Chapter XII: Part 12

Having thus glanced at some of the coal mines of Great Britain, we now pass to some of those of the United States. In these coal is found in _four_ different forms: _first_, the _genuine_ anthracite, or _glance_ coal, as near Worcester, Mass., and Newport, R. I.; _second_, coal destitute of bitumen, commonly called anthracite, but which is more properly anasphaltic, which is found at Pottsville, Mauch Chunk, Lackawanna, Wilkesbarre, &c.; _third_, bituminous coal, usually found in the slate rock, as at Tioga, Lycoming, etc.; and _fourth_, the lignite coal, found along the south shore of the bay of South Amboy, New Jersey. From the state of Alabama to Pictou, Nova Scotia, the coal beds can be followed in a north-east direction, for fifteen hundred miles; and from Richmond, in Virginia, to Rock River, in Illinois, they are continually crossed at right angles, for about eight hundred miles. At Richmond, the coal is bituminous; on the Alleghany belt, it is anthracite. Geologists think that the anthracite was lifted out of its horizontal position when the great Alleghany belt was upheaved, and that its non-bituminous quality is owing to the influence of the intense heat that accompanied its upheaval.

Taylor, in his book on coal, estimates the area of bituminous coal in the United States, east of the Mississippi river, at one hundred and twenty-four thousand, seven hundred and thirty-five square miles, and west of the Mississippi, at eight thousand, three hundred and ninety-seven square miles; British North America, eighteen thousand square miles bituminous. More than one-third of the area of Pennsylvania, is more or less marked by coal formations; one-third of Kentucky, Ohio and Virginia, one-fifth of Indiana, and three-fourths of Illinois, are occupied by carboniferous strata. Western Pennsylvania abounds in bituminous coal, and it is found also in several counties of New York. By the census of 1839-40, we find that the quantity of bituminous coal produced that year in the United States, was twenty-seven million, six hundred and three thousand, one hundred and ninety-one bushels, employing about four thousand men, and a capital of some two million dollars; and that about four million dollars of capital were invested in raising anthracite coal, of which some nine hundred thousand tuns (of about twenty-eight bushels each) were produced by the labors of about three thousand men. Most of this was from Pennsylvania.

In 1819, the anthracite coal trade had no existence; in 1820, this kind of coal was first used as fuel, and just three hundred and sixty-five tuns were sent to market; in 1845, the amount was two million tuns; in 1850, about three million, five hundred thousand tuns, and the present year (1854) the amount will probably be between six and seven million tuns. The demand and supply so steadily and rapidly increase that it is impossible to estimate the vast extent the business of coal mining is yet to attain.

Glancing for a moment at other countries, we find that Belgium, in 1845, had two hundred and twelve mines, employing thirty-eight thousand miners and five hundred steam-engines, and producing five million tuns; France, four hundred and forty-nine mines, employing thirty thousand miners, and producing five million tuns; Prussia, in 1840, seven hundred and fifty-two mines, employing twenty-four thousand miners, and raising three million, five hundred thousand tuns; and that Great Britain, in 1846, produced thirty-five million tuns, valued at forty-five million dollars at the mines. Austria and Spain, also, have excellent mines, though less productive. And as a late and interesting discovery, it may be added, that the recent Arctic expedition sent out from England, found coal in those northern regions, on the island of Disco, outcropping near the shore. They also, in another locality not far off, discovered some curious specimens of petrified trees, and near them extensive quarries of anthracite coal, of good quality. There appeared to be no limit to the quantity that might be thrown into a boat with ease, and in the space of three hours they conveyed not less than twelve tuns to the steamer, three-quarters of a mile distant. It proved, on trial, to be of good quality, the combustion was perfect, and the coal as economical as the Welsh.

