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with agility. The general colour is a dull | blade, and the other one in the side. The brownish grey; a white abrupt line passes riders fortunately escaped unhurt, but from above each eye over the face, and came home with very woful countenantwo white spots occupy the cheeks; a thin The koodoo is equally resolute. mane begins between the horns, and runs
M. down the back; on the neck it is brown, but on the back, where it is shorter, it is from this white dorsal line pró
ON THE HEART, AND CIRCULATION OF
THE BLOOD. —NO. V. ceed eight transverse lines of a similar colour on each side, beautifully striping the The arteries of the system, as we have body. Under the chin a long pendent observed, are the tubes through which mane commences, and extends to the the blood is conveyed from the heart chest. The ears are large; the tail long, to every part of the frame; it is returned tipped with blackish brown, but white on to the heart by the veins. The veins the under surface.
are tubes, composed, like the arteries, of In its general manners, the koodoo re-three coats, but so thin and transparent sembles the rest of the larger antelopes. that it is difficult to separate them. The It is found in small herds in the Karroo, commencement of these vessels is very but its favourite localities are glens be- obscure, owing to their minuteness, and tween the hills and mountains, where the impossibility of drawing a line between both food and water are abundant, and the artery and vein in a network of capilwhere a tall growth of underwood affords laries. As they proceed, they become more it shelter. When surprised by the hunter, and more distinct, till at length they form its first effort is to dash through the large tubes, capable of being singularly dithicket; in doing which, it lowers its neck, lated, owing to the elasticity of their texand at the same time projects the head ture. One point in their construction is horizontally so as to lay the horns on very curious and interesting; we allude to each side of the shoulders, in order that the valves with which they are plentifully they may assist in clearing a passage, and furnished. These valves in the veins traat the same time protect the fore-quarters velling up to the heart from the lower parts from the bruises to which they would of the body, are so contrived as to let the otherwise be liable. When hard pressed, blood pass freely, but prevent the columns the koodoo, like the oryx, makes a vigo- of Auid from returning or pressing with any rous defence, striking desperate blows great force on the minuter veins and capilfrom side to side with his horns, against laries; the superincumbent weight being the dogs who keep him at bay, and some- broken by each valve. In the veins retimes even rushing upon the hunter. In- turning from the upper parts of the body, deed, at certain seasons, the male koodoo the valves do not, indeed, support the cois very furious, and will not hesitate to lumns of blood, a circumstance here not commence the assault; in general, how- needed, but they prevent its return backever, it trusts to its speed for safety. wards towards the capillaries or venous
In its native wilds, the koodoo has radicles, as we have noticed in the veins of other enemies besides man. It is the the lower parts. prey of the lion; hence it is habitually The course of the blood, then, is effected, wary, while, as an additional security, its in the first place, by the force of the heart, senses of hearing and smell are extremely aided by the contractile power of the acute; nor when attacked does it fall an arteries, till it arrives in the veins ; where, unresisting victim to the tyrant of the in the second place, it appears to be wilderness. The koodoo is frequently pelled by several combined causes.
The alluded to by Burchell in his travels, who dilatation of the auricle, for instance, progives a sketch of the skull and horns. In . duces a vacuum, into which the blood of page 313, vol. i., he states, that on one the vena cava naturally rushes, the space it occasion his hunters, who had been out occupied being immediately filled up, the to shoot the kanna, an allied species, paid general column rising in a relative propordearly for two which they had killed, " by tion, as regularly as the vacuum is made. their venturous imprudence in riding into But the progressive motion of the blood the midst of a large herd; when the animals through the smaller veins appears to be in their own defence turned upon them, materially accelerated by muscular exerand gored two of the horses, one of which tion. received a deep thrust under the shoulder- We know how great a sense of weight and
prolistlessness is felt, after remaining for some | thoracic duct does not, however, only retime in one position, without exerting the ceive the lacteals ; for the absorbent vessels action of the muscles. This feeling would of the skin, as well as of every part of the seem to arise from the sluggishness of the frame, here also terminate, so that whatever circulation, and the accumulation of blood they take up, or remove, goes through the in the venous system at large, which re- above process. How wonderful, how mysquires an impetus from muscular activity, rious, how little understood, are our own in order to its due circulation.
bodies, which are fearfully and wonderfully But it may be asked, is not the blood made! Our life, moment by moment, dewasted by the various secretions which are pends on the nice and delicate adjustment elaborated at its expense ? It is; and its and action of a thousand minute parts or stores are at the same time as regularly re- organs, of which multitudes have never even plenished. The nutritious particles of the heard ; the slightest flaw deranges the mefood we eat, become blood, by a process chanism of the animal machine, and death which baffles the researches of the chemist, ensues ; yet there are men who see nothing and shows us how little we know of life of beauty, nothing of glory, nothing of Aland organization.
