 inspirathe atmosphere, to attribute all the tions, and as many expirations, in an changes observable in the colour of hour; consequently the number of the blood.

respirations in the 24 hours will Man, and indeed almost all ani- amount to 28,800. And again, if we mals, are provided with lungs to admit that 42 cubic inches of air are breathe through, and their lungs are received into the lungs at each inspilodged in the chest. They are also ration, we shall see what a vast quanprovided with a diaphragm, by which tity of Atmospheric Air is respired in their respiration is performed. Respi- the 24 hours, amounting to no less ration consists in the alternate taking than 1,209,600 cubic inches. in a certain quantity of air, the lungs After the Atmospheric Air, inhaled expanding to receive it; and throwing by inspiration, has remained for a cerit out again, the lungs contracting to tain time in the pulmonary structure, expel it. The former of these is l it is again expelled, somewhat dimi

nished in quantity, and greatly altered exposed to the influence of the Atmoin its composition. According to Dr. spheric Air becomes florid on the exteMenzils, the diminution of air in the rior of the crassamentum, but its intelungs amounts to about one twentieth rior parts remain nearly black. If, part. We find exactly the same pro- | however, the interior parts of the portion of Nitrogen Gas, it is true, but crassamentam be placed uppermost, its Oxygen has suffered a great dimi- they will assume a florid scarlet conution, a small quantity of which is lour, in common with the former exabsorbed by the blood ; the remain-terior parts of the crassamentum. If der, uniting with the Carbon of the either air or Oxygen Gas be injected blood, forms Carbonic Acid Gas, into a tied vein, the blood, which was which together are expelled by the black, will be changed to a florid scarefforts of respiration, along with a let colour. The dark purple blood of quantity of an aqueous vapour, which, the lungs then is changed to a vermiduring very cold weather, not unfre- lion colour by the absorption of Oxyquently condenses in its passage gen, but I have demonstrated that the through the mouth and nostrils. same effect is produced upon blood

In my Essay on Carbonic Acid Gas, when out of the circulation ; we are I have demonstrated, that a quantity not warranted, therefore, to attach too of th gas is emitted during respira- much importance merely to the change tion ; now this quantity is consider- of colour; although there are many ably greater than was contained in the people who suppose that the red verair inspired, from which it follows, milion blood alone possesses the prothat it has been produced from a com- perty of supporting the life of those bination of the Carbon of the blood parts through which it circulates, but with the Oxygen which the respired this is much more unreasonable than air is found to have lost. The quan- to suppose the vermilion colour of the tity of Carbonic Acid Gas contained blood is an essential character. in the air expelled by the efforts of re

(To be continued.) spiration, may be ascertained by exposing the respired air to the action of a caustic alkali. The diminution of THE MUTINY.BY A PASSENGER. the Oxygen Gas may be ascertained by means of Davy's Eudiometer; by In the summer of the year 18, I was means of which, we shall also discover the only passenger on board the merthat its Nitrogen Gas has not suffered chantman, Alceste," which any diminution.

bound to the Brazils. One fine moonWe have now considered the chan- light night, I stood on the deck and ges in the Atmospheric Air, produced gazed on the quiet ocean, on wbich by respiration; but it still remains for the moon-beams danced. The wind us to consider what are the effects of was so still that it scarcely agitated respiration upon the blood itself. The the sails which were spread out to inmost obvious effect of the Atmospheric vite it. I looked around, it was the Air is, its changing the dark colour of same on every sidema world of wathe blood, to a florid scarlet colour. ters, not a single object diversified the The experiments of Mr. John Hunter, view, or intercepted the long and Dr. Goodwin, and others, made upon steady glance which I threw over the dogs, have sufficiently proved that ocean. I have heard many complain Oxygen Gas is really imbibed by the of the sameness and unvarying uniforblood in its circulation through the mity of the objects which oppose

themlungs, and that it is owing to the ab- selves to the eye of the voyager. I sorption of Oxygen that the change of feel differently; I can gaze for hours, colour in the globules of the blood is without weariness, on the deep, occuoccasioned. If we receive dark ve- pied with the thoughts it produces. I nous blood in vacuo, we shall find that can listen to the rush of the element it still remains of a dark colour ; if we as the vessel cleaves it, and these expose it to Nitrogen Gas, or Carbo- things have charms for me which nic Acid Gas, it will still remain the others cannot perceive. same;

if Atmospheric Air be admit- I heard on a sudden a noise which ted, it will become bright; and if Oxy- seemed to proceed from the Captain's gen Gas be admitted, it will assume cabin, and I thought I could distina beautiful vermilion colour. Blood guish the voices of several men speaks



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