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forging, and converting iron : almost, if not refineries for iron, the modern art of war all, the processes through which iron has made heavy demands upon that passed in the arts were then effected by the article. In order to produce cannon, use of this vegetable coal, and the ancient bombs, muskets, pistols, bayonets, swords, forests which abounded in this and in almost cannon balls, grape shot, and all the every country where iron ores were found, munitions of modern warfare, what an afforded a plenteous supply of refuse timber enormous demand must be made upon for all these purposes, and many others in the article of mineral coal! Chain-cables the arts. But the ancient forests are cut for ships and other vessels, as well as chain down and consumed; and the difficulty of rigging, both fixed and running, are procuring this species of fuel became, modern additions to the consumption of within the last twenty years, so great in coals and iron. And the increase of ships these islands, that many of the owners of has increased the demand for anchors, forges were compelled to have recourse to bolts, braces, strops for blocks, stanchions processes which admitted of the use of | and irons therein and thereon, exceedingly. mineral coal in their refineries; wherein Iron railways for carriages, iron corses they convert pig or cast iron into bar, and waggons, iron cranes and chains plate, or hoop iron. And such is the re thereto, and iron axles, bushes, and tira action upon charcoal, that, since these for wheels, have also increased with the methods have been almost universally increase of carriages; and anvils, vices, adopted in the mineral districts, instead of hammers, and other iron tools, with the its being difficult to procure a sufficient increase of workmen. Machinery has supply of charcoal for the uses of the arts, grown up amidst the manufactories of these the refuse timber or cord-wood which islands into a vast colossus-huge in the every wood affords, whenever a fall of extreme; and, notwithstanding its enortimber is made therein, is become a drug in mous growth during the last thirty years, the market. But such are the immense from the vigour of its increase from year quantities of iron which now pass through to year, it yet seems only a boy, compared the refineries, that if the ancient mode were with the manhood it is aspiring after. re-adopted, in a single year charcoal could Those immense limbs of this giant, which not be found to supply a tithe of the de- are in use for forging, slitting, rolling, and mand, if even, instead of charring the drawing iron, for throwing silk, for spinrefuse only, the whole of the falls of timber ning cotton, flax, and wool, for weaving, throughout the mineral districts, however shearing, and dressing calicoes and cloth, valuable for other purposes, were not for grinding corn, and dressing flour, yea, charred also; and even these would not for thrashing corn from the ear and winsupply any thing like a permanent demand nowing away the chaff, and for almost for charcoal.

every purpose of life, all of which are There are foreign nations, even in adding in size and multiplying in number Europe, where the forest timber amply daily, astonish the thinking mind while it suffices for all the purposes in the manu- contemplates them, and leads it to exclaim, factories of iron, to which we apply mineral “ Where will these additions end ?” coal; and some of these, for instance Last, but by no means least, is the Sweden, Norway, and other districts steam engine : a machine which, like a bordering upon the Baltic sea, produce mushroom, or rather a fungus, has grown annually great quantities of iron, as well up in a night, to a size wonderful to as other metals. How long, even these behold. Had we nothing else, the alarmcountries may derive supplies of vegetable ing consumption of coal in the use of these coal from their forests sufficient for the machines, which has grown up within manufacture of iron therein, especially if the last half century, and is growing to their manufactories were to increase in any the present hour with a vigour which thing like the rapid progression of those in threatens to ingulf the whole coal strata of Great Britain, is a question difficult to these islands; had we nothing else, I repeat, answer. But whenever a period arrives steam engines alone are sufficient to deal when the manufacture of iron outruns the alarm, as to the future comforts of mansupply of vegetable fuel, then, like Britain, kind, by their prodigal consumption of this these countries must immediately resort to necessary of life, coal, therein, throughout the use of mineral coal, or otherwise they Great Britain: for Great Britain is a land must, of necessity, contract their manu wherein domestic comfort cannot be factories.

