Chapter IX: Section III: Time of "the Masters." (2)

273. The causes of the different effects of air on stone must be numerous, and the investigation of them excessively difficult. With regard, first, to rocks _en masse_, if their structure be crystalline, or their composition argillaceous, the effect of the air will, I think, ordinarily, be found injurious. Thus, in granite, which has a kind of parallelogrammatic cleavage, water introduces itself into the fissures, and the result, in a sharp frost, will be a disintegration of the rocks _en masse_; and, if the felspar be predominant in the composition of the granite, it will be subject to a rapid decomposition. The morvine of some of the Chamouni and Allée Blanche glaciers is composed of a white granite, being chiefly composed of quartz and felspar, with a little chlorite. The sand and gravel at the edge of these glaciers appears far more the result of decomposition than attrition. All finely foliated rocks, slates, etc., are liable to injury from frost or wet weather. The road of the Simplon, on the Italian side, is in some parts dangerous in, or after, wet weather, on account of the rocks of slate continually falling from the overhanging mountains above; this, however, is mere disintegration, not decomposition. Not so with the breccias of Central Switzerland. The rock of Righi is composed of pebbles of different kinds, joined by a red argillaceous gluten. When this rock has not been exposed to the air, it is very hard: you may almost as easily break the pebbles as detach them from their matrix; but, when exposed for a few years to wind and weather, the matrix becomes soft, and the pebbles may be easily detached. I was struck with the difference between this rock and a breccia at Epinal, in France, where the matrix was a red sandstone, like that of the cathedral at Basle. Here, though the rock had every appearance of having been long exposed to the air, it was as hard as iron; and it was utterly impossible to detach any of the pebbles from the bed: it was difficult even to break the rock at all. I cannot positively state that the gluten in these sandstones is calcareous, but I suppose it to have been so. Compact calcareous rock, as far as I remember, appears to be subject to no injury from the weather. Many churches in Italy, and almost the whole cities of Venice and Genoa, are built of very fine marble; and the perfection of the delicate carvings, however aged, is most remarkable. I remember a church, near Pavia, coated with the finest and most expensive marbles; a range of beautifully sculptured medallions running round its base, though old, were as distinct and fine in their execution as if they had just come out of the sculptor's studio. If, therefore, the gluten of the sandstone be either calcareous or siliceous, it will naturally produce the effect above alluded to, though it is certainly singular that the stone should be soft when first quarried. Sandstone is a rock in which you seldom see many cracks or fissures in the strata: they are generally continuous and solid. Now, there may be a certain degree of density in the mass, which could not be increased without producing, as in granite, fissures running through it: the particles may be supposed to be held in a certain degree of tension, and there may be a tendency to what the French call _assaissement_ (I do not know the English term), which is, nevertheless, resisted by the stone _en masse_; and a quantity of water may likewise be held, not in a state of chemical combination, but in one of close mixture with the rock. On being broken or quarried, the _assaissement_ may take place, the particles of stone may draw closer together, the attraction become stronger; and, on the exposure to the air, the water, however intimately combined, will, in a process of years, be driven off, occasioning the consolidation of the calcareous, and the near approach of the siliceous, particles, and a consequent gradual induration of the whole body of the stone. I offer this supposition with all diffidence; there may be many other causes, which cannot be developed until proper experiments have been made. It would be interesting to ascertain the relative hardness of different specimens of sandstone, taken from different depths in a bed, the surface of which was exposed to the air, as of specimens exposed to the air for different lengths of time.

J. R.

HERNE HILL, _July 25, 1836._

FOOTNOTES:

[Footnote 27: London's _Magazine of Natural History_, Vol. vii., pp. 644-5. The note was illustrated by engravings from two sketches by the author of the Aiguille de Servoz and of the Aiguille Dru, and by a diagram explanatory of its last sentence but one.--ED.]

[Footnote 28: "A small neat copy of a sketch carefully taken on the spot," which, according to the editor of the magazine, accompanied this communication, was not, however, published. See the magazine.--ED.]

[Footnote 29: Loudon's _Magazine of Natural History_, Vol. ix., No. 65, pp. 488-90.--ED.]

[Footnote 30: The question here discussed was originally asked in the magazine (Vol. ix., pp. 379-80) by Mr. W. Perceval Hunter with reference to the condition of Bodiam Castle, in Sussex.--ED.]

OBSERVATIONS ON THE CAUSES WHICH OCCASION THE VARIATION OF TEMPERATURE BETWEEN SPRING AND RIVER WATER.--BY J. R.[31]

274. The difference in temperature between river and spring water, which gives rise to the query of your correspondent Indigena (p. 491),[32] may be the result of many causes, the principal of which is, however, without doubt, the interior heat of the earth. It is a well known fact, that this heat increases in a considerable ratio as we descend, making a difference of several degrees between the temperature of the earth at its surface and at depths of 500 or 600 feet; raising, of course, the temperature of all springs which have their source at even moderate depths, and entirely securing them from the effects of frost, which, it is well known, cannot penetrate the earth to a greater depth than 3 or 4 ft.

