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tion of fossil animals our author gives this elegant illustration, borrowed from the Dean of Westminster :

'In the lower Jura formation (lias of Lyme Regis), the preservation of the ink-bag of the cuttlefish is so perfect, that the same material which myriads of years ago served to defend the animal by concealing it from its enemies, yields an excellent colour (sepia) with which its portrait may be drawn.'—p. 285.

Our author seems disposed to adopt Agassiz' opinion, that with one single exception no fossil fish has been found in any part of the transition, secondary, or tertiary series, which is specifically identical with any living specimen; and below the chalk the genera are all extinct (p. 288). But in contrast with the statement (not in contradiction to it) he places the discovery of Ehrenberg, that whole masses of the chalk formation are actually composed of microscopic shells identical with those of our present ocean in temperate latitudes. Whence he infers, that the term Eocene cannot be justly applied to tertiary formations, since the dawn of existing species is already to be found much lower.

The development of fossil geology is necessarily brief :* in p. 291 we have a condensed enumeration of strata in the order of superposition. The vexed question of diluvial phenomena and transported blocks is left almost untouched; our author merely intimates in one place (p. 299) his preference of the old theory of Von Buch, that they are due to currents of water caused by the sudden elevation of mountain chains, rather than to icebergs or any other cause.

After mentioning with deserved praise Elie de Beaumont's maps of the comparative extent of land and sea at different geological epochs, Humboldt thus sums up :

The result of the researches on the relative areas of the dry land is this ;--that in the earliest times (the Silurian and Devonian Transition Epochs) and in the oldest secondaries, the dry land, the surface covered with plants, was confined to detached islands; that at later epochs these islands were united, and the deeply indented bays became inclosed as lakes; that at last when the mountain chains of the Pyrenees, Apennines, and Carpathians arose, about the period of the older tertiary rocks, great continents appeared, having almost their present dimensions. In the Silurian period, as well as that when Cycadeæ and gigantic Saurians abounded, there might be less land between one pole and the other than we now see in the South Sea and Indian Ocean. How this excess of water, together with other causes, acted to produce a higher and more uniform temperature, will be shown hereafter. We must however remark here,

* The precise geological limit of the great classes of fossils is always interesting. It at present stands thus: Fish begin with the Silurian rocks and ascend uninterruptedly to the tertiary formations inclusive. Saurians commence in the magnesian limestone (zechstein); Mammalia in the Jura formation; Birds in the older chalk.

with reference to the gradual growth by agglutination of the newly ele. vated spaces of dry land, that shortly before the revolutions which after longer or shorter pauses occasioned the sudden destruction in the diluvial period of so many vertebrated animals, portions of the present continental masses were still completely separated from one another. There prevails in South America and in Australia a great resemblance between the living and extinct animals. In New Holland we find fossil remains of the kangaroo; in New Zealand, half-fossil bones of a huge ostrich-like bird, Owen's Dinornis, which is nearly related to the living Apteryx, but little so to the recently extinct Dodo of the island of Rodriguez.'— Kosmos, p. 303.

Passing from pure geology, our author next contributes some interesting information on the forms of continents, and on the struggle between the sea and land to which they are due. Relative changes of level are discussed (p. 312, &c.), particularly those in Sweden and of the Bay of Naples, which he considers may be due to great internal pressure, or to the irregularity of expansion of great masses by central heat-an idea due to Breislak, though lately revived by Babbage and Bischoff.* The anomalous levels of the Dead Sea and Caspian are discussed, and the leading phenomena of the ocean, such as its temperature, saltness, tides, and currents, very summarily enumerated (pp. 321–329).

The next topic is meteorology, or the phenomena of the atmosphere, including climate, which has always been, we should say, the subject of predilection with Humboldt, nor perhaps has he done anything so likely to perpetuate his fame as the construction of isothermal lines, and his subsequent researches on their modifications and inflections, including the influence of season and of height. In such processes of first generalization of isolated facts, so as to obtain empirical laws, we find the undoubted forte of this distinguished traveller; and the patience and skill with which he has endeavoured to raise ineteorology to the position of an exact science are deserving of all praise. There is, however, little in this part of the volume (pp. 332–362) not already well known to readers of his former writings.

Finally, the picture of the physical world is completed by a glance at the wonders of organic life. Animal life, says Humboldt, characterizes the ocean; vegetables, the land; nor could he better illustrate this fact than by a curious extract from Ehren

* With reference to the rise of the coast of Sweden, it seems to us that our author's too marked partiality for everything done by an eminent friend, has led him in Note 20, p. 473, to treat Playfair's prior and admirable ex positions of the phenomena (in the Huttonian Theory, Art. 391, &c.) as being no real anticipation. He so treats them because they were entirely unknown to our great geognost (Von Buch), and have exercised no intiuence on the progress of Physical Geography.' The first of these assertions may be correct, but we respectfully demur to the second.

berg, berg, giving the latest results of his successful and brilliant career of discovery :

There not only exists an invisibly minute, microscopic life in the vicinity of either Pole, far beyond where larger animals have ceased to exist; but the microscopic creatures of the Southern Sea collected in the Antarctic Voyage of Sir James Ross, include an unsuspected abundance of hitherto perfectly unknown and often most beautiful structures. Even in the residuum of the melted ice which floats in rounded fragments in latitude 78° 10', were discovered above fifty species of siliceous shelled Polygastria and Coscinodisks, with their green ovaries, therefore undoubtedly living and successfully contending with the extreme cold. In Erebus Bay there were drawn up with the sounding-lead from a depth of from 1242 to 1620 feet, not less than 68 siliceous-shelled Polygastria and Phytolitharia, and amongst them a single calcareous-shelled Polythalamia.'-Kosmos, pp. 369, 370.

