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ville Thomson to our Government to assist by the loan of a ship in a careful exploratiop of the deeper portions of the North Atlantic arose from the interest excited by the researches of a Swedish dredging expedition. England has, however, as indeed is only right, always been foremost in the investigation of the nature of the sea, its currents, depths, life, &c. English naturalists have been the most prominent in the use of the dredge for ascertaining the forms of life occurring on sea-bottoms; the most valuable soundings have been made by English navigators from the time of Ross onwards, and the art of manipulating submarine cables has been worked out by Englishmen. We are more interested in a thorough understanding of the sea than any other nation, and it is only reasonable, therefore, that our Government should take very decided steps in carrying on, and even originating, researches tending to such knowledge; and, being thus practically interested in the matter, the scientific problems connected with the sea, — so fundamental in geological speculation, so fertile in relation to the origin and nature of life,—naturally fall to our share for investigation ; and we, with our immense naval apparatus,—as a people with a Royal Society and a claim to a place in the scientific community,—are bound for our honor to take up these questions.

Let us recall briefly what are the results which the expeditions of the last three years have furnished. It had been a current belief among physical geographers that the temperature of the deepest portions of the sea was everywhere about 39° Fahr., sinking to that point as the thermometer descends from the warmer surface in equatorial regions, and ascending to that point as the thermometer is lowered from the colder surface of polar regions. But in his first exploration in the deep channel which lies between the north of Scotland and the Faroe Isles, Dr. Carpenter found, over a considerable area, at depths of 600 fathoms, a temperature of only 320 to 330 Fahr., the surface temperature being only about 520 ; in closely contiguous regions, at the same depths and with the same surface-temperature, the remarkable fact was observed that the temperature was not less than 47°. Coupled with this difference of temperature, there was found a difference of fauna,

the living things in the cold area being of a different type from, and less abundant than, those of the warm area, which resembled the forms occurring in the warmer temperate seas. This and subsequent confirmatory observations have been explained by Dr. Carpenter, by a theory of oceanic currents, which is of exceeding importance. Much influence has been attributed to surface currents, such as the Gulf Stream, in relation to climates and the equalization of the temperature of the globe. Dr. Carpenter suggests that the deep areas of cold water which he observed are currents of cooled water passing from the regions of polar ice to the equator,—the water warmed at the surface in the equatorial regions spreads to the polar regions, and being there rapidly cooled by the accumulated ice sinks, in virtue of its greater density, below the warm water continually arriving from the tropics, the constant displacement of cooled water by warm producing a constant current In this way a continual circulation is effected of a far more general nature, and proportionately more important than the limited surface currents with which we were previously acquainted. The analogy of the atmospheric circulation is entirely in favor of this theory, and simple experiments which we are every day making in heating apparatuses of various kinds, such as the hot-water pipes of our greenhouses, give us ample proof that the agents at work, viz., equatorial heat and polar cold, are causes capable of producing the results ascribed to them. Sir John Herschel, a short time before his death, expressed an opinion favorable to Dr. Carpenter's theory. If true, it will considerably modify the received doctrine of the dependence of our own climate, and of the amelioration of the temperature of the polar b^sin on an extension of the Gulf Stream ; it will also considerably modify the glacial doctrine of geologists, limiting its range in one direction, whilst vastly extending it in others; and it will have an important bearing on the rationale of those surface currents which are so important in navigation, and of which the explanation has hitherto been so difficult. The Baltic current, the Gibraltar current, and the Bosphorus current, have been rendered intelligible by the light of this theory, which Dr. Carpenter hopes further to confirm during the present summer. To extend the researches which led to these results into the great ocean beds of other parts of the world is clearly very desirable.

The existence of such diverse submarine climates side by side, as were observed in the North Atlantic, has also a great importance for the geologist, for were the sea-bottom in this part now to become dry land, we should find two very different looking deposits, containing two series of remains—really contemporaneous, but indicating such difference of conditions, that our present geological theories would lead us to class them as belonging to distinct successive periods, sufficiently separated to allow of climatic changes. It would be most interesting to ascertain if such diversity, and to what extent, is to be met with in other ocean beds. We are accustomed to see the kinds of living productions of various regions of the earth's surface limited by high mountain ranges, by breaks in the land surface, and by the course of rivers. Rivers often carry with them, along the whole course of their beds, a peculiar fauna, and it seems that we may regard the deep-ocean currents as rivers limited by watery barriers, spreading their special fauna, over considerable ranges of latitude, and separated by differences of temperature as impassable as, and far sharper in their restricting action than, mountainous elevations. To ascertain to what extent this distributing action of the deep-sea currents holds good, by extended researches in other and tiore distant ocean beds, is exceedingly! ii portant.

Apart from the question of ocean currents, the deep-sea explorations of the last three years have led to the discovery of abundant life at enormous depths in the ocean. Three hundred fathoms were supposed to be about the limit to which life extended, and in spite of a few observations, by means of soundings, which tended to falsify this opinion, naturalists believed that, in consequence of the diminution of light, and the great pressure of the superjacent water, animals and plants could not exist in what was called the abyssal zone of the ocean. Now we know from actual dredging of the bottom, that animals in considerable variety exist in the sea at a depth of at least three miles, under a pressure of three tons on every square inch, and probably at the greatest existing depths.