secured without the use of mineral coal, In addition to the immense consump-during three-fourths of the year, in every tion of coal in the smelting furnaces and habitation of man. For blowing furnaces

and refineries, for working forge hammers, whom, like ourselves, are men; and, thererollers and slitters of iron, for drawing fore, must be a work of humanity worthy wire, for grinding, polishing, and burning of the most exalted mind. iron and steel into mercantile articles, for In general, immediately upon the terturning those immense masses of machinery mination of the bold escarpments of the which throw silk, spin flax, wool, and chalk strata in the eastern counties of cotton, and weave webs of sundry kinds, England, a level stratum is found, and to for pumping water out of mines and low this succeeds a limestone stratum, the grounds, and pumping water into canals, | planes of which are considerably inclined docks, or reservoirs, for drawing waggons to the eastward. Wherever this limestone upon rail roads, for grinding and dressing strata exists, I am persuaded coal strata corn, and a thousand other purposes, steam exists also, although at great depths beneath engines are growing up, until the smoke it; and I have no doubt succeeding ages whieh issues from their towering chimneys will find means to extract the coal from covers the land. But this is not enough; this strata, deep as they are. What a their smoke already covers our navigable subject for the contemplation of a mind rivers, and it aspires after the dominion of formed in the mould of humanity! Our the sea; for, if we may predict from the fellow-men must descend into an abyss of past what the future will achieve, their matter, to the depth of a thousand, if not smoke will cover the oceans also. And twelve hundred yards from the light of the as though all the means already enume sun and the salubrious atmosphere, to rated, and full as many more which might | sweat in darkness amidst sulphureous be added, were not enough, we have emanations and pestilent gases, from day to another novelty, whereby the consumption day, for their daily bread, to send up of coal is insured daily ; viz. that of extract- mineral coal for smoke and vapour! ing gas from coal, in order to give light

(To be continued.) within our houses, churches, public buildings, shops, and manufactories; and even without, along our streets and highways;

ESSAYS ON PHYSIOLOGY, OR THE LAWS OF for, in order to procure this gas, we con

ORGANIC LIFE. sume coal in heating the retorts which pro

(Continued from col. 553.) duce it. , I have been led into this digression, if | ESSAY 11.

on if Essay IX.-On Animal Temperature, digression it may be deemed, because it is

· Instinct, the geometrical progression of our coal In our last essay, we noticed the influence mines, which rings the alarm-bell inces which the cutaneous system exerts upon santly in our ears; seeing, to these mines the body, as to the regulation of its temmay be referred almost all the reasonings perature, allowing at the same time that which constitute the article that precedes the muscular, nervous, and digestive organs this, and almost all the dangers to which concur also by their action, in this object; miners are exposed in these islands. As their operations tending to enable the body one means, therefore, of averting the evils to resist to a certain point, the great natural to which so large a proportion of our depressions which take place in the temfellow-men are exposed as miners now are, perature of the atmosphere around us. and ere long will be, it is not too much With regard to the muscular system, it to attempt, at least to hang a drag upon must be sufficiently evident to all, that its the rapid progression of coal consumption, | influence is very considerable, for we know by calling the attention of the public at from common experience, how necessary, large to this enormous and yet growing under exposure to a cold temperature, evil. It is a question well worth a thou vigorous muscular action, as running, sand experiments, if even these issued in a walking, &c. becomes, to maintain the solution thereof, Is there no other mode of body at its natural standard, while, on producing artificial heat, but by means of the contrary, if the body be suffered to the fuel which inflammable substances remain inactive, even for a short period, yield ? Could our able chemists be bet the natural temperature begins to decline, ter employed than in attempting such and sensations of pain (preceding numba discovery? In this age of discoveries, ness and loss of vitality) proclaim the when chemistry has attained such vantage- necessity of exertion to which they arouse ground, is it too much to suppose some us.--During a state of profound rest, as in such discovery may be made by them ? sleep, there is naturally a slight decrease Such a discovery would certainly save from of temperature, hence animals instinctively danger, and even death, multitudes, all of retire to a warm retreat, or assume such 115.-VOL. X.