mighty power, in the workmanship of these The office of the digestive organs is to vital tenements, the temple of a never-dying convert food into chyle; to speak more de- soul. us, while we contemplate the finitely, we may state the progress as fol- subject, bow with heartfelt adoration before lows:- When the food is received into the our Lord and Maker. stomach, it becomes mixed with the sali- Into the nature of animal temperature, or vary and gastric fluids, and by their agency the laws of vital heat, (which, while it apis dissolved into an uniform pulpy mass, pears to be connected intimately with the termed chyme; this is its first change: it circulation, is also no less so with the energy now passes into a portion of the alimentary of the nerves,) we shall not attempt to encanal, termed the duodenum, and there ter. No theory as yet laid down is at all becomes mixed with the pancreatic juice satisfactory; it appears to depend neither on and the bile, and by the action of these chemical nor on mechanical principles, as fluids a complete conversion is effected on some have imagined, but to be associated in that portion fitted for the purposes of the some mysterious manner with the principle animal economy, which is termed chyle. of vitality; a principle exhibited in the This chyle is immediately taken up by innumerable operations continually taking multitudes of minute tubes which proceed place in the organic frame, in those endless from the inner surface of the alimentary combinations and decompositions involving canal, and are termed lacteals. If we ex- perpetual electrical changes, and that strange amine these tubes in an animal recently energetic influence of the nerves, whose killed, and before the vital warmth is ex- true nature and mode of action are veiled in tinguished, we shall see them (at least if obscurity. the animal has been recently fed) filled with While we thus regard the structure and a milky fluid, whence their name of lac-operations of our mortal fabric, let it be to teals : this fluid is the chyle. The lacteals us a theme of profit and instruction, rehaving thus absorbed this nutritive prepa- membering that the appointed time cometh, ration of the food, after communicating when the silver cord shall be loosed, “ the freely with each other, pass through certain golden bowl broken, the pitcher broken at glands, termed the mesenteric, where the the fountain, the wheel broken at the cistern, chyle appears to acquire new properties. the dust returning to the earth as it was, and Emerging from these glands, the lacteals the spirit to God who gave it." M. carry the chyle onwards till they enter at last into the thoracic duct, a vessel which
SCRIPTURE REFERENCES TO THE passes up along the spine, and pours the chyle into the left subclavian vein, just where it becomes united to the vena cava ; The Hebrews look upon the heart as the here it mingles with the blood. It has not, source of wit, understanding, love, grief, however, yet fully acquired the ultimate and pleasure. Hence are derived many change : received with the venous blood by ways of speaking. An honest and good the heart, it is thence sent through the heart; that is, a heart studious of holiness, lungs and again returned to the heart, in- being prepared by the Spirit of God to corporated with the rest of the vital Áuid, entertain the word with due affections, disof which it now forms a part in every sense, positions, and resolutions, Luke viii. 15. to be sent out to nourish the system. The 'We read of a broken heart, a clean heart,
an evil heart, a hardened heart, a liberal | the whale's belly ; so shall the Son of heart; a heart that does an act of kindness man be three days and three nights in the freely, voluntarily, with generosity. To heart of the earth,” in the grave, Matt, xii. incline the heart to God; to beseech him 40. to change our stony hearts into hearts of flesh; to love with all one's heart, &c. To turn the heart of the fathers the chil
HOSPITALITY OF THE ANCIENT ARABS. dren, and the heart of the children to their The virtue of hospitality often degenefathers, Mal. iv. 6; that is, to cause them rated into foolish extravagance; and there to be perfectly reconciled, and that they were individuals who strove to outdo each should be of the same mind. “ Let no other in deeds of romantic generosity. man's heart fail;" let no man be discou- Those who excelled in the magnificence of raged, 1 Sam. xvii. 32.
their bounty, were crowned with wreaths, To want heart, sometimes denotes to as if they had conquered at the head of an want understanding and prudence, Hos. vii. army. The liberality of Halim was pro11. “Ephraiın is like a silly dove without verbial, and has immortalized the tribe of heart; they call to Egypt, they go to As- Tai. The suppliant he never dismissed syria.” They have no judgment or under- from his tent unrelieved. Often were forty standing of the right way, to free them- camels roasted at a single feast; and, in a selves from their troubles, which is seen in season of extreme scarcity, he killed the their seeking to Egypt and Assyria. "O only horse he possessed, so valuable, that fools, and slow of heart," ignorant men,
,with- the Roman emperor had sent an embassy out insight and understanding, Luke xxiv. on purpose to procure it. Hatim's bene25. “This people's heart is waxed gross volence was hereditary; his father rejoiced
- lest they should understand with their when he had emptied his folds to feed the heart,” Matt. xiii. 15. Their heart is stu- hungry, and his mother was interdicted from pified, so as to be destitute of understand giving alms for a whole year, lest her proing; they resist the light, and reject all im- digality should reduce the family to beggary. pressions of truth. “ The prophets pro- He himself was so inconsiderate as to distriphesy out of their own hearts,” Ezek. xiii. bute the greater part of his flocks among a 2. They prophesy according to their own troop of needy poets on their way to thecourt inclinations and affections, and what their of Hira. His beneficence was as unwearied own imaginations suggest to them, without as it was extensive. On the longest and any warrant from God.