275. Many instances might be given of the strong effect of this interior heat. The glaciers of the Alps, for instance, frequently cover an extent of three or four square leagues, with a mass of ice 400, 500, or even 600 feet deep, thus entirely preventing the access of exterior heat to the soil; yet the radiation of heat from the ground itself is so powerful as to dissolve the ice very rapidly, and to occasion streams of no inconsiderable size beneath the ice, whose temperature, in summer, is, I believe, as far as can be ascertained, not many degrees below that of streams exposed to the air; and the radiation of heat from the water of these streams forms vaults under the ice, which are frequently 40 ft. or 50 ft. above the water; and which are formed, as a glance will show, not by the force of the stream, which would only tear itself a broken cave sufficient for its passage, but by the heat which radiates from it, and gives the arch its immense height, and beautifully regular form.

These streams continue to flow in winter as well as in summer, although in less quantity; and it is this process which chiefly prevents the glacier from increasing in size; for the melting at the surface is, in comparison, very inconsiderable, even in summer, the wind being cold, the sun having little power, and slight frosts being frequent during the night. It is also this melting beneath the ice (subglacial, suppose we call it) which loosens the ice from the ground, and occasions, or rather permits, the perpetual downward movement, with which

"The glacier's cold and restless mass
Moves onward day by day."

276. But more forcible and striking evidence is afforded by experiments made in mines of great depth. Between 60 ft. and 80 ft. down, the temperature of the earth is, I believe, the same at all times and in all places; and below this depth it gradually increases. Near Bex, in the Valais, there is a perpendicular shaft 677 ft. deep, or about 732 ft. English, with water at the bottom, the temperature of which was ascertained by Saussure. He does not tell us whether he used Réaumur's or the centesimal thermometer; but the result of his experiment was this:--In a lateral gallery, connected with the main shaft, but deserted, and, therefore, unaffected by breath or the heat of lamps, at 321 ft. 10 in. below the surface, the temperature of the water and the air was exactly the same, 11-1/2°; or, if the centesimal thermometer was used, 52-4/5 Fahr.; if Réaumur's, 57-7/8 Fahr.

277. In another gallery, 564 feet below the surface, the water and air had likewise the same temperature, 12-1/2°, either 54-4/5 or 6O-1/4 Fahr. The water at the bottom, 677 feet, was 14°, 57-1/2 or 63-1/4 Fahr. The ratio in which the heat increases, therefore, increased as we descend, since a difference of 113 feet between the depth of the bottom of the shaft and the lowest gallery makes a greater difference in temperature than the difference of 243 feet between the lowest and upper gallery. This heat is the more striking when it is considered that the water is impregnated with salt; indeed, Saussure appears inclined to consider it accidental, perhaps occasioned by the combustion of pyrites, or other causes in the interior of the mountain ("Voyages dans les Alpes," tom. iv., c. 50). All experiments of this kind, indeed, are liable to error, from the frequent occurrence of warm springs, and other accidental causes of increase in temperature. The water at the bottom of deep lakes is always found several degrees colder than the atmosphere, even when the water at the surface is warmer: but that may be accounted for by the difference in the specific gravity of water at different temperatures; and, as the heat of the sun and atmosphere in summer is greater than the mean heat of the earth at moderate depths, the water at the bottom, even if it becomes of the same heat with the earth, must be colder than that at the surface, which, from its exposure to the sun, becomes frequently warmer than the air. The same causes affect the temperature of the sea; and the greater saturation of the water below with salt renders it yet more susceptible of cold. Under-currents from the poles, and the sinking of the water of low temperature, which results from the melting of the icebergs which float into warmer latitudes, contribute still farther to lower the temperature of the deep sea. If, then, the temperature of the sea at great depths is found not many degrees lower than that at the surface, it would be a striking proof of the effect produced by the heat of the earth; but I am not aware of the results of the experiments which have been made on this subject.

278. We must, then, rest satisfied with the well-ascertained fact, that the temperature of the earth, even at depths of a few feet, never descends, in temperate latitudes, to the freezing point; and that at the depth of 60 feet it is always the same, in winter much higher, in summer considerably lower, than that of the atmosphere. Spring water, then, which has its source at a considerable depth, will, when it first rises, be of this mean temperature; while, after it has flowed for some distance, it becomes of the temperature of the atmosphere, or, in summer, even warmer, owing to the action of the sun, both directly and reflected or radiated from its bottom. Besides this equable temperature in the water itself, spring or well water is usually covered; and, even if exposed, if the well is very deep, the water will not freeze, or at least very slightly; for frost does not act with its full power, except where there is a free circulation of air. In open ponds, wherever bushes hang over the water, the ice is weak. Indigena's supposition, that there are earthy particles in river water, which render it more susceptible of cold than spring water, cannot be true; for then the relative temperatures would be the same in winter and in summer, which is not the case; and, besides, there are frequently more earthy particles in mineral springs, or even common land springs, than in clear river water, provided it has not been fouled by extraneous matter; for it has a tendency to deposit the earthy particles which it holds in suspension.

