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prove; though we may not in this, as cident so apparently trivial as seeing an in numberless other instances in creation, insect resting on
a flower, to “look be able to point out the precise design through nature, up to nature's God.” intended by Providence in the early blooming of the snow-drop. We have just met with the following
MELANCHOLY EFFECTS OF SUDDEN chance incident, which we conceive may
FRIGHT. throw some light on this subject.
Walking in a garden, during one of the To indulge in the disposition, too prespring-like days, which were so common valent among many, to excite sudden terror during the early part of' 1834, we observed or alarm in the breasts of others, is highly on a snow-drop blossom, a very uncommon criminal. A moment's consideration must insect for this season of the year—a wall- convince us, that what may pass off as a wasp, (odynerus murarius,) one of the harmless jest when practised on one of a solitary species, of a dark glossy black bold spirit, may produce the most disascolour, crossed with narrow bands of a trous consequences when applied to anpale golden yellow. The poor thing ap- other of a timorous disposition or nervous peared to be very sluggish and languid, frame. benumbed, no doubt, by the cold, though Various have been the afflictions of a partially revived by the bright sunshine, permanent nature, brought on the young which was then streaming over the open- and the fearful, by a wanton or thoughtless ing blussoms of clumps of snow-drops attempt to frighten them. Surely many and primroses, planted at intervals in who indulge in this mischievous propenthe borders. We will not assert, that sity, merely through a love of frolic, would this feeble wall-wasp actually found any put a restraint upon themselves if they sip of honey in the snow-drop blossom ; were at all aware of the possibility of enfor though such is very probable, it is tailing an infirmity on a fellow-creature, always hazardous to conjecture without only to be relieved in the final hour, actual observation, respecting the actions when this mortal shall put on immortality. of creatures, which are directed either me- In a new work, published on the disdiately or immediately by Him
eases of the ear, two instances are related worketh by means, and contrary to means," wherein sudden fear produced the most but it led us to believe this conjecture at melancholy effects. The one was that of least plausible.
a child, who, being thoughtlessly frightened And may it not be, (we went on to sup- by an elder sister, was affected with lotal pose,) that the early blowing of the snow
deafness. In the second case the consedrop, as well as the late blowing of the quence was yet more fearful; for the little ivy, and some other plants, is destined to sufferer, terribly alarmed at being put into a spread a table in the wintry wilderness for dark cellar, by a servant, became not only such insects as may, like our poor wall- totally deaf, but totally blind also ! Wasp, have accidentally survived the ge- Think, reader, of the delight afforded by neral destruction of their kindred on the the view of rising and setting suns, of the first setting in of cold weather ; or such varied objects of creation, and of the faces insects as the hive bees which may of our dearest friends! Think of the pleachance to be roused from their torpid sure and profit to be derived from books, sleep, by weather milder than usual, or by especially the book of books, the Bible. an occasional day of sunshine ? Many Think of the delight communicated by soothinsects, in such circumstances, do certainly ing music, the singing of birds, the soft voices perish, as do summer insects by some of affectionate friends, and the cheering coutempests, and as cities are destroyed by solations of the promises of eternal life, earthquakes ; but it is at least pleasing breathed forth with heartfelt energy, by the to reflect, that the snow-drop, and a few ministers of the gospel of peace; and then other flowers of its companionship, may ask yourself, if the poor gratification of a be serviceable to prevent a few es, wasps, momentary pleasure, would recompense and similar insects from perishing of abso- you for the stinging remorse your heart lute famine. Such a reflection, indeed, would feel in the bitter consciousness of to our mind, throws a brighter interest having deprived a human being of these around the snow-drop, than all the poetry advantages for ever. chat was ever written in its praise; and Another melancholy instance of the sad we think it will do so to the minds of all effects of sudden fright, is that of a schoolthose who are accustomed even in an in- boy, who was lifted up in bed, in the dark,
ON THE HEART AND CIRCULATION OF | right ventricle, it effectually prevents a drop THE BLOOD.NO. II.
from returning upon the contraction of the ventricle; a circumstance of material importance, and beautifully provided for. The right ventricle, as we have said, is destined to receive the blood from its corresponding auricle, and transmit it to the lungs, in order that it may be subjected 10 the action of the atmospheric air, taken in at each inspiration, or during breathing.