darkest nights, he would leave his bed, if To lay any thing to heart, is to set one's some hapless pilgrim required shelter; and, heart on any thing; that is, to remember it, wrapt in his cloak, procure with his own to apply one's self to it, to have it at heart. hands a light from some neighbouring “No man layeth it to heart;” no one con- tent. Not satisfied with kindling his “ fires cerns himself about it, Jer. xii, 11. on the mountains,” he would send forth his
The heart dilates with joy, contracts with dog ; that, by its barking, strangers might sadness, breaks with sorrow, it resists truth; know where to find a place of rest. His grows fat and hardens in prosperity; God memory was revered over all Arabia ; and opens it, prepares and turns it as he pleases. a female captive, taken in battle, regained To steal one's heart, is an expression in Gen. her liberty, when she pronounced herself xxxi. 20, margin, “ Jacob stole away the to be the daughter of Hatim Tai. heart of Laban;" that is, he went away without his knowledge and consent. The heart melts under discouragement; the heart for
THE PENDULUM.-No. II. sakes one under terror; the heart is desolate in amazement; the heart is fluctuating in The increase or decrease of temperature doubt. To speak to the heart, means to has a considerable influence on the oscillacomfort, to say pleasing and affecting things tions of a pendulum. A bar of metal which to any one.
when cold will pass easily between two By the heart likewise, the middle of any uprights, will not do so when heated redthing is meant : Tyre is in the heart of the hot, for heat expands solid metallic bodies. seas, in the midst of the seas, Ezek, xxvii. For this reason, a pendulum which beats 4, margin, “ We will not fear, though seconds in a low temperature, would the mountains be carried into the heart or cease to do so if taken into a hotter midst of the sea,” Psalm xlvi. 2. “ As climate, for its length would be increased. Jonas was three days and three nights in This is a fact of great importancein horology, and mechanics have invented various me- we suppose a, b, to be raised as much as thods of compensating for this alteration in c, d, is lowered, the distance of a, b, from the length of the pendulum ; sometimes by making the rod of the pendulum of a substance that would not expand appreciably by heat, and sometimes by contrivances that correct the increase of length that results from a change of temperature. The length of a rod of dry wood is not altered by a change of temperature, and it would be the best possible contrivance, if it could be perfectly protected from the hygrometric action of the air. It is, however, in a considerable degree defended from moisture, when rubbed over with bee's wax, and makes the most accurate pendulum of this sort, when thus prepared.
The two best compensation pendulums, are the mercurial and the gridiron. The mercurial pendulum consists of a rod of brass, or other metal, to the end of which a cylindrical vessel containing mercury is attached instead of a ball. The same increase or decrease of temperature that affects the pendulum rod has an influence upon the mercury in the vessel, and the s will remain unchanged. But the increase one corrects the other. If the rod suffers of temperature which expands the other expansion, the centre of oscillation will parts of the instrument, expands the rod rise; but if the mercury be duly pro- T, L, and therefore the distance between G portioned, its expansion will be such, that and t are proportional. Now, looking at the distance of oscillation from the point of the instrument generally, we observe that suspension will be always the same, and S F, A Ć, TL, when expanded by increase of therefore, whatever may be the variation of temperature, tend to increase the distance temperature, the pendulum will beat se- between s and G, that is, the point of susconds.
pension and the bob. To prevent this, we The gridiron pendulum was invented by must make the frame c, a, b, d, of such a Mr. John Harrison, and is a very ingenious a metal that its expansion upwards may and useful instrument. It is well known, exactly neutralize the combined downward that the different metals and metallic alloys, expansions, and thus the distance between expand variably under the influence of the s and a will be preserved. same change of temperature. It is therefore The great use of the pendulum is in its evident, that bars of different metals may application to clocks, but when we speak be so arranged as to correct each other's of pendulums being adapted clocks for expansion when used in the construction of the purpose of measuring time, it must pendulums.