279. It is evident, also, that the supposition of Mr. Carr (Vol. v., p. 395) relative to anchor frosts, that the stones at the bottom acquire a greater degree of cold, or, to speak more correctly, lose more heat, than the water, is erroneous. J. G. has given the reasons at p. 770; and the glaciers of Switzerland afford us an example. When a stone is deposited on a glacier of any considerable size, but not larger than 1 foot or 18 inches in diameter, it becomes penetrated with the heat of the sun, melts the ice below it, and sinks into the glacier. But this effect does not cease, as might be supposed, when the stone sinks beneath the water which it has formed; on the contrary, it continues to absorb heat from the rays of the sun, to keep the water above it liquid by its radiation, and to sink deeper into the body of the glacier, until it gets down beyond the reach of the sun's rays, when the water of the well which it has formed is no longer kept liquid, and the stone is buried in the ice. In summer, however, the water is kept liquid; and circular wells, formed in this manner, are of frequent occurrence on the glaciers, sometimes, in the morning, covered by a thin crust of ice.

Thus, the stones at the bottom of streams must tend to raise, rather than lower, this temperature. Is it possible that, in the agitation of a stream at its bottom, if violent, momentary and minute vacua may be formed, tending to increase the intensity of the cold?

HERNE HILL, _Sept. 2, 1836._

FOOTNOTES:

[Footnote 31: London's _Magazine of Natural History_, vol. ix., pp. 533-536.--ED.]

[Footnote 32: The query was as follows:--

_An Inquiry for the Cause of the Difference in Temperature of River Water and Spring Water, both in Summer and Winter._--In the summer time the river water is much warmer than that from a spring; during the severe frosts of winter it is colder; and when the stream is covered over with ice, the spring, that is, well or pump water is unaffected by frost. Does this difference proceed from the exposure of the surface of the river water, in summer, to the sun's direct influence, and, in winter, to that of frost; while the well water, being covered, is protected from their power? Or is there in river water, from the earthy particles it contains, a greater susceptibility of heat and cold?--_Indigena_. _April 19, 1836._--ED.]

METEOROLOGY.[33]

280. The comparison and estimation of the relative advantages of separate departments of science is a task which is always partially executed, because it is never entered upon with an unbiased mind; for, since it is only the accurate knowledge of a science which can enable us to present its beauty, or estimate its utility, the branches of knowledge with which we are most familiar will always appear the most important. The endeavor, therefore, to judge of the relative _beauty_ or _interest_ of the sciences is utterly hopeless. Let the astronomer boast of the magnificence of his speculations, the mathematician of the immutability of his facts, the chemist of the infinity of his combinations, and we will admit that they all have equal ground for their enthusiasm. But the highest standard of estimation is that of utility. The far greater proportion of mankind, the uninformed, who are unable to perceive the beauty of the sciences whose benefits they experience, are the true, the just, the only judges of their relative importance. It is they who feel what impartial men of learning know, that the mass of general knowledge is a perfect and beautiful body, among whose members there should be no schism, and whose prosperity must always be greatest when none are partially pursued, and none unduly rejected. We do not, therefore, advance any proud and unjustifiable claims to the superiority of that branch of science for the furtherance of which this society has been formed over all others; but we zealously come forward to deprecate the apathy with which it has long been regarded, to dissipate the prejudices which that apathy alone could have engendered, and to vindicate its claims to an honorable and equal position among the proud thrones of its sister sciences. We do not bring meteorology forward as a pursuit adapted for the occupation of tedious leisure, or the amusement of a careless hour. Such qualifications are no inducements to its pursuit by men of science and learning, and to these alone do we now address ourselves. Neither do we advance it on the ground of its interest or beauty, though it is a science possessing both in no ordinary degree. As to its beauty, it may be remarked that it is not calculated to harden the mind it strengthens, and bind it down to the measurement of magnitudes and estimation of quantities, destroying all higher feelings, all finer sensibilities: it is not to be learned among the gaseous exhalations of the deathful laboratory; it has no dwelling in the cold caves of the dark earth; it is not to be followed up among the charnel houses of creation. But it is a science of the pure air, and of the bright heaven; its thoughts are amidst the loveliness of creation; it leads the mind, as well as the eye, to the morning mist, and the noonday glory, and the twilight-cloud, to the purple peace of the mountain heaven, to the cloudy repose of the green valley; now expatiating in the silence of stormless ether, now on the rushing of the wings of the wind. It is indeed a knowledge which must be felt to be, in its very essence, full of the soul of the beautiful. For its interest, it is universal, unabated in every place, and in all time. He, whose kingdom is the heaven, can never meet with an uninteresting space, can never exhaust the phenomena of an hour; he is in a realm of perpetual change, of eternal motion, of infinite mystery. Light and darkness, and cold and heat, are to him as friends of familiar countenance, but of infinite variety of conversation; and while the geologist yearns for the mountain, the botanist for the field, and the mathematician for the study, the meteorologist, like a spirit of a higher order than any, rejoices in the kingdoms of the air.

281. But, as we before said, it is neither for its interest, nor for its beauty, that we recommend the study of meteorology. It involves questions of the highest practical importance, and the solution of which will be productive of most substantial benefit to those classes who can least comprehend the speculations from which these advantages are derived. Times and seasons and climates, calms and tempests, clouds and winds, whose alternations appear to the inexperienced mind the confused consequences of irregular, indefinite, and accidental causes, arrange themselves before the meteorologist in beautiful succession of undisturbed order, in direct derivation from definite causes; it is for him to trace the path of the tempest round the globe, to point out the place whence it arose, to foretell the time of its decline, to follow the hours around the earth, as she "spins beneath her pyramid of night," to feel the pulses of ocean, to pursue the course of its currents and its changes, to measure the power, direction, and duration of mysterious and invisible influences, and to assign constant and regular periods to the seedtime and harvest, cold and heat, summer and winter, day and night, which we know shall not cease, till the universe be no more. It may be thought we are exaggerating the effects of a science which is yet in its infancy. But it must be remembered that we are not speaking of its attained, but of its attainable power: it is the young Hercules for the fostering of whose strength the Meteorological Society has been formed.