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positions, in sleep, as are best calculated | a less capacity for caloric than fluids, and for protection against the cooling influence | fluids than aëriform bodies ;-if therefore, of the surrounding atmosphere. -Man too, a solid become fluid, or a fluid aëriform, refining on the dictates of instinct, seeks it absorbs a great portion of caloric, as even here, not merely to satisfy nature, requisite for its change to such a state, but to gratify his luxury, he robs the swan while its temperature remains precisely the and the eider-duck of their down, to pam- same :-And on the contrary, if a liquid per his enervating indolence. The nervous become solid, or an aëriform liquid, the system also exercises great control over the | caloric which it before contained being animal temperature, inasmuch as it influ- | more than sufficient to preserve it merely ences respiration, and through this again, in its former temperature, raises it consethe action of the heart and arteries ;-hence quently to a higher degree, which of course all the organs of secretion, diversified and is quickly reduced by the contact of surnumerous as they are, participate in the rounding bodies. impulse. In this view we may regard the Now, Dr. Crawford endeavours to shew actions of the digestive organs, first as by experiments, that arterial has a larger affording a supply by means of which the capacity for caloric, than venous blood, vital energy is recruited ; and secondly, as and common air than carbonic acid ; by the operations themselves by which the when, therefore, the carbon of the venous extraneous matter is so converted as to blood unites (in its passage through the become part and parcel of the living body, lungs) with the oxygen of the atmosphere, they affect its temperature,

to form carbonic acid, it must follow that The changes which take place in the the temperature of the carbonic acid so temperature, in morbid states of the body, formed, must be increased, its capacity for certainly merit attention. There are seve- caloric being less than that of the atmo. ral instances on record, in which indivi. spheric air, but the blood also having as. duals labouring under madness, have lain sumed during this operation its arterial exposed to so severe a cold, as to freeze character, has acquired a greater capacity the water or milk provided for them, into than when venous, and consequently it aba mass of ice, without suffering in any sorbs the caloric disengaged from the carapparent degree the consequences which bonic acid.The arterial blood is not now might have been anticipated.

sensibly warmer than it was, because the It would however, be foreign to the addition of caloric is only sufficient to nature of our plan to follow up this branch preserve it of its previous temperature. of the subject ;-we shall therefore pro The arterial blood now circulates through ceed to notice the theory of animal tem the system, and becoming venous, its caperature. Whence, or how does the tem pacity for caloric becomes at the same time perature of animal bodies originate? diminished,--and the caloric, before latent,

An ingenious hypothesis on this subject is consequently evolved, and so keeps up the was devised by Dr. Black, which, how | natural temperature of the body, supplying ever, has met with formidable objections, the continual abstraction occasioned by the totally subversive of its truth.-These colder medium that surrounds us ;-while objections Dr. Crawford subsequently the blood, returning to the heart and thence attempted to obviate; and his theory, which to the lungs, acquires a fresh store, to be may be accounted an improvement upon again exhausted and again renewed till that of Dr. Black, is still not without its life ceases. supporters.

Besides this, there is also another source To explain it as briefly and clearly as from which a portion of caloric is derived, possible, it must be observed in the first and which depends upon the principle we place, that different substances have differ have before stated,-- viz. that fluids, when ent capacities for caloric,—that is, if two becoming solid, impart to bodies in condifferent substances be placed for a given tact, their superabundant caloric, before length of time, in a medium of a higher latent.--Now this conversion of fluids into or lower temperature than their own, they solids is perpetually going on in the aniwill be found at the end of that period not mal frame, hence, as perpetually will of the same, but of different degrees of latent caloric become disengaged, and so temperature;—and that which is of the become sensible in the system. higher is said to have a less, that which is This theory, which we have endeavoured of the lower temperature, a greater capa- to state as clearly as possible, is, on a city for caloric, for it is evident that to be superficial view, very plausible; but upon raised to a given degree, the former will I a closer examination our credence will require less than the latter --Solids have not be so readily yielded ;- for setting