We will conclude the subject of coal mines, with the statement of a recent tourist, as to some of the wonders of the Cornish mines in England, as he saw them in 1854. He says: “Some of the mines are truly grand undertakings. The ‘consolidated mines,’ the largest of the Cornish group, employ upward of three thousand persons. One of the engines pumps water from a direct depth of sixteen hundred feet, the weight of the pumping apparatus alone being upward of five hundred tuns; the pumping-rod is one thousand, seven hundred and forty feet long, and it raises about two million gallons of water in a week, from a depth equal to five times the hight of St. Paul’s. These are, indeed, wonders to marvel at! The consolidated and united mines, both belonging to one company, are stated to have used the following vast quantities of materials in a year: coals, fifteen thousand, two hundred and seventy tuns; candles, one hundred and thirty-two thousand, one hundred and forty-four pounds; gunpowder, eighty-two thousand pounds; leather, for straps, &c., thirteen thousand, four hundred and ninety-three pounds; pick and shovel handles, sixteen thousand, six hundred and ninety-eight dozens. Sir Charles Lemon has estimated, that in the whole of the Cornish mines, thirteen thousand pounds’ worth of gunpowder is used annually; that the timber employed in the underground works, equals the growth of one hundred and forty square miles of Norwegian forest; and that thirty-seven million tuns of water are raised annually from the mines.”

SALT MINES.

Hence with diffusive salt old Ocean steeps,
His emerald shallows, and his sapphire deeps.
Oft in wide lakes, around their warmer brim,
In hollow pyramids the crystals swim;
Or, fused by earth-born fires, in cubic blocks
Shoot their wide forms, and harden into rocks.—DARWIN.

Culinary salt, or, as it is termed in chemistry, muriate of soda, exists abundantly in a native state, both in a solid form, and dissolved in water. It occurs, in solution, not only throughout the wide range of the ocean, but in various springs, rivers and lakes; and is known, in its solid form, as a peculiar mineral, under the names of _rock-salt_, _fossil salt_, and _salt-gem_. Its beds are mostly beneath the surface of the ground, but sometimes rise into hills of considerable elevation. At Cordova, in Spain, a hill, between four and five hundred feet in hight, is nearly composed of this mineral. But the most celebrated salt mines are those of Wielicza, in Gallicia, commonly called the salt mines of Cracow, those of Tyrol, of Castile, (in Spain,) and of Cheshire, in England. In the province of Lahore, in Hindoostan, is a hill of rock-salt, of equal magnitude with that near Cordova. The mines of Iletski, in Russia, yield vast quantities of this substance. It is so plentiful in the desert of Caramania, and the air so dry, that it is there used as a material for building. It forms the surface of a large part of the northern desert of Lybia; and is found in great abundance in the mountains of Peru. It has a pure saline taste, without any mixture of bitterness; and crystallizes in cubes when obtained by slow evaporation from its solution. In Germany the mines of this kind are numerous: one of the largest is that of Hallein, near Saltzburg, in which the salt is hewn out from subterraneous caverns of a considerable range, and exhibits almost every diversity of color, as yellow, red, blue and white; in consequence of which it is dissolved in water, to be liberated from its impurities, and afterward recrystallized. The salt mines of Cracow, and those of Cheshire, merit a particular description.

SALT MINES OF CRACOW.

Thus, cavern’d round, in Cracow’s mighty mines,
With crystal walls a gorgeous city shines;
Scoop’d in the briny rock long streets extend
Their hoary course, and glittering domes ascend:
Down their bright steeps, emerging into day,
Impetuous fountains burst their headlong way,
O’er milk-white vales in ivory channels spread,
And wondering seek their subterraneous bed.
Form’d in pellucid salt, with chisel nice,
The pale lamp glittering through the sculptur’d ice,
With wild reverted eyes fair Lotta stands,
And spreads to heaven, in vain, her glassy hands;
Cold dews condense upon her pearly breast,
And the big tear rolls lucid down her vest.
Far gleaming o’er the town, transparent fanes
Rear their white towers, and wave their golden vanes:
Long lines of lusters pour their trembling rays,
And the bright vault resounds with mingled blaze.—DARWIN.

These celebrated excavations are about five miles distant from the city of Cracow, in a small town named Wielicza, which is entirely undermined, the cavities reaching to a considerable extent beyond its limits. The length of the great mine, a view of which is seen on the next page, from east to west, is six thousand feet; its breadth, from north to south, two thousand; and its greatest depth eight hundred; but the veins of salt are not limited to this extent, the depth and length of them, from east to west, being yet unknown, and their breadth only, hitherto determined. There are at present ten shafts; and not a single spring has been discovered throughout the extent of the mine.