282. There is one point, it must now be observed, in which the science of meteorology differs from all others. A Galileo, or a Newton, by the unassisted workings of his solitary mind, may discover the secrets of the heavens, and form a new system of astronomy. A Davy in his lonely meditations on the crags of Cornwall, or in his solitary laboratory, might discover the most sublime mysteries of nature, and trace out the most intricate combinations of her elements. But the meteorologist is impotent if alone; his observations are useless; for they are made upon a point, while the speculations to be derived from them must be on space. It is of no avail that he changes his position, ignorant of what is passing behind him and before; he desires to estimate the movements of space, and can only observe the dancing of atoms; he would calculate the currents of the atmosphere of the world, while he only knows the direction of a breeze. It is perhaps for this reason that the cause of meteorology has hitherto been so slightly supported; no progress can be made by the most gigantic efforts of a solitary intellect, and the co-operation demanded was difficult to obtain, because it was necessary that the individuals should think, observe, and act simultaneously, though separated from each other by distances on the greatness of which depended the utility of the observations.

283. The Meteorological Society, therefore, has been formed, not for a city, nor for a kingdom, but for the world. It wishes to be the central point, the moving power of a vast machine, and it feels that unless it can be this, it must be powerless; if it cannot do all, it can do nothing. It desires to have at its command, at stated periods, perfect systems of methodical and simultaneous observations,--it wishes its influence and its power to be omnipotent over the globe, so that it may be able to know, at any given instant, the state of the atmosphere at every point on its surface. Let it not be supposed that this is a chimerical imagination, the vain dream of a few philosophical enthusiasts. It is co-operation which we now come forward to request, in full confidence, that if our efforts are met with a zeal worthy of the cause, our associates will be astonished, _individually_, by the result of their labors in a body. Let none be discouraged because they are alone, or far distant from their associates. What was formerly weakness will now have become strength. Let the pastor of the Alps observe the variations of his mountain winds; let the voyagers send us notes of the changes on the surface of the sea; let the solitary dweller in the American prairie observe the passages of the storms, and the variations of the climate; and each, who alone would have been powerless, will find himself a part of one mighty mind, a ray of light entering into one vast eye, a member of a multitudinous power, contributing to the knowledge, and aiding the efforts, which will be capable of solving the most deeply hidden problems of nature, penetrating into the most occult causes, and reducing to principle and order the vast multitude of beautiful and wonderful phenomena by which the wisdom and benevolence of the Supreme Deity regulates the course of the times and the seasons, robes the globe with verdure and fruitfulness, and adapts it to minister to the wants, and contribute to the felicity, of the innumerable tribes of animated existence.

OXFORD UNIVERSITY.

FOOTNOTES:

[Footnote 33: From the "Transactions of the Meteorological Society," Vol. i., pp. 56-9 (London, 1839). The full title of the paper was "Remarks on the Present State of Meteorological Science." The Society was instituted in 1823, but appears to have published no previous transactions.--ED.]

ON TREE TWIGS.[34]

284. The speaker's purpose was to exhibit the development of the common forms of branch, in dicotyledonous trees, from the fixed type of the annual shoot. Three principal modes of increase and growth might be distinguished in all accumulative change, namely:--

1. Simple aggregation, having no periodical or otherwise defined limit, and subject only to laws of cohesion and crystallization, as in inorganic matter.

2. Addition of similar parts to each other, under some law fixing their limits and securing their unity.

3. Enlargement, or systematic change in arrangement, of a typical form, as in the growth of the members of an animal.

285. The growth of trees came under the second of these heads. A tree did not increase in stem or boughs as the wrist and hand of a child increased to the wrist and hand of a man; but it was built up by additions of similar parts, as a city is increased by the building of new rows of houses.

Any annual shoot was most conveniently to be considered as a single rod, which would always grow vertically if possible.

Every such rod or pillar was, in common timber trees, typically either polygonal in section, or rectangular.

If polygonal, the leaves were arranged on it in a spiral order, as in the elm or oak.

If rectangular, the leaves were arranged on it in pairs, set alternately at right angles to each other.

Intermediate forms connected each of these types with those of monocotyledonous trees. The structure of the _arbor vitæ_ might be considered as typically representing the link between the rectangular structure and that of monocotyledons; and that of the pine between the polygonal structure and that of monocotyledons.

Every leaf during its vitality secreting carbon from the atmosphere, with the elements of water, formed a certain quantity of woody tissue, which extended down the outside of the tree to the ground, and farther to the extremities of the roots. The mode in which this descending masonry was added appeared to depend on the peculiar functions of cambium, and (the speaker believed) was as yet unexplained by botanists.