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corror.........romercroroona aside the difficulty of ascertaining the unceasing combinations and decomposirespective capacities for caloric, of arterial tions of imagination, arise from what may and venous blood concerning which the be termed secondary ideas, or ideas of restatements of eminent men are at utterflection ;-these, though depending upon variance, we obtain no satisfaction as to the powers above named, are connected the differences of temperature which exist | inseparably with the constitution of the between the warm and cold blooded ani- mind, and are necessarily formed in the mals, whose blood' equally undergoes a course of its operations. Without expachange by means of the action of atmos- tiating upon them, (as the line of our plan pheric air,- besides which there are num- merely touches upon the subject,) we shall. berless phenomena, utterly irreconcileable state what we 'consider them to include; with it, so much so, that its supporters 1st, Ideas of Personality or Distinction, seem blinded by its ingenuity, or perhaps —2nd, of Time, 3rd, of Power,—4th, of have neglected to examine it in all its | Truth, 5th, of Duty, 6th, of Deity. relations.

Though this is an inviting field, we shall. The present state of physiological know- not enter its precincts, but return to our ledge is yet too imperfect to allow a com- main subject. plete and satisfactory theory to be given. Now the actions of instinct are evidently To ourselves it appears that the tempera- | unconnected with these intellectual operature of animal bodies depends neither on tions,—they result from no intellectual chemical nor mechanical principles, but process, nor require mind for their perthat it is associated in some mysterious formance ;-for we witness the effects of manner with the vital principle, as exhi. this power in the zoophyte, and worm desbited in the innumerable operations con- titute of brain, as well as in the higher tinually taking place in the organic frame, orders, arising even to man.- We may

those endless combinations and decom- observe also; that instinct presents a feapositions involving perpetual electrical ture the reverse of what is exhibited by changes,-that strange energetic influence any intellectual process leading to action, of the nerves, whose true nature and mode inasmuch as such action is not of necessity, of action is yet veiled in obscurity.

-in other words, the impressions made Having thus far explained the leading upon us by external objects, or the ideas phenomeną of life, in organic sentient of reflection suggested by memory, when beings, resulting from those inherent pro- they are the subjects of our intellectual perties or laws which we have termed powers, do not necessarily lead to any consensibility and contractility, or, according trol over the body, in consequence of an act. to others, irritability, it remains for us to of volition.-Between the impression and notice another law, which we stated to be action, there is always a process of thinkassociated also with organic existence. This ing, of course varying greatly in its nature law is Instinct.

and duration, according to the subject, But in the first place, it will be requisite but still absolutely required to connect that we should clearly explain what we the action with the impression, or idea. mean by this term,--a term very vaguely Now, as it respects instinct, the case is used, and often confounded with reason. very different, here the action is immeInstinct, then, we consider to be a property diate,--there is no process of thinking, of vitality, possessed by the brute and no deliberation, no train of reasoning, man ;--its actions being not the result of influencing volition.--There is required, judgment, or reflection,-not dependent as it were, an effort to carry into effect the upon mind, but arising from a principle action which depends on an intellectual imparted, with certain modifications, by process, while, on the contrary, the actions the divine Author of all things, to the of instinct require no such efforts, they whole series of organic beings, and con- are spontaneous; they follow the impressequently, as far as it goes, it is a principle sions with immediate consent ; – and unerring in its operations,

indeed the impulse cannot be successfully If we examine the constitution of our resisted without a considerable struggle. own minds, we shall find that the powers, Hence the discipline our domestic animals, by which, through the medium of our require, to render them serviceable to our senses, we gain an acquaintance with the wants ;-while in ourselves, obedience to nature of things around us, may be re- the voice of reason and religion, rather solved into three :-viz. Attention, Me- than to the impulse of instinct, creates a - ' mory, and Imagination ;-but from the perpetual warfare. operations of these powers--their com- We trust that our ideas of instinct are. plicated processes, and especially the understood,—there has been much conly

