페이지 이미지
PDF
ePub

In old age, and in adults with stiff and ossified cartilages, the lower end of the sternum advances, and the ribs move outwards. As both the superior thoracic and the diaphragmatic muscular actions are always, and the movements usually exaggerated, the head is lowest at each inspiration, indicating excess of costal (query, spinal 1) motion; while the larynx descends considerably, indicating excess of diaphragmatic action. The rythm of respiration is materially and characteristically affected in Emphysema and Bronchitis. The inspiration is short; the expiration is prolonged. During expiration the air rushes out easily and quickly at first, but with increasing slowness and difficulty towards the end; and this increasing slowness of expiration distinguishes the obstruction of the smaller bronchi from obstruction in the larynx, in which, latter case it is also prolonged, but is equally slow throughout. Pleuritis usually restrains the respiratory movements, sometimes because of pain, but sometimes although there be no pain. In some cases the movements are not all lessened, and, in simple or dry pleuritis, they are seldom, if ever, entirely destroyed. The respiratory movements of the opposite lung and of the unaffected portions of the same lung are from compensation exaggerated. We pass on to make some extracts from the summary of the effects of phthisis on the movements of respiration:

* There is almost invariably some movement of inspiration over a cavity. But

although the part in question always advances during inspiration, especially a deep "inspiration, yet at the beginning of inspiration it sometimes recedes slightly, and

frequently stands still just before its inspiratory advance.

“The firm walls surrounding a cavity have no inspiratory expansion; the respiratory movements over the region of dullness surrounding a cavity are much smaller than those over the cavity itself; they are often immobile ; their motion is often reversed at the beginning or through the whole course of inspiration and expiration.

“The descent of the diaphragm is somewhat restrained on the affected side in about one half of the cases If the diaphragm act freely, the movements of the sixth costal artilage may be reversed The respiratory movements of the oppositelung is, in the great majority of cases, exaggerated.” (pp. 455-6.)

In the fourth part, the Effects of Diseases of the Heart and Pericardium on the Movemments of Respiration are considered. In severe cases of pericarditis with effusion, in which the central border of the diaphragm is inflamed, the motion of the abdomen at the Centre may be diminished, absent, or, reversed during inspiration, and the movements of the left fourth, fifth, and six cartilages may be reversed (either wholly, or only at first), abolished, or diminished. When the heart is materially enlarged, the expansicn of the lower end of the sternum of the cartilages and ribs in front, and to the side of the cardiac region, is restrained. If there be pericardial adhesions, with valvular disease aud enlargement of the heart, the costal expansion in front of the heart is restrained. Moreover, while the movements of the centre of the chest and abdomen are restrained, the lateral superior movements of the former, and the lateral movements of the latter are not restrained; the extent of the im. pulse, too, is not lessened during inspiration. The author has given, near the end of his paper a list of the several modifications which respiration may undergo, arranging under each variety 7–iv. 5*

of deviation from the healthy movements, the diseases which give rise to that particular abnormal condition. He admits that we cannot form a diagnosis of disease, by observing the arrest, restraint, or exaggeration of any particular respiratory movement; but contends that we may thereby make a good step towards it, inasmuch as we narrow our inquiry to a certain small class, and make out the seat of the disease by our inquiry.

Extensive tables are appended, in which are recorded the results of two hundred different cases observed in health, or under various diseases, on which are founded the conclusions set forth in the paper.

It will be manifest from the copious abridgment we have made, that many of the facts detailed are not new to medical men; still we conceive that, even with regard to these, Mr. Sibson's researches have given increased certainty and precision to our knowledge; while he has pointed out some cases of disease, which his method of measurement is calculated to elucidate, and to which it had not previously been generally applied.

The care and industry with which his memoir has been prepared, reflect great credit upon its author; and we must ever rank among the benefactors of the art of medicine, one who has done so much to facilitate the practical diagnosis of disease.

ART. III.

1. KosMos. Entwurf einer physician Weltbeschreibung Won Alexander von Humboldt—Stuttgard u. Tubigan. 8vo. Erster Band, 1845, pp. 510; Zweiter Band, 1847, pp. 544.

2. Cosmos. A sketch of a physical Description of the Universe. By Alexander voN HuMBoldt. Translated from the German by E. C. Otte.—London, 1848-9. In Two Volumes, post 8vo, pp. 366.

3. Briefe über Alexander von Humboldt's Kosmos. Ein Commentator zu diesem Werke firge bildete Laien. Erster Theil. Bearbeitet von BERNARD Cotta, Professor. Leipzig, 1848. 8vo, pp. 826.

Letters on the Cosmos. Being a Popular Commentary on that Work. By Professor Cotta. First Part.

4. Kosmos für Schulen und Laien nach Alexander von Humboldt. Von Dr. K. G. Reuschle, Professor der Mathematik und Geographie zu Stuttgart.—Stuttgart, 1848. 8vo. Erster Theil, pp. 212; Zweiter Theil, pp. 304.

Cosmos for Schools and General Readers. By Professor Reuschle.