286. Every leaf, besides forming this masonry all down the tree, protected a bud at the base of its own stalk. From this bud, unless rendered abortive, a new shoot would spring next year. Now, supposing that out of the leaf-buds on each shoot of a pentagonal tree, only five at its extremity or on its side were permitted to develop themselves, even under this limitation the number of shoots developed from a single one in the seventh year would be 78,125. The external form of a healthily grown tree at any period of its development was therefore composed of a mass of sprays, whose vitality was approximately distributed over the _surface_ of the tree to an equal depth. The branches beneath at once supported, and were fed by, this orbicular field, or animated external garment of vegetation, from every several leaf of which, as from an innumerable multitude of small green fountains, the streams of woody fiber descended, met, and united as rivers do, and gathered their full flood into the strength of the stem.

287. The principal errors which had been committed by artists in drawing trees had arisen from their regarding the bough as ramifying irregularly, and somewhat losing in energy towards the extremity; whereas the real boughs threw their whole energy, and multiplied their substance, towards the extremities, ranking themselves in more or less cup-shaped tiers round the trunk, and forming a compact united surface at the exterior of the tree.

288. In the course of arrival at this form, the bough, throughout its whole length, showed itself to be influenced by a force like that of an animal's instinct. Its minor curves and angles were all subjected to one strong ruling tendency and law of advance, dependent partly on the aim of every shoot to raise itself upright, partly on the necessity which each was under to yield due place to the neighboring leaves, and obtain for itself as much light and air as possible. It had indeed been ascertained that vegetable tissue was liable to contractions and expansion (under fixed mechanical conditions) by light, heat, moisture, etc. But vegetable tissue in the living branch did not contract nor expand under external influence alone. The principle of life manifested itself either by contention with, or felicitous recognition of, external force. It accepted with a visible, active, and apparently joyful concurrence, the influences which led the bough towards its due place in the economy of the tree; and it obeyed reluctantly, partially, and with distorted curvatures, those which forced it to violate the typical organic form. The attention of painters of foliage had seldom been drawn with sufficient accuracy to the lines either of branch curvature, or leaf contour, as expressing these subtle laws of incipient volition; but the relative merit of the great schools of figure design might, in absence of all other evidence, be determined, almost without error, by observing the precision of their treatment of leaf curvature. The leaf-painting round the head of Ariosto by Titian, in the National Gallery, might be instanced.

289. The leaf thus differed from the flower in forming and protecting behind it, not only the bud in which was the form of a new shoot like itself, but a piece of permanent work, and produced substance, by which every following shoot could be placed under different circumstances from its predecessor. Every leaf labored to solidify this substance during its own life; but the seed left by the flower matured only as the flower perished.

This difference in the action and endurance of the flower and leaf had been applied by nearly all great nations as a type of the variously active and productive states of life among individuals or commonwealths. Chaucer's poem of the "Flower and Leaf" is the most definite expression of the mediæval feeling in this respect, while the fables of the rape of Proserpine and of Apollo and Daphne embody that of the Greeks. There is no Greek goddess corresponding to the Flora of the Romans. Their Flora is Persephone, "the bringer of death." She plays for a little while in the Sicilian fields, gathering flowers, then snatched away by Pluto, receives her chief power as she vanishes from our sight, and is crowned in the grave. Daphne, on the other hand, is the daughter of one of the great Arcadian river gods, and of the earth; she is the type of the river mist filling the rocky vales of Arcadia; the sun, pursuing this mist from dell to dell, is Apollo pursuing Daphne; where the mist is protected from his rays by the rock shadows, the laurel and other richest vegetation spring by the river-sides, so that the laurel-leaf becomes the type, in the Greek mind, of the beneficent ministry and vitality of the rivers and the earth, under the beams of sunshine; and therefore it is chosen to form the signet-crown of highest honor for gods or men, honor for work born of the strength and dew of the earth and informed by the central light of heaven; work living, perennial, and beneficent.

J. R.

FOOTNOTES:

[Footnote 34: Read by Mr. Ruskin at the weekly evening meeting of the Royal Institution (see _Proceedings_, vol. iii., pp. 358-60), April 19, 1861.--ED.]

ON THE FORMS OF THE STRATIFIED ALPS OF SAVOY.[35]

290. The purpose of the discourse was to trace some of the influences which have produced the present external forms of the stratified mountains of Savoy, and the probable extent and results of the future operation of such influences.

The subject was arranged under three heads:--

I. The Materials of the Savoy Alps.
II. The Mode of their Formation.
III. The Mode of their subsequent Sculpture.

291. I. _Their Materials._--The investigation was limited to those Alps which consist, in whole or in part, either of Jura limestone, of Neocomian beds, or of the Hippurite limestone, and include no important masses of other formations. All these rocks are marine deposits; and the first question to be considered with respect to the development of mountains out of them is the kind of change they must undergo in being dried. Whether prolonged through vast periods of time, or hastened by heat and pressure, the drying and solidification of such rocks involved their contraction, and usually, in consequence, their being traversed throughout by minute fissures. Under certain conditions of pressure, these fissures take the aspect of slaty cleavage; under others, they become irregular cracks, dividing all the substance of the stone. If these are not filled, the rock would become a mere heap of débris, and be incapable of establishing itself in any bold form. This is provided against by a metamorphic action, which either arranges the particles of the rock, throughout, in new and more crystalline conditions, or else causes some of them to separate from the rest, to traverse the body of the rock, and arrange themselves in its fissures; thus forming a cement, usually of finer and purer substance than the rest of the stone. In either case the action tends continually to the purification and segregation of the elements of the stone. The energy of such action depends on accidental circumstances: first, on the attractions of the component elements among themselves; secondly, on every change of external temperature and relation. So that mountains are at different periods in different stages of health (so to call it) or disease. We have mountains of a languid temperament, mountains with checked circulations, mountains in nervous fevers, mountains in atrophy and decline.