not be supposed that they are the moving Let G be the bob of a pendulum, and s power, for they merely act as regulators, the point of suspension : A, B, C, D, is a and the motion originates in the fall steel frame, to which is attached the rod of a heavy weight, or in the recoil of S, F; and a, b, c, d, is a frame of some a spring attached to the machine. Weights other metal, and is attached to the rod C,D, are invariably used for clocks, springs in at the points c, d. At t the rod T, L, is watches; but the latter are generally resuspended, passing freely through the hole gulated by a balance-wheel, and not by
Now if the temperature be raised, à pendulum. The contrivance by which the frame A, B, C, D, will dilate downwards, the pendulum of a clock is connected that is, C, D, will be carried further from with the train of wheels, and regulates the point s; and if the mass of the their motion, is called the escapement; and pendulum be thus brought downwards, it of this we have several varieties, as the will no longer beat seconds. But the lever, and the dead-beat escapement, the frame c, a, b, d, is also expanded, and the last being so named on account of its very expansion is upwards, so that while c, d, peculiar sound. is lowered, a, b, will be raised. Now, if We have hitherto spoken of pendulums
At a proper
as vibrating in the arc of a circle, but themselves. Let them live in separate there is a mathematical curve called a towns; let them have a “ Tadmor in the cycloid, and if the bob of a pendulum Wilderness,” if they will. could be made to vibrate in it, its oscilla- distance from all sober towns, let a tions would all be performed in equal DRUNKEN TOWN be established. Let them times, whatever the length of the arc. be a distinct community, as far as may The cycloid is that curve which is formed be. I was amusing myself with imaginby the revolution of any point on the cir- ing such a society — all drunkards. I cumference of a circle, the circle itself thought a goodly town was built for them, being made to revolve on a plane. There with every convenience that art could are some very remarkable principles which wish, walled round, as was fitting, (for might be mentioned in reference to this drunkards are poor desenceless things)
Of all paths not in a straight line, with just one sober man to lock the gate, the cycloid is that in which a body can and to keep out sober intruders. I thought pass the most readily from one point to they were all “settled” at last, and gone another. The right line is, of course, the to bed as “comfortable” as they could shortest path between two bodies, and if a wish, each having a good "night cap,” man in a balloon would throw a stone to and I watched to see how they came on some point on the earth in the shortest next morning. The first that rose was path, he would cause it to take the direc- a gentleman,” of course, that had taken tion of a right line ; but if he wished to up his night's rest upon a dung heap,throw the stone in the line of shortest what is called in Yorkshire a “muck descent, it must be made to move in the midding,” and a very decent dormitory cycloidal curve, for it would not only reach for a drunkard. He went to knock up its destination sooner, but would strike the the priest of a gin temple, which was no object with greater energy. The study of
This done, he demanded the mathematics has taught man this truth, “a morning,” if you know what that is, of · and instinct has taught the falcons to fly the best sort; but it now turned out that in the cycloidal curve ; and it is in conse- the lady of the house having had “a drop quence of their flying in a cycloid when too much,” had left the tap running, and attacking their prey, that they possess so it was all gone! And now the cellar; great a velocity, and strike with so great a but here again was bad luck, for the key force.
was lost! Misfortunes seldom come singly; Ingenious mechanics have attempted, for for the “gentleman” who applied for his the reasons already stated, to cause the “ morning," had no sooner begun to pendulum to vibrate in this curve; but smack his livid lips, after tasting it, than hitherto with little success; for so few of he discovered that his purse was lost. It the practical difficulties have been removed, appeared that this was to be market day; that it is not probable that this desirable but, alas! where was the market? Butchers object will ever be accomplished.
had been so busy “enjoying themselves,” that the carcases were undressed. Drovers were detained on the road after taking “ a little drop too much.”. The bakers
had, in pursuit of “good fellowship,” forI have heard strong objections to any gotten their bread batches. The carrier, interference with the habits of society; whom the grocers had sent to the neighand it has been said, that it infringes bouring sea-port for supplies of tea, sugar, upon the rights of individuals to prescribe and gin, was “ at a lock,” in consequence sobriety to them, and to put them to any of “a little conviviality" he had indulged inconvenience, because they choose to in. The miller, the honest miller, appeared get drunk. Much fault has been found by as if someone had thrown dust in his some, with an opinion which I have ex. eyes, for he had left the mill-dam gates pressed, that drunkenness ought to be open, and the water was gone. Crispin, punished. One person told me I was the shoemaker, “to oblige his customers, • strait-laced”—what he meant is for him had just spent a few evenings “in a free to say. If he means I am a bigot and a way,” till the lap-stone was mouldy, and “coercion” man, I will promise to amend, his worthy neighbours were barefoot. The and to take his side of “non-interference” tailor and his goose had quarrelled; he upon one condition, and that is, that had only been a few days at the sign of drunkards shall form a community for “the last shift,” “to drive dull care away."
A COMMUNITY OF DRUNKARDS.