No one can rise from the perusal of the CosMos without the conviction that he has read a most extraordinary work—a work equally remarkable for the profundity of its knowledge in the most varied departments of science, its rich stores of literary research, and the captivating style in which it is written.

The Cosmos, when completed, will form three volumes, of which two only are yet published; and we fear that the advanced age and recent indisposition of its illustrious author render it far from certain when the third volume will appear, or whether it will appear at all. The first volume comprises a sketch of all that is at present known regarding the physical phenomena of the universe; the second is divisible into two distinct and separate parts, the first of which treats of the incitements to the study of Nature afforded by descriptive poetry, landscape painting, and the cultivation of exotic plants; while the second and larger part enters into the consideration of the different epochs in the progress of discovery and of the corresponding stages of advance in human civilization. The third and last portion of the work “will, for the better elucidation of the general picture of nature, set forth those results of observation on which the present condition of scientific opinions is principally based,” and will thus, probably, fill up several apparent blanks in the volumes already published. Alexander von Humboldt was born on the 14th of September, 1769; and is therefore now in his 80th year. None of our readers can be altogether ignorant of his extensive researches in the physical geography of the New World, carried on between the years 1799 and 1804, or of the results of his scientific journey to Siberia in the year 1828, in company with his distinguished friends, Ehrenberg and Gustav Rose, and under the special protection of the Russian government. We merely allude to these points because he refers to them in his preface, in which he beautifully and feelingly explains the reasons that have induced him to undertake the present work, and sets forth, with truth and simplicity, his peculiar qualifications for such a task. “In the late evening of an active life, I offer to the public a work, whose undefined image has floated before my mind for almost half a century. I have frequently looked upon its completion as impracticable, but as often as I have been disposed to relinquish the undertaking, I have again—although, perhaps, imprudently—resumed the task.” The idea of a physical description of the universe, such as he had conceived and resolved to work out, does indeed present startling difficulties; but if any man be qualified to meet and successfully grapple with those difficulties, Alexander von Humboldt is that man.

“A'though the outward relations of life, and an irresistible impulse towards knowled e of various kinds, have led me to occupy myself for many years—and apparently exclusively—with separate branches of science, as, for instance, with descriptive botany, geognosy, ch'inistry, astronomical determinations of position, and terrestrial magnetism, in order that I might the better prepare myself for the extensive travels in which I was desirous of engaging, the actual object of my studies has nevertheless been of a higher character. #. principal impulse by which I was directed, was the earnest endeavour to comprehend the phenomena of physical objects in their general connexion, and to represent nature as one great whole, moved and animated by internal forces. My intercourse with highly-gifted men early led me to discover that, without an earnest striving to attain to a knowledge of special branches of study, all attempts to give a grand and general view of the universe would be nothing more than a vain illusion. These special departments in the great domain of natural science are, moreover, capable of being reciprocally fructified by means of the appropriative forces by which they are endowed. Descriptive botany, no longer confined to the narrow circle of the determination of genera and species, leads the observer who traverses distant lands and lofty mountains to the study of the geographical distribution of plants over the earth's surface, according to distance from the equator and vertical elevation ahove the sea. It is further necessary to investigate the laws which regulate the differences of temperature and climate, and the meteorological processes of the atmosphere, before we can hope to explain the involved causes of vegetable distribution ; and it is thus that the observer who earnestly pursues the path of knowledge is led from one class of phenomena to another, by means of the mutual dependence and connexion existing between them. “I have enjoyed an advantage which few scientific travellers have shared to an equal extent, viz. that of having seen not only litoral districts, such as are alone visited by the majority of those who take part in voyages of circumnavigation, but also those portions of the interior of two vast continents which present the most striking contrasts, manifested in the Alpine tropical landscapes of South America, and the dreary wastes of the steppes in North Asia. Travels, undertaken in districts such as these, could not fail to encourage the natural tendency of my mind towards a generalization of views, and to encourage me to attempt, in a special work, to treat of the knowledge which we at present possess, regarding the sidereal and terrestrial phenomena of the Cosmos in their empirical relations. The hitherto undefined idea of a physical geography has thus, by an extended and perhaps too boldly imagined a plan, been comprehended under the idea of a physical description of the universe, embracing all created things in the regions of space and in the earth. “The very abundance of the materials which are presented to the mind for arrangement and definition, necessarily imparts no inconsiderable difficulties in the choice of the form under which such a work must be presented, if it would aspire to the honour of being regarded as a literary composition. Descriptions of nature ought not to be deficient in a tone of life-like truthfulness, whilst the mere enumeration of a series of general results is productive of a no less wearying impression than the elaborate accumulation of the individual data of observation. I scarcely venture to hope that I have succeeded in satisfying these various requirements of composition, or that I have myself avoided the shoals and breakers which I have known how to indicate to others.” (pp. ix.-xi.)

The first volume commences with an Introduction, extending over sixty-one pages of the English translation. This Introduction consists of two distinct initiatory essays: the first is entitled “Reflexions on the different degrees of enjoyment presented to us by the aspect of Nature, and the study of her laws,” while the second treats of the “Limits and method of exposition of the physical description of the universe.”