292. This change in the structure of existing rocks is traceable through continuous gradations, so that a black mud or calcareous slime is imperceptibly modified into a magnificently hard and crystalline substance, inclosing nests of beryl, topaz, and sapphire, and veined with gold. But it cannot be determined how far, or in what localities, these changes are yet arrested; in the plurality of instances they are evidently yet in progress. It appears rational to suppose that as each rock approaches to its perfect type the change becomes slower; its perfection being continually neared, but never reached; its change being liable also to interruption or reversal by new geological phenomena. In the process of this change, rocks expand or contract; and, in portions, their multitudinous fissures give them a ductility or viscosity like that of glacier-ice on a larger scale. So that many formations are best to be conceived as glaciers, or frozen fields of crag, whose depth is to be measured in miles instead of fathoms, whose crevasses are filled with solvent flame, with vapor, with gelatinous flint, or with crystallizing elements of mingled natures; the whole mass changing its dimensions and flowing into new channels, though by gradations which cannot be measured, and in periods of time of which human life forms no appreciable unit.

293. II. _Formation._--Mountains are to be arranged, with respect to their structure, under two great classes--those which are cut out of the beds of which they are composed, and those which are formed by the convolution or contortion of the beds themselves. The Savoy mountains are chiefly of this latter class. When stratified formations are contorted, it is usually either by pressure from below, which raises one part of the formation above the rest, or by lateral pressure, which reduces the whole formation into a series of waves. The ascending pressure may be limited in its sphere of operation; the lateral one necessarily affects extensive tracts of country, and the eminences it produces vanish only by degrees, like the waves left in the wake of a ship. The Savoy mountains have undergone both these kinds of violence in very complex modes and at different periods, so that it becomes almost impossible to trace separately and completely the operation of any given force at a given point.

294. The speaker's intention was to have analyzed, as far as possible, the action of the forming forces in one wave of simple elevation, the Mont Salève, and in another of lateral compression, the Mont Brezon: but the investigation of the Mont Salève had presented unexpected difficulty. Its façade had been always considered to be formed by vertical beds, raised into that position during the tertiary periods; the speaker's investigations had, on the contrary, led him to conclude that the appearance of vertical beds was owing to a peculiarly sharp and distinct cleavage, at right angles with the beds, but nearly parallel to their strike, elsewhere similarly manifested in the Jurassic series of Savoy, and showing itself on the fronts of most of the precipices formed of that rock. The attention of geologists was invited to the determination of this question.

The compressed wave of the Brezon, more complex in arrangement, was more clearly defined. A section of it was given, showing the reversed position of the Hippurite limestone in the summit and lower precipices. This limestone wave was shown to be one of a great series, running parallel with the Alps, and constituting an undulatory district, chiefly composed of chalk beds, separated from the higher limestone district of the Jura and Lias by a long trench or moat, filled with members of the tertiary series--chiefly nummulite limestones and flysch. This trench might be followed from Faverges, at the head of the lake of Annecy, across Savoy. It separated Mont Vergi from the Mont Dorons, and the Dent d'Oche from the Dent du Midi; then entered Switzerland, separating the Moleson from the Diablerets; passed on through the districts of Thun and Brientz, and, dividing itself into two, caused the zigzagged form of the lake of Lucerne. The principal branch then passed between the high Sentis and the Glarnisch, and broke into confusion in the Tyrol. On the north side of this trench the chalk beds were often vertical, or cast into repeated folds, of which the escarpments were mostly turned away from the Alps; but on the south side of the trench, the Jurassic, Triassic, and Carboniferous beds, though much distorted, showed a prevailing tendency to lean towards the Alps, and turn their escarpments to the central chain.

295. Both these systems of mountains are intersected by transverse valleys, owing their origin, in the first instance, to a series of transverse curvilinear fractures, which affect the forms even of every minor ridge, and produce its principal ravines and boldest rocks, even where no distinctly excavated valleys exist. Thus, the Mont Vergi and the Aiguilles of Salouvre are only fragmentary remains of a range of horizontal beds, once continuous, but broken by this transverse system of curvilinear cleavage, and worn or weathered into separate summits.

The means of this ultimate sculpture or weathering were lastly to be considered.

* * * * *

296. III. _Sculpture._--The final reductions of mountainform are owing either to disintegration, or to the action of water, in the condition of rain, rivers, or ice, aided by frost and other circumstances of temperature and atmosphere.