These great depths having been previously unexplored—as might be expected —new and most interesting forms, of life have been met with, even in the small area already examined. Many very beautiful sponges and certain star-fishes, of kinds most nearly allied to those of which we have remains in the chalk formation, have been obtained ; and it would appear probable that in these great depths we have the descendants of a series of forms which in past periods occupied the shallower parts of the sea, but have been gradually supplanted and forced -into these regions (certainly less favorable on the whole for a flourishing existence) by the action of changed conditions and the immigration of other groups or faunae. From this point of view the inhabitants of these deep regions may be compared to the arctic plants found on mountain heights, or to the representatives of the great extinct group of ganoid fishes which linger on in the retirement of some of the large African and American rivers. So remarkably does the life of the deep warmer areas of the North Atlantic correspond to that contained in the chalk deposit, that Prof. Wyville Thomson has observed that we may be said, even now, to be living in the cretaceous period. The oo/.e accumulating in these areas has the same character as chalk, being principally formed of the remains of small calcareous shells,—those of globigerina; whilst the sponges, echinoderms, and molluscs present the closest affinities to cretaceous forms. The conditions, under which the cretaceous beds were deposited have never entirely ceased, and though changing their area of operation, and probably much modified in ways to be yet clearly worked out,—in doing which the proper understanding of ocean currents and their causes must be fundamental,—they continue in operation over a wide area of the present sea-bed. A condition of the land or sea-bottom which once existed may be, it is conceivable, entirely destroyed, and with it its characteristic inhabitants, which either themselves become modified, or are completely supplanted by the incursions of the inhabitants of neighboring areas more fitted to the new conditions. The diversion or mingling of currents might bring about such a change by degrees in a sea-bed. On the other hand, instead of being entirely lost, the conditions of life operating over a given area might merely change their ground, wandering by degrees perhaps very far from their earlier site, with slight modification, and then, instead of remaining to be extinguished by competition with newly arriving inhabitants, the old fauna would move with its moving conditions (suppose in the case of the chalk fauna a moving warm current or currents), and would thus follow them, changing with their changes, developing with their renewed favor, or shrinking with their increasing unsuitability, until finally laid open by encroachment on a particular area to the inroads of a fauna more lilted to flourish under those conditions, now much modified by long and gradual changes, than they themselves : then they would become extinct.

Such speculations as these are suggested by the remarkable forms of life dredged up in a small portion of the deeper parts of the ocean. Were these researches extended to the depths of the Indian, Pacific, and Southern oceans, we cannot doubt that results of inconceivable interest would be obtained. What strange organisms might not pe brought to light!—what precious remnants of a lost world! The zoologist and the geologist would alike receive immense additions to their knowledge ; and whilst theories of the formation of the earth's crust and the past condition of the globe would obtain firmer basis, the connection of living forms of life with those which are extinct, and whose nature is

but partially known through their fossil remains, would be largely elucidated.

No private individual could possibly carry on the work which is so desirable. But a four years' circumnavigation voyage could, with slight expense to the country, be arranged by the Admiralty, and the accomplished investigator, whose researches made during the past three years we have briefly mentioned, is, we believe, ready to devote his services to such an undertaking.

The interest which is felt in the country by educated people in Dr. Carpenter's and his colleague's work is proved by the requests which they have received to recount their experiences in public lectures in various towns. That such employment as this has a good moral influence upon the Navy,—upon its credit with the country, and of our country with foreign nations,—cannot be doubted; whilst the increasing importance attached to the study of natural science as a part of education throughout the country demands an increased recognition and encouragement of its advanced objects by the State. An expedition such as it is proposed to organize,—certain to be fraught with such valuable results,—would not entail a greater expenditure, spread over three or four years, than that incurred in one year for the Biacas collection. Of course, the material obtained in such an expedition would be national property, and placed in the national collection.

Cornhill Magazine.
MARIAN MAY.

Marian May was our hamlet's pride,

Worthy a queen to be,
For of all the maids in the country side

Was none so fair as she.

Her hair was like silk and her eyes like wine,

Liquid and dark and deep; They sparkled and danced in the broad sunshine,

Or melted in rosy sleep.

Lovers by scores for her white hand sighed,

Of high and of low degree,
And many came riding from far and wide,

Her sweethearts fain to be.

The squire had plenty of golden store,

Such as for him was meet;
And he wished no better, and asked no more,

Than to lay it all at her feet.

But she put his gifts and his vows aside,
Laughing, and out spake she:
"I never was born for a rich man's bride,
So I cannot mate with thee."

The parson he came, with his face so grave,

Gentle and sleek and prim,
And said the best way her soul to save

Was to take and marry him.

But she only opened her eyes full wide,
Wondering, and quoth she,
"Were there never a man in the world beside,
You'd be far too good for me!"