Now, the vessel arising from this ventricle is an artery, termed the pulmonary, at the root of which, internally, are situated three valves, (the semilunar valves, from their shape,) which allow the blood to pass during each contraction of the ventricle, but prevent its falling back, during the intervals of the contractions, as it would do, but for this exquisite piece of mechanism
The nature of the valves may be easily imagined from the following sketch, which presents them first in their natural situation, a section of the artery being made just
The above is a sketch of the right auricle and right ventricle laid open; showing g. the corneæ columnæ with their tendinous chords; k. the tricuspid valve; e. the obliterated foramen ovale,(open before birth, but closed afterwards,) which communicated between the two auricles. The right auricle of the heart is the im
Sacred mediate receptacle for the blood, which,
to hold be having accomplished its course, is returned above them, and then as they appear when back to that organ, in order to be first sent the artery is slit up longitudinally, and to the lungs, whence it returns again to the laid extended. heart, and is then sent out afresh on its journey through the system. Into this right auricle, the blood is brought by certain veins, 'vene cavæ, 0.q. page 84,) which terminate in it; and its thin walls are strengthened by bundles of muscular fibres, disposed on its inner surface, and termed musculi pectinati, from their resemblance to the teeth of a comb. The division-wall between The blood is returned from the lungs to the two aurieles is termed the septum au- the left auricle of the heart, by four pulricularum. The right auricle communi-monary veins. The coats of this auricle cates with the right ventricle below, by are somewhat firmer and thicker than those means of an opening termed ostium veno- of the right, which in other respects it sum, at the edges of which, within the closely resembles. The opening of the ventricle, is situated a valvular apparatus, left auricle into the left ventricle, is also consisting of thin, firm membrane, divided furnished with a valvular membrane, but into three parts, and called the tricuspid only divided into two parts, and called, valve, from a slight resemblance to three from its resemblance to a mitre, valvula spear heads. To the edges of this valvular mitralis. The cut on page 93, shows the left apparatus small muscles (carneæ columna) auricle and ventricle, laid open. are attached by tendinous cords,(chordæ ten- The blood received by the left auricle dine@)which prevent the membrane from be- from the lungs, is transmitted through ing forced into the auricle. Thus, though the the opening into the left ventricle, which, tricuspid valve readily admits the passage of as it needs the greatest portion of strength, the blood from the right auricle into the is characterized by the superior thickness and fleshiness of its walls. It is from this to build up the animal machine, to mainfount of life, that the blood is propelled tain vital warmth and energy, to the end throughout every part of the system, that every function may be duly performed, serving to repair the losses of every organ, and the body live.
The great artery which arises from the new characters which render it subservient left ventricle, the ramifications of which to the vital operations of the body; its (under various names, for the sake of colour, which was dark, is now altered, and convenience and precision) are distributed becomes bright florid red, or nearly scarlet. universally, is the aorta. It is thick and From the lungs it repasses to the heart, by firm, and, like the pulmonary artery, is pro- means of veins, into which the extreme vided with three semilunar valves.
ramifications of the pulmonary artery graAll the cavities of the heart are lined dually merge. These veins, named also pubwith a fine smooth membrane, or coat, and monary, terminate in the left auricle of the externally the whole organ is closely enve- heart, which, receiving the blood, contracts loped in a similar membrane, which is a and transmits it to the left ventricle, and reflection of the internal lamina of the pe- this propels it through the aorta, to every ricardium. The pericardium is a mem. part of the body, where it gradually loses branous bag which contains the heart, but its peculiar arterial properties, which seem is not adherent to its sides. There is ge- as it were to be expended upon the system, nerally found in it a small quantity of and is again taken up by the veins, into serous fluid, which is doubtless of use in which the extreme ramifications of the arlubricating the surface of the heart. teries insensibly merge, to be conveyed to
The course of the blood may be thus the right auricle, and again go through the summarily described : passing from all
process as described. parts of the body, by means of the veins Thus, then, the right side of the heart is to the heart, it is received by the right always filled with dark-coloured or venous auricle, into which the vena cava is per- blood ; the left side with bright or arterial petually pouring it; the right auricle con- blood : the arteries carry the blood from tracting, propels it through the pulmonary the heart, the veins bring it back ; the arartery to the lungs. Now this artery rami- teries of the system are filled with brighi fies most minutely over the thin tissue of blood, the veins of the system with dark; which the cells of the lungs are composed, while, on the contrary, the pulmonary artery (for the lungs are composed of multitudes takes blood of a venous character to the of cells, into which the air enters in the lungs, and the pulmonary veins bring back action of breathing,) and there acquires blood of an arterial character to the heart.