All important existing forms are owing to disintegration, or the action of water. That of ice had been curiously over-rated. As an instrument of sculpture, ice is much less powerful than water; the apparently energetic effects of it being merely the exponents of disintegration. A glacier did not produce its moraine, but sustained and exposed the fragments which fell on its surface, pulverizing these by keeping them in motion, but producing very unimportant effects on the rock below; the roundings and striation produced by ice were superficial; while a torrent penetrated into every angle and cranny, undermining and wearing continually, and carrying stones, at the lowest estimate, six hundred thousand times as fast as the glacier. Had the quantity of rain which has fallen on Mont Blanc in the form of snow (and descended in the ravines as ice) fallen as rain, and descended in torrents, the ravines would have been much deeper than they are now, and the glacier may so far be considered as exercising a protective influence. But its power of carriage is unlimited, and when masses of earth or rock are once loosened, the glacier carries them away, and exposes fresh surfaces. Generally, the work of water and ice is in mountain surgery like that of lancet and sponge--one for incision, the other for ablution. No excavation by ice was possible on a large scale, any more than by a stream of honey; and its various actions, with their limitations, were only to be understood by keeping always clearly in view the great law of its motion as a viscous substance, determined by Professor James Forbes.

297. The existing forms of the Alps are, therefore, traceable chiefly to denudation as they rose from the sea, followed by more or less violent aqueous action, partly arrested during the glacial periods, while the produced diluvium was carried away into the valley of the Rhine or into the North Sea. One very important result of denudation had not yet been sufficiently regarded; namely, that when portions of a thick bed (as the Rudisten-kalk) had been entirely removed, the weight of the remaining masses, pressing unequally on the inferior beds, would, when these were soft (as the Neocomian marls), press them up into arched conditions, like those of the floors of coal-mines in what the miners called "creeps." Many anomalous positions of the beds of Spatangenkalk in the district of the Lake of Annecy were in all probability owing to this cause: they might be studied advantageously in the sloping base of the great Rochers de Lanfon, which, disintegrating in curved, nearly vertical flakes, each a thousand feet in height, were nevertheless a mere outlying remnant of the great horizontal formation of the Parmelan, and formed, like it, of very thin horizontal beds of Rudisten-kalk, imposed on shaly masses of Neocomian, modified by their pressure. More complex forms of harder rock were wrought by the streams and rains into fantastic outlines; and the transverse gorges were cut deep where they had been first traced by fault or distortion. The analysis of this aqueous action would alone require a series of discourses; but the sum of the facts was that the best and most interesting portions of the mountains were just those which were finally left, the centers and joints, as it were, of the Alpine anatomy. Immeasurable periods of time would be required to wear these away; and to all appearances, during the process of their destruction, others were rising to take their place, and forms of perhaps far more nobly organized mountain would witness the collateral progress of humanity.

J. R.

FOOTNOTES:

[Footnote 35: Read by Mr. Ruskin at the weekly evening meeting of the Royal Institution (see _Proceedings_, vol. iv., pp. 142-46), June 5, 1863.--ED.]

THE RANGE OF INTELLECTUAL CONCEPTION PROPORTIONED TO THE RANK IN ANIMATED LIFE.[36]

A THEOREM.

298. I suppose this theorem to be a truism; but I venture to state it, because it is surely desirable that it should be recognized as an axiom by metaphysicians, and practically does not seem to me yet to have been so. I say "animated life" because the word "life" by itself might have been taken to include that of vegetables; and I say "animated" instead of "spiritual" life because the Latin "anima," and pretty Italian corruption of it, "alma," involving the new idea of nourishment of the body as by the Aliment or Alms of God, seems to me to convey a better idea of the existence of conscious creatures than any derivative of "spiritus," "pneuma," or "psyche."

I attach, however, a somewhat lower sense to the word "conception" than is, I believe, usual with metaphysicians, for, as a painter, I belong to a lower rank of animated being than theirs, and can only mean by conception what I know of it. A painter never conceives anything absolutely, and is indeed incapable of conceiving anything at all, except as a phenomenon or sensation, or as the mode or locus of a phenomenon or sensation. That which is not an appearance, or a feeling, or a mode of one or the other, is to him nothing.

299. For instance, he would deny the definition of the phenomenon which he is himself first concerned in producing--a line--as "length without breadth." He would say, "That which has no breadth is nothing, and nothing cannot be long." He would define a line as a narrow and long phenomenon, and a mathematician's idea of it as an idea of the direction of such a phenomenon.

The act of conception or imagination with him, therefore, is merely the memory, simple or combined, of things that he has seen or felt. He has no ray, no incipience of faculty beyond this. No quantity of the sternest training in the school of Hegel, would ever enable him to think the Absolute. He would persist in an obstinate refusal to use the word "think" at all in a transitive sense. He would never, for instance, say, "I think the table," but "I think the table is turning," or is not, as the case might be. And if he were to be taught in any school whatever to conceive a table, his first demand would be that he should be shown one, or referred to other things that had the qualities of one in illustrative degree.

300. And even respecting the constant methods or laws of phenomena, he cannot raise the statement of them into an act of conception. The statement that two right lines can never inclose a space merely appears to him another form of verbal definition, or, at the grandest, a definition in prophetic extent, saying in other words that a line which incloses, or ever may inclose, a space, is not, and never will be, a right one. He would admit that what he now conceives as two things, doubled, would always be what he now conceives as four things. But assuming the existence of a world in which, whenever two things were actually set in juxtaposition with other two things, they became actually three times, or actually five, he supposes that the practice of arithmetic, and laws of it, would change in relation to this new condition in matter; and he accepts, therefore, the statement that twice two are four only as an accident of the existing phenomena of matter.