The colonel he swore a right round oath—

"Little one, be my wife!
I've scars and a pension enough for both,

If you'll share a soldier's life."

He vowed that he would not be denied,

Low on his bended knee;
But she tossed her head with a pretty pride,

Said, "I never will wed with thee!"

Robin came back from the sea one day,

Out of the distant west,
And the child with whom he used to play,

A woman he clasped to his breast.

She sobbed and kissed, and she laughed and cried—
"Welcome, my love," said she;
"For woe or for weal, and whate'er betide,
I will fare the world through with thee!"

H. C. Merivale.

SIR JOHN 1

It is a good sign for England that the death of a scientific man like Sir John Herschel, although he had lived for many years in close retirement, had rarely been seen except by members of his own family and personal friends, and had long given over scientific work of the more serious kind, is felt as a great and national loss. High and low, rich and poor, lament the absence of one who has been to most of them little more than a name; first, because the dignity of a life spent in the study of nature is beginning to assert it

New Series.—Vol. XIV., No 4.

'Review.
ERSCHEL.

self; and, secondly, because in Sir John
Herschel the power of scientific obser-
vation was pre-eminently associated not
only with the power of appealing to tens
of thousands by his writings, but with all
those qualities which, when we find them
in a great man, make him universally be-
loved.

In attempting to give a sketch of a man who was so emphatically the son of his father, both in thought and work, it is im* possible to speak of one without referring to the other. Not only were they laborers

32

in the same vast field, but for many years of his life Sir John Herschel was engaged in researches which maybe looked upon as an extension of those commenced by his father. Born at Slough in 1792, he passed his childhood under the shadow of that giant telescope which his father's skill and indomitable perseverance had erected, and to which the liberality of the King, who endowed the father with a sum of 400/. a year, enabled him to devote all his energies. Here we may stop to remark upon the large amount of immortal work which has been done under analogous conditions. The names of Ptolemy, Galileo, and Tychp at once occur to us as having been similarly aided in the very science which the Herschels have so brilliantly cultivated. How much work is still remaining undone in the presence of exactly the opposite conditions now, when the mime inutile of Louis Quatorze is clean forgotten, abstract science is all but an outcast, and " Her Majesty's Government "—the modern King—while indeed it performs its duty in buying pictures, does nothing for the furtherance of natural knowledge, and all too little for its distribution!

John Herschel, indirectly profiting without doubt by this magnificent endowment, and reared in an atmosphere of wonderful discoveries, went to Eton and subsequently to St. John's College, Cambridge, rilled with an intense love of his father's pursuits; and, as a result of his early training and his own mental powers, he came out senior wrangler and first Smith's prizeman in 1813, with Peacock as second wrangler, and Babbage—backing out of the battle of giants—captain of the poll. In the same year he sent his first paper to the Royal Society.

In 1816 we find him engaged in astronomical work in one of those prolific fields of observation which his father had opened up to an astonished world. The fixed stars, on which the prestige of immutability had rested after Galileo had snatched it from the sun, had been found to include some which appeared double or treble, not because they were in the same line from the eye, but because they were physically connected, revolving round each other, or rather round a common centre of motion, as our earth does round the sun. This, and an examination of the nebula; and clusters discovered by his

father, engaged much of Herschel's attention for some years, and in conjunction with Sir James South he presented a paper to the Royal Society, embodying upwards of 10,000 observations on the double stars, which was printed in 1824; and in 1832 a catalogue of 2,000 nebulas and clusters was also printed in the Philosophical Transactions.

But this by no means represents the sum total of his activity during this period. The mathematical papers communicated in 18I3 and the following years to the Philosophical Transactions were soon supplemented by papers on chemistry, many of which appeared in the Edinburgh Philosophical Journal about 1819. In 1828 physical science was added to chemical science, and Herschel broke ground in his many researches on optical questions by a paper in the Philosophical Transactions on the action of crystallized bodies in homogeneous light; while, with astonishing versatility, in 1824 he had sufficiently mastered the subject of electricity to deliver the Bakerian Lecture before the Royal Society on the motion produced in fluid conductors when transmitting the electric current. We note these incidents merely to show Herschel's many-sidedness in his scientific work, not by any means to exhaust its list; for this many pages in the Royal Society's Index of Scientific Papers would have to be quoted. There is one item of what may be termed his miscellaneous work to which we must specially refer In 1822 we find him investigating the spectra of colored flames, and these researches were carried on, at intervals at all events, till 1827, when he wrote, "The colors thus contributed by different objects to flame afford in many cases a ready and neat way of detecting extremely minute quantities of them." Here we find spectrum analysis almost stated in terms, and yet, although Herschel, Brewster, and Fox Talbot were on the track of the most brilliant discovery of our age, the clue was lost and little came of their labors. It is one thing to make observations, and another to plan and conduct researches in a perfectly untrodden field; and it is no disparagement of Herschel to make this remark in connection with his experiments on spectrum analysis, for although he would certainly, as a result of these experiments, have anticipated Kirchhoff and

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