Of these essays we have not very much to say. There is an indefiniteness and want of methodical arrangement in them, which we do not find in any other part of the work. Nevertheless, they are beautiful—in many parts, exquisitely beautiful. Who, for instance, can read the following passage without a deep feeling of its intense truthfulness, and of the singular accuracy with which the author can depict human emotions !

“In reflecting upon the different degrees of enjoyment presented to us in the contemplation of nature, we find that the first place must be assigned to a sensation, which is wholly independent of an intimate acquaintance with the physical phenomena presented to our view, or of the peculiar character of the region surrounding us. . In the uniform plain bounded only by a distant horizon, where the lowly heather, the cistus, or waving grasses, deck the soil ; on the ocean shore, where the waves, softly rippling over the beach, leave a track, green with the weeds of the sea ; everywhere, the mind is penetrated by the same sense of the grandeur and vast expanse of nature, revealing to the soul, by a mysterious inspiration, the existence of laws that regulate the forces of the universe. Mere communion with nature, mere contact with a free air, exercise a soothing yet strengthening influence on the wearied spirit, calm the storm of passion, and soften the heart when shaken by sorrow to its in most depths. Everywhere, in every region of the globe, in every stage of intellectual culture, the same sources of enjoyment are alike vouchsafed to man. The earnest and solemn thoughts awaked by a communion with nature intuitively arise from a presentiment of the order and harmony pervading the whole universe, and from the contrast we draw between the narrow limits of our own existence and the image of infinity revealed on every side, whether we look upwards to the starry vault of heaven, scan the far stretching plain before us, or seek to trace the dim horizon across the vast expanse of ocean. “The contemplation of the individual characteristics of the landscape, and of the conformation of the land in any definite region of the earth gives rise to a different source of enjoyment, awakening impressions that are more vivid, better defined, and more congenial to certain phases of the mind, than those of which we have already spoken. At one time the heart is stirred by a sense of the grandeur of the face of nature, by the strife of the elements, or, as in Northern Asia, by the aspect of the dreary barrenness of the far stretching steppes; at another time, softer emotions are excited by the contemplation of rich harvests wrested by the hand of man from the wild fertility of nature, or by the sight of human habitations raised beside some wild and foaming torrent. Here I regard less the degree of intensity, than the difference existing in the various sensations that derive their charm and permanence from the peculiar character of the scene. “If I might be allowed to abandon myself to the recollections of my own distant travels, I would instance, among the most striking scenes of nature, the calm sublimity of a tropical night, when the stars, not sparkling, as in our northern skies, shed their soft and planetary light over the gently-heaving ocean –or I would recall the deep valleys of the Cordilleras, where the tall and slender palms pierce the leafy veil around them, and waving on high their feathery and arrow-like branches, form, as it were, “a forest above a forest;” or it would describe the summit of the Peak of Teneriffe, when a horizontal layer of clouds, dazzling in whiteness, has separated the cone of cinders from the plain below, and suddenly the ascending current pierces the cloudy veil so that the eye of the traveller may range over the brink of the crater, along the vine-clad slopes of Orotrava to the orange-gardens and banana groves that skirt the shore. In scenes like these, it is not the peaceful charm uniformly spread over the face of nature that moves the heart but rather the peculiar physiognomy and the conformation of the land, the features of the landscape, the ever-varying outline of the clouds, and their blending with the horizon of the sea, whether it lies spread before us like a smooth and shining mirror or is dimly seen through the morning mist. All that the senses can but imperfectly comprehend, all that is most awful in such romantic scenes of nature, may become a source of enjoyment to man, by opening a wide field to the creative powers of his imagination. Impressions change with the varying movements of mind, and we are led by a happy illusion to believe that we receive from the external world that with which we have ourselves invested it. “When far from our native country after a long voyage, we tread for the first time the soil of a tropical land, we experience a certain feeling of surprise and gratification in recognizing, in the rocks that surround us, the same inclined schistose strata, and the same columnar basalt covered with cellular amygdaloids, that we had left in Europe; and whose identity of character, in latitudes so widely different, reminds us, that the solidification of the earth's crust is altogether independent of climatic influences. But these rocky masses of schist and of basalt are covered with vegetation of a character with which we are unacquainted, and of a physiognomy wholly unknown to us; and it is then, amid the colossal and majestic forms of an exotic flora, that we feel how wonderfully the flexibility of our nature fits us to receive new impressions, linked together by a certain secret analogy. We so readily perceive the affinity existing amongst all the forms of organic life, that although the sight of a vegetation similar to that of our native country might at first be most welcome to the eye, as the sweet familiar sounds of our mother tongue are to the ear, we nevertheless, by degrees, and almost imperceptibly, become familiarized with a new home and a new climate. As a true citizen of the world, man everywhere habituates himself to that which surrounds him ; yet fearful, as it were, of breaking the links of association that bind him to the home

* “This expression is taken from a beautiful description of forest scenery in ‘Paul and Virginia,' by Bernadin de Saint Pierre.”

[ocr errors]
« 이전계속 »