301. A painter therefore may, I think, be looked upon as only representing a high order of sensational creatures, incapable of any but physical ideas and impressions; and I continue my paper, therefore, only in the name of the docile, and therefore improvable, part of the Brute Creation.

And in their name I would suggest that we should be much more docile than we are if we were never occupied in efforts to conceive things above our natures. To take an instance, in a creature somewhat lower than myself. I came by surprise the other day on a cuttle-fish in a pool at low tide. On being touched with the point of my umbrella, he first filled the pool with ink, and then finding himself still touched in the darkness, lost his temper, and attacked the umbrella with much psyche or anima, hugging it tightly with all his eight arms, and making efforts, like an impetuous baby with a coral, to get it into his mouth. On my offering him a finger instead, he sucked that with two or three of his arms with an apparently malignant satisfaction, and on being shaken off, retired with an air of frantic misanthropy into the cloud of his ink.

302. Now, it seems to me not a little instructive to reflect how entirely useless such a manifestation of a superior being was to his cuttle-fish mind, and how fortunate it was for his fellow-octopods that he had no command of pens as well as ink, nor any disposition to write on the nature of umbrellas or of men.

It may be observed, further, that whatever ideas he was able to form respecting either were positively false--so contrary to truth as to be worse than none, and simply dangerous to himself, so far as he might be induced to act upon them--that, namely, an umbrella was an eatable thing, or a man a conquerable one, that the individual man who looked at him was hostile to him or that his purposes could be interfered with by ejection of ink. Every effort made by the fish under these convictions was harmful to himself; his only wisdom would have been to lie quietly and unreflectively in his pool.

And with us painters also, the only result of any efforts we make to acquaint ourselves with the subjects of metaphysical inquiry has been an increased sense of the prudence of lying placidly and unreflectively in our pools, or at least limiting ourselves to such gentle efforts of imagination as may be consistent with the as yet imperfectly developed powers, I do not say even of cephalopodic, but of Ascidian nervous centers.

303. But it may be easily imagined how pleasantly, to persons thus subdued in self-estimation, the hope presents itself which is involved in the Darwinian theory, that their pools themselves may be capable of indefinite extension, and their natures of indefinite development--the hope that our descendants may one day be ashamed of us, and debate the question of their parentage with astonishment and disgust.

And it seems to me that the aim of elementary metaphysical study might henceforth become more practical than that of any other science. For in hitherto taking little cognizance of the limitation of thought by the structure of the body, we have surely also lost sight of the power of certain modes of thought over the processes of that structure. Taking, for instance, the emotion of anger, of which the cephalopoda are indeed as capable as we are, but inferior to us in being unable to decide whether they do well to be angry or not, I do not think the chemical effect of that emotion on the particles of the blood, in decomposing and otherwise paralyzing or debilitating them, has been sufficiently examined, nor the actual quantity of nervous energy which a fit of anger of given violence withdraws from the body and restores to space, neither the correlative power of volition in restraining the passion, or in directing the choice of salutary thought, as of salutary herbs on streams. And even we painters, who dare not call ourselves capable of thought, are capable of choice in more or less salutary vision. In the degree in which we lose such power of choice in vision, so that the spectral phenomena which are the materials of our industry present themselves under forms beyond our control, we become insane; and although for all our best work a certain degree of this insanity is necessary, and the first occurring conceptions are uncommanded, as in dreams, we have, when in health, always instantaneous power of accepting some, refusing others, perfecting the outlines and colors of those we wish to keep, and arranging them in such relations as we choose.

304. And unquestionably the forms of the body which painters instinctively recognize as best, and call "beautiful," are so far under the command of the plastic force of voluntary thought, that the original and future authority of such a plastic force over the whole of creation cannot but seem to painters a direct, though not a certain influence; and they would at once give their adherence to the statement made many years since in his opening lectures in Oxford by the present Regius Professor of Medicine (as far as I can recollect approximately, in these terms)--that "it is quite as logical, and far more easy, to conceive of original anima as adapting itself to forms of substance, than of original substance as adapting to itself modes of mind."

305. It is surely, therefore, not too much to expect of future schools of metaphysicians that they will direct mankind into methods of thought which will be at once happy, unerring, and medicinal, and therefore entirely wise; that they will mark the limits beyond which uniformity must be dangerous, and speculation vain; and that they will at no distant period terminate the acrimony of theologians, and the insolences, as well as the sorrows, of groundless faith, by showing that it is appointed for us, in common with the rest of the animal creation, to live in the midst of an universe the nature of which is as much better than we can believe, as it is greater than we can understand.

FOOTNOTES:

[Footnote 36: Contemporary Review, June, 1871.--ED.]

* * * * *

LITERATURE.

FICTION--FAIR AND FOUL.

(_Nineteenth Century, June, August, Sept., Nov. 1880, and Oct. 1881._)

FAIRY STORIES.

(_Preface to "German Popular Stories," 1868._)

* * * * *

FICTION, FAIR AND FOUL.

1.[37]

1. On the first mild--or, at least, the first bright--day of March, in this year, I walked through what was once a country lane, between the hostelry of the Half-moon at the bottom of Herne Hill, and the secluded College of Dulwich.