The discoveries of the German microscopist are amongst the most striking of our time. Not content with peopling the depths of even the Polar seas with myriads of living beings, he traces their remains amidst the solid rocks of our globe, where they not only characterize but constitute whole formations. We know not whether the element of fire may not one day reveal microscopic phænixes to our astonished gaze, but the air at least is peopled with its legions, and in the dusty rain which sometimes falls in the open ocean Ehrenberg has discovered remains of eighteen polygastric animalcula (p. 373).

In the few remaining pages of the volume before us, Baron Humboldt treats of the geographical distribution of plants and animals; he touches with caution (p. 378) on the vexed question of generation and the origin of animal organization; and sums up with a brief notice of the natural history of man, whom he (like Dr. Pritchard) pronounces to belong (p. 379) to a single species.

In closing this volume, sufficiently complete in itself, although intended as a precursor to others, we cannot but repeat our expression of unfeigned admiration at the perseverance and research which it displays,—the generally happy selection of facts and skill in their combination, together with the ample and learned references to authorities in the notes. All this would be admirable from a person of any age, but in the work of a more than Septuagenarian it is really astonishing. It is not a musty collection of the gleanings of a life of hard reading, but bears within itself ample evidence of the freshness and even rapidity of its composition. A vast majority of the references are to works and memoirs of the last ten years, and even less. It was only in February, 1843, that our author dismissed from his hands

his three volumes on Central Asia, and this work appears to have been chiefly written since.

Possibly the struggle for novelty has been carried a little too far. A picture of the (so-called) natural sciences as they are, cannot be constructed solely from the annals of contemporary discovery. The book of nature is a roll extended from year to year, but of which the earlier part, though blotted and altered, is not expunged or useless. The facts of science form a diverging series, of which each term is larger than its predecessor, yet not so immeasurably so as to allow all that precede to be neglected in comparison of it. Baron Humboldt, indeed, promises a history of science in a future volume; but he seems to us to have anticipated a great deal of it in the present one. The notes contain much curious, perhaps rather too elaborate learning, on the acquirements of the ancients, and also (what is more germane to the matter) on the discoveries of the 16th and 17th centuries. But the 18th century seems to have been forgotten, and the uninformed reader would, we fear, form an undue estimate of the relative importance of contemporary discoveries, distinguished as they undoubtedly are.

But we have yet another remark, which justice requires us to make, without meaning at all to detract from the cordial expression of approbation which we have pronounced. Though our author disclaims the intention (Preface, p. xiv.) of deciding claims of priority in scientific discoveries, it would be quite impossible to avoid them in a work like the present. Now on questions of individual or of national claims, Baron Humboldt will be tried by a severer standard of impartiality than most writers. His European reputation, his European correspondence, his extensive knowledge of languages, his liberal principles, his generous temper, even the fact of his having been almost equally domiciled in two countries, speaking and writing in French and German with equal facility ;on all these accounts, more perhaps than is reasonable will be and is expected of the author of Kosmos, a work, the greatness of whose scheme seems to address indifferently all civilized nations, and students in all departments.

Neither France nor Germany has any right to complain of the share which Humboldt has assigned to them in the great struggle for physical discovery. But we cannot rise from the careful perusal of this elaborate work without feeling that our own country has come off second, or rather third, best. The physics have (it seems to us) been written for the longitude of Paris, and the geology for that of Berlin; and no one, we think, who is conversant with the scientific circles of those capitals, can fail to see that the selection of topics and

of

of authors is tinged with the unconscious prejudices of local opinion.

In saying so much (and we could not feel ourselves justified in saying less), we are far from imputing to Baron Humboldt any motive less amiable than a desire to gratify distinguished contemporaries whom a less noble-minded person might have regarded rather with jealousy than with deference. To his ancient ally, Von Buch, especially this deference seems to surpass what could reasonably be expected or wished. The whole of the geological, and some other relative parts of the work, are not merely filled with citations in flattering terms from the writings of the greatest geologist of our time, but whether in matters of fact or in great theories, in trivial or important coincidences of opinion, nay, even in what is pointedly omitted or gently allowed to subside into neglect, the geological reader traces so exact a transcript of the well-known and stereotyped opinions of Von Buch, that he feels as if our author had forgotten his individuality of opinion in the anxious desire to applaud and flatter his friend.* Agreeing as we do entirely in a great many of these views, and entertaining indeed an exalted opinion of the sagacity acquired by the great Prussian geologist during a life spent with nature, and now on the verge of fourscore, we are far from wishing Humboldt's doctrines to have been different; we only wish that we had had a more impartial picture of his own convictions, and that a little more notice had been taken of contemporary, even if less distinguished labourers. If we recollect what has been done in England for modern geology—what is imperishably inscribed in the history of the science by its nomenclature—the members, deceased and alive, of the Geological Society of London might have reasonably expected to fill a more prominent place in the scientific history of the last forty years. Why is it that uneuphonious local names attached to certain rocky beds by an obscure mineral surveyor in England, and by his more cultivated successors, have become household words in every language of Europe ?-Clunch clay and Kimmeridge clay, Portland stone and Coral Rag, and more lately Silurian and Devonian rocks—are terms known from the banks of the Wolga to those of the St. Lawrence, from Newfoundland to Patagonia, from Norway to New Holland; and even our fastidious neighbours in Europe have been constrained to Gallicise these barbarous terms. It is all well to signalise

* We have been disagreeably struck with the complimentary epithets which Baron Humboldt lavisbes so indiscriminately upon the authors whom he cites, especially upon his countrymen. These possibly regard them in no other light than they would the conventional ‘hochwohlgeboren' of German correspondents. But the thing conveys to an Englishman a different impression.

Hooke

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