In descending to the bottom, the visitor is surprised to find a kind of subterraneous commonwealth, consisting of many families, who have their peculiar laws and polity. Here are likewise public roads and carriages, horses being employed to draw the salt to the mouths of the mine, where it is taken up by engines. These horses, when once arrived at their destination, never more see the light of the sun; and many of the people seem buried alive in this strange abyss, having been born there, and never stirring out; while others are not denied frequent opportunities of breathing the fresh air in the fields, and enjoying the surrounding prospects. The subterraneous passages, or galleries, are very spacious, and in many of them chapels are hewn out of the rock-salt. In these passages crucifixes are set up, together with the images of saints, before which a light is kept constantly burning. The places where the salt is hewn out, and the empty cavities whence it has been removed, are called chambers, in several of which, where the water has stagnated, the bottoms and sides are covered with very thick incrustations of thousands of salt crystals, lying one on the other, and many of them weighing half a pound and upward. When candles are placed before them, the numerous rays of light reflected by these crystals emit a surprising luster.

In several parts of the mine, huge columns of salt are left standing, to support the rock; and these are very fancifully ornamented. But the most curious object in the inhabited part, or subterraneous town, is a statue which is considered by the immured inhabitants as the actual transmutation of Lot’s wife into a pillar of salt; and in proportion as this statue appears either dry or moist, the state of the weather above ground is inferred. The windings in this mine are so numerous and intricate, that the workmen have frequently lost their way; and several, whose lights have been extinguished, have thus perished. The number of miners to whom it gives employment, is computed at between four and five hundred; but the whole amount of the men employed in it is about seven hundred.

The salt lies near the surface, in large, shapeless masses, from which blocks of sixty, eighty, or a hundred feet square, may be hewn; but at a considerable depth it is found in smaller lumps. About six hundred thousand quintals of salt are dug annually out of the mines of Cracow. The worst and cheapest is called green salt, from its greenish color, occasioned by a heterogenous mixture of a grayish mineral, or clay, and entirely consists of salt crystals of different dimensions. A finer sort is dug out in large blocks; and the third kind is the _sal gemmæ_, or crystal salt, which is found in small pieces interspersed in the rock, and, when detached from it, breaks into cubes of rectangular prisms. This is usually sold unprepared. The color of the salt stone is a dark gray mixed with yellow.

SALT MINES AND SPRINGS OF CHESHIRE, ENGLAND.

The Cheshire rock-salt, with very few exceptions, has hitherto been ascertained to exist only in the valleys bordering on the river Weaver and its tributary streams; in some places manifesting its presence by springs impregnated with salt, and in others being known by mines actually carried down into the substance of the salt strata. Between the source of the Weaver and Nantwich, many brine springs make their appearance; and occur again at several places, in proceeding down the stream. At Moulton, a mine has been sunk into the body of rock-salt, and a similar mine is wrought near Middlewich. At Northwich, brine springs are very abundant; and there also many mines have been sunk for the purpose of working out the fossil salt. In that vicinity a body of rock-salt has been met with in searching for coal.

The brines in this district are formed by the penetration of spring or rain waters to the upper surface of the rock-salt, in passing over which they acquire such a degree of strength, that one hundred parts have yielded twenty-seven of pure salt, thus nearly approaching to the perfect saturation of brine. Their strength is therefore much greater than that of the salt springs met with in Hungary, Germany and France. The brine having been pumped out of the pits, is first conveyed into large reservoirs, and afterward drawn off as it is needed, into pans made of wrought iron. Here heat is applied in a degree determined by the nature of the salt to be manufactured, and various additions are made to the brine, with a view either to assist the crystallization of the salt, or to promote the separation of the earthy particles, which exist in a very small proportion. The importance of the manufacture of Cheshire salt will be sufficiently obvious from the statement, that, besides the salt made for home consumption, the annual amount of which has exceeded sixteen thousand tuns, the average of the quantity sent yearly to Liverpool for exportation, has not been less than one hundred and forty thousand tuns.