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sion on the subject, which renders a clear / The nearest of the inferior animals, to explanation the more desirable. Reason man, although it must be confessed at an then we would call the exercise of the immense distance and inferiority, is the mental powers, comprehending all their elephant,--and now descending down the inovements ;-Instinct, those active powers chain of beings, and decreasing in every associated with vitality, which impel to the link, reason becomes more and more con. performance of actions (often intricate and fined, till in a few removes from man, or curious,) unconnected with any process of far at least before it has attained the limits reasoning, and independent of habit. Thus of the succession of animals, it has died it is the work of mind, in man, to con | imperceptibly away. struct the simplest habitation, but instinct

W. MARTIN. impels the bee to build the “ sightly hexa Hammersmith. gon," the bird, to frame the nest.

(To be continued.) In our application of the principles thus laid down, we would not be understood as denying that the brute orders. through. ON THE SECURITY OF ROOFS IN LARGE out the whole series, are in any degree

BUILDINGS, gifted with powers of a higher order than 1 MR. EDITOR, instinct ;-On the contrary, however many, SIR,—Half a century, at least, has elapsed who have not duly considered the subject, since it became fashionable to crown very may ridicule the idea, we cannot doubt spacious and lofty rooms with flat ceilings, that numbers evince the possession of without the intervention of columns or thinking powers, and we are sure that side arches, as collateral supports, in order those who have paid attention to the to divide the bearings of the principal habits of animals, will agree with our | beams. Thus the whole weight of the opinion. They are certainly endowed with roof," notwithstanding the trusses which the the powers of attention, and memory, | principals form aloft, rests upon the ends and perhaps also imagination,—they dis of these beams, and presses entirely upon play a knowledge of time, of power, and the walls of the edifice; and, should one of of cause and effect, the results, strictly these ends fail, it might bring down the speaking, of mental operations, and called roof. forth and modified accordingly, by differ- | In large public buildings, such as ent circumstances ;-but in the impulse of churches, chapels, halls, &c. this is coninstinct, no mental operation participates. sidered to be a great modern improvement;

-The brute creation, however, possesses because the eye of the spectator can in these higher powers in a very limited and such rooms rove over a very spacious area inferior degree ;-hence, though the dog without interruption; and the whole conor horse may discover, to a certain extent, gregation or company are thus at once a knowledge of time, or power, and cause introduced to each other and to the and effect, we cannot suppose either of preacher or speaker, and he is at once inthem to possess even the most imperfect | troduced to them. The voice, also, in ideas of truth, (abstractedly considered,) I these rooms is supposed to range more of duty, or Deity.--Man, therefore, stands freely throughout a large area, and to be pre-eminent and alone, a being destined more distinctly heard than in rooms of for immortality; his mind, in grasp gigantic, equal dimensions, where columns or side confines its views not alone upon the pre- arches are reared from the floor to the sent, but with anxiety looks onward to the ceiling. future, and believes, where it cannot com Modern invention has, however, in the prehend; limits its speculations not only to cast iron column, introduced to the this fair world, with all its changes, all its architect a strong and durable support, objects, all its varied beauties, but mounts which, from the smallness of its dimensions, to other spheres, tracks the shining planets neither interrupts the eye nor confuses the in their mazy path, measures their distance, finest tuned voice: and these columns calculates their rapidity, and weighs them, might, during the erection of an edifice, be as it were, in a balance, then passing on- carried up to the underside of each princiward from these glorious works to the pal beam, upon the head of each gallery Power who made them, bows humbly and column, by merely adapting the places of adores. These high endowments are the columns which support the galleries to wisely denied to the brutes ;-though, as the places of the principal beams. Thus we have said, we may often discern the every principal beam of the roof would operations of reason, lowindeed and limited, have four supports, instead of two; and influencing their actions,

| the bearings of these beams would

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