The mine of rock-salt first worked was discovered by accident at Marbury, near Northwich about a century and a half ago; and this bed had been wrought for more than a century, when, in the same neighborhood, a second and inferior stratum was fallen in with, separated from the former by a bed of indurated clay. This lower stratum was ascertained to possess a very great degree of purity, and freedom from earthy admixture; on which account, and from the local advantages of Northwich for exportation, the fossil salt is worked in the vicinity of that place only. It occurs in two great strata or beds, lying nearly horizontally, and separated, the superincumbent from the subjacent stratum, by several layers of indurated clay, or argillaceous stone. These intervening beds possess, in conjunction, a very uniform thickness of from thirty to thirty-five feet, and are irregularly penetrated by veins of fossil salt. There is every reason to believe that the beds of rock-salt at Northwich, are perfectly distinct from any others in the salt district, and form what are termed by mineralogists _incumbent bodies_ or _masses of mineral_.

These enormous masses stretch a mile and a half in a longitudinal direction from north-east to south-west; but their transverse extent, as measured by a line at right angles from the former, does not exceed forty-two hundred feet, somewhat more than three-quarters of a mile. Without this area, the brine which is met with, is of a very weak and inferior quality, and at a short distance disappears altogether. The thickness of the upper bed varies from sixty to ninety feet; and a general estimate made from its level, shows that its upper surface, which is ninety feet beneath that of the earth, is at least thirty-six feet beneath the low-water mark of the sea at Liverpool; a fact not unimportant in determining the nature of the formation of this mineral. The thickness of the lower bed has not hitherto been ascertained; but the workings are usually begun at the depth of from sixty to seventy-five feet, and are carried down for the space of fifteen or eighteen feet, through what forms the purest portion of the bed. In one of the mines a shaft has been sunk to a level of forty-two feet still lower, without passing through the body of rock-salt. There is thus an ascertained thickness of this bed of about a hundred and twenty feet, and without any direct evidence that it may not extend to a considerably greater depth.

Although two distinct beds, only, of fossil salt have been met with at Northwich, it has been ascertained that the same limitations do not exist throughout the whole of the salt district. At Lawton, near the source of the river Wheelock, three distinct beds have been found, separated by strata of indurated clay: one at the depth of one hundred and twenty-six feet, four feet in thickness; a second, thirty feet lower, twelve feet in thickness; and a third, forty-five feet further down, which was sunk into seventy-two feet, without passing through its substance. The intervening clay, the structure of which is very peculiar, is called the shaggy metal, and the fresh water which passes through its pores has the expressive appellation of Roaring Meg. This epithet will not appear too strong, when it is mentioned that in a mine in which the section of strata was taken, and where the “shaggy metal” was found at the depth of about eighty feet, the quantity of water ascertained to issue from its pores in one minute, was not less than three hundred and sixty gallons; a circumstance which greatly enhances the difficulty of passing a shaft down to the body of rock-salt.

In many of these beds of argillaceous stone, a portion of salt, sufficiently strong to affect the taste, is found to exist; and this saltness increases, as might be expected, in proportion as the body of rock-salt is approached. In the strata or layers immediately above the rock, which in all the mines are perfectly uniform in their appearance and structure, this is particularly remarkable, notwithstanding there are not, in these strata, any veins of rock-salt connected with the great mass below. On the contrary, the line between the clay and rock-salt is drawn with great distinctness in every instance, without presenting any of those inequalities which would arise from a mutual penetration of the strata. Not any marine exuviæ, or organic remains, are found in the strata above the rock-salt; and the almost universal occurrence of gypsum, in connection with beds of fossil salt, is a fact still more deserving of observation, because it appears, not only in these mines, but also in the salt mines of Hungary, Poland and Transylvania; on which account Werner, in his geognostic system, assigns to the rock-salt and fletz gypsum a conjunct situation.

The fossil salt extracted from the Northwich mines is of different degrees of purity, and more or less blended with earthy and metallic substances. The purer portion of the lower bed yields a rock-salt, which, being principally exported to the Baltic, obtains the name of Prussian rock. The extent of the cavity formed by the workings, varies in different mines, the average depth being about sixteen feet. In some of the pits, where pillars from eighteen to twenty-four feet square form the supports of the mine, the appearance of the cavity is singularly striking, and the brilliancy of the effect is greatly increased when the mine is illuminated by candles fixed to the sides of the rock. The scene thus formed almost appears to realize the magic palaces of eastern poets. Some of the pits are worked in aisles or streets, but the choice here is wholly arbitrary. Among the methods employed in working out the rock-salt, the operation of blasting is applied to the separation of large masses from the body of the rock, and these are afterward broken down by the mechanical implements in common use. The present number of mines is eleven or twelve, from which there are raised, on an annual average, fifty or sixty thousand tuns of rock-salt. The greater part of this quantity is exported to Ireland and the Baltic, the remainder being employed in the Cheshire district, in the manufacture of white salt, by solution and subsequent evaporation.

The general situation occupied by the rock-salt in Cheshire is very similar to that of the Transylvanian and Polish mines, the beds of this mineral being disposed in small plains, bounded by hills of inconsiderable hight, forming a kind of basin or hollow, from which there is usually only a narrow egress for the waters. The situation of the Austrian salt mines near Saltzburg is, however, very different. The mineral there appears to be disposed in beds of great thickness, which occur near the summits of limestone hills, at a great elevation above the adjoining country. This is a singular fact; and if the hypothesis be allowed that rock-salt is formed from the waters of the sea, it is necessary to suppose the occurrence on this spot of the most vast and surprising changes!

Though there are no salt _mines_ in the United States, there are salt _springs_ in several places. By far the most important and valuable of these, are in the neighborhood of Syracuse, in the state of New York. The land containing these springs, is owned by the state, and is leased free of rent, to be used only for the manufacture of salt. The wells are dug, and the water pumped up at the expense of the state, and the manufacturer pays a duty of one cent on each bushel he makes. Some of the wells are sunk to the depth of four hundred feet. Fine salt is prepared by boiling; and coarse by solar evaporation. In 1850, the number of salt manufactories in this vicinity was one hundred and ninety-two; and the quantity of salt produced in 1853, amounted to more than five million bushels. The salt of this region has been thoroughly tested, and found to be fully equal to any of foreign manufacture.

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PHENOMENA OF THE OCEAN.

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“They that go down to the sea in ships, that do business in great
waters; these see the works of the Lord, and his wonders in the
deep.”—PSALMS.

“With wonder mark the moving wilderness of waves,
From pole to pole through boundless space diffused,
Magnificently dreadful! where, at large,
Leviathan, with each inferior name
Of sea-born kinds, ten thousand thousand tribes,
Find endless range for pasture and for sport.
Adoring own
The Hand Almighty, who in channeled bed
Immeasurable sunk, and poured abroad,
Fenced with eternal mounds, the fluid sphere;
With every wind to waft large commerce on.
Join pole to pole, consociate severed worlds,
And link in bonds of intercourse and love
Earth’s universal family.”—MALLET.

That huge mass of waters impregnated with salt, which encompasses all parts of the globe, and by the means of which, in the present improved state of navigation, an easy intercourse subsists between the most distant nations, is denominated the ocean, and has three grand divisions assigned to it. First, that vast expanse of water which lies to the westward of the northern and southern continents of America, and by which those continents are divided from Asia. On account of the uniform and temperate gales which sweep its surface within the tropics, it is named the Pacific ocean; and has again been distinguished into the northern and southern Pacific, (the equator being considered as the dividing line,) and the Southern ocean, or South sea, being consequently that part of the general assemblage of waters which is contained between the fortieth degree of south latitude and the south pole. Its general width is estimated at about ten thousand miles. Secondly, the Atlantic ocean, which divides Europe and Africa from the two American continents, and has a general width of about three thousand miles; while the waters which occupy the polar regions are named the Northern sea. And, lastly, the Indian ocean, which extends from the eastern shores of Africa along the southern coasts of Asia, and has the same general width with the preceding one.

Among the chief of those less expansive sheets of water, properly called seas, may be mentioned the Baltic, the Mediterranean sea, and the Black and Red seas. The Caspian sea, being entirely encompassed by land, might, with more propriety, have been styled a lake; but as its water possesses the quality of saltness, it is ranked among the seas. It is, notwithstanding, certain that Lake Superior has a still greater circumference, extending around its shores at least fourteen hundred miles, while the extent of the Caspian does not exceed twelve hundred.

Of the origin of this division into different seas, and seas of different depths, little is known; but it is highly probable that many of the larger excavations and partitions now met with, have existed, without much change as to their extent, from the creation. Others have undoubtedly been the result of that conflict which is perpetually taking place between the elements of land and water, and which has, for the greater part, given rise to islands, isthmuses and peninsulas; while subterraneous volcanoes, and the truly surprising and indefatigable exertions of coral, madrepores, tubipores, and other restless and multitudinous zoöphytes, have laid, and are daily laying, the foundation of new islands and continents in the middle of the widest and deepest seas.

The quantity of water in the ocean, not only remains constantly the same, but, notwithstanding its most violent and incessant motion, continues stable within certain limits. This, however, can not be inferred from observation; for, although in the almost infinite variety of disturbances to which the ocean is liable, from the action of irregular causes, it may appear to return to its former state of equilibrium, still it may be apprehended that some extraordinary cause may communicate to it a shock, which, though inconsiderable at first, may augment continually, and elevate it above the highest mountains. It is, therefore, interesting to investigate the conditions which are necessary for the absolute stability of the ocean. This has been effected by the celebrated Laplace, who has demonstrated that the equilibrium of the ocean _must_ be stable, if the density be _less_ than the mean density of the earth, which is known to be the case. He has likewise determined, by means of his refined analysis, that this stability would cease to exist, if the mean density of the sea _were to exceed_ that of the earth; so that the stability of the equilibrium of the ocean, and the excess of the density of the terrestrial globe above that of the waters which cover it, are reciprocally connected with each other, and indicate infinite wisdom and contrivance in such an adjustment.

SALTNESS OF THE SEA.

Of the various phenomena of the sea, that of its _saltness_ is one of the most obvious. No questions concerning the natural history of our globe have been discussed with more attention, or decided with less satisfaction, than that concerning its primary cause, which had perplexed the philosophers before the time of Aristotle, and surpassed even the great genius of that profound inquirer into natural causes. Kircher, after having consulted not less than thirty-three authors on this subject, could not help remarking, that the fluctuations of the ocean itself were scarcely more various than the opinions concerning the origin of its saline impregnation.

This question does not seem capable of admitting an illustration from experiment; at least, not from any experiments hitherto made for that purpose: it is, therefore, not surprising, that it remains nearly as problematical in the present age, as it has been in any of the preceding. Had observations been made three or four centuries ago, to ascertain the saltness of the sea, then, at any particular time and place, we might now, by making similar observations at the same place, in the same season, have been able to know, whether the saltness, at that particular place, was increasing or decreasing, or an invariable quantity. This kind and degree of knowledge would have served as a clue to direct us to a full investigation of this matter in general. It is to be regretted, however, that observations of this nature have not, in former days, been made with any degree of precision.

One of the principal opinions maintained on this subject by modern philosophers, and more particularly supported by Halley, is, that since river-water, in almost every part of the globe, is impregnated in a greater or less degree by sea-salt, the sea must have gradually acquired its present quantity of salt from the long continued influx of rivers. The water which is carried into the sea by these rivers, is again separated from it by evaporation, and being dispersed over the atmosphere by winds, soon descends in rain or vapor upon the surface of the earth, whence it hastens to pour into the bosom of the ocean the fresh tribute of salt it has collected in its inland progress. Thus the salt conveyed into the sea not being a volatile substance, nor performing an incessant circulation, must be a perpetually increasing quantity; and sufficient time, it is contended, has elapsed since the creation, for the sea to acquire, from this source, its present quantity of salt.

This opinion has been successfully combated; and it is denied that freshwater rivers could, in the course of thousands or even millions of years, have produced saltness in the sea. If this were the case, every sea, or great body of water, which receives rivers, must have been salt, and have possessed a degree of saltness in proportion to the quantity of water which these rivers discharge. But so far is this from being true, that the Palus Mæotis, and our great American lakes, do not contain salt water, but fresh. It may indeed be objected, that the quantity of salt which rivers carry along with them, and deposit in the sea, must depend on the nature of the soil through which they flow, which may in some places not contain any salt; and that this is the reason why the great lakes in America and the Palus Mæotis are fresh. But to this opinion, which is merely hypothetical, there are insurmountable objections. It is a curious fact, that the saltness of the sea is greatest under the equator, and diminishes gradually toward the poles; but it can not therefore be assumed that the earth contains more salt in the tropical regions than in the temperate zones, and more in these again than in the frigid zones. On the other hand, if it be allowed that the sea receives its saltness from the rivers, it must be equally salt, or nearly so, in every part of the earth; since, according to a simple and well-known principle in chemistry, _when any substance is dissolved in water with the assistance of agitation, at whatever part of the water it is introduced, it will be equally diffused through the whole liquid_. Now, though it were true that a greater quantity of salt should have been introduced into the sea under the equator, than toward the poles, from the constant agitation occasioned by the wind and tide, the salt must have soon pervaded the whole mass of water. Neither is this greater proportion of saltness owing to a superior degree of heat, since it is an established principle in chemistry, that cold water and hot water dissolve nearly the same proportion of salt.

The saltness of the sea has also been ascribed to the solution of subterraneous mines of salt, that are supposed to abound in the bottom of the sea, and along its shores. But this hypothesis can not be supported. If the sea were constantly dissolving salt, it would soon become saturated; for it can not be said that it is deprived of any portion of its salt by evaporation, since rain-water is fresh. If the sea were to become saturated, neither fishes nor vegetables could live in it. It may hence be inferred that the saltness of the sea can not be accounted for by secondary causes, and _that it has been salt since the beginning of time_. It is indeed impossible to suppose that the waters of the sea were at any time fresh since the formation of fishes and sea-plants; neither will they live in water which is fresh. It may hence be concluded that the saltness of the sea has, with some few exceptions, perhaps arising from mines of rock-salt dispersed near its shores, been nearly the same in all ages. This hypothesis, which is the simplest, and is involved in the fewest difficulties, best explains the various phenomena dependent on the saltness of the sea.

Although this saline property may be one of the causes by which the waters of the sea are preserved from putridity, still it can not be considered as the principal cause. The ocean has, like rivers, its currents, by which its contents are circulated round the globe; and these may be said to be the great agents which keep it sweet and wholesome. A very enlightened navigator, Sir John Hawkins, speaks of a calm, in which the sea, having continued for some time without motion, assumed a very formidable aspect. “Were it not,” he observes, “for the moving of the sea by the force of winds, tides and currents, it would corrupt all the world. The experiment of this I saw in the year 1590, lying with a fleet about the islands of the Azores, almost six months, the greater part of which time we were becalmed. Upon which, all the sea became so replenished with various sorts of gellies, and forms of serpents, adders and snakes, as seemed wonderful; some green, some black, some yellow, some white, some of divers colors, and many of them had life; and some there were a yard and a half, and two yards long; which, had I not seen, I could hardly have believed. And hereof are witnesses all the companies of the ships which were then present; so that hardly a man could draw a bucket of water clear of some corruption. In which voyage, toward the end thereof, many of every ship fell sick, and began to die apace. But the speedy passage into our country, was a remedy to the diseased, and a preservative to those who were not touched.”

CONGELATION OF SEA-WATER.

Although the assertion that salt water never freezes, has been contradicted by repeated experience, it is still certain that it requires a much greater degree of cold to produce its congelation, than fresh water. It is, therefore, one of the greatest blessings which we derive from this element, that when we find all the stores of nature locked up to us on the land, the sea is, with few exceptions, ever open to our necessities. It is well known that at particular seasons, the mouth of the river St. Lawrence, the entrance into the Baltic sea, &c., are so much frozen over as to be impassable by ships; while the vast mountains and fields of ice in the polar regions, have for ages past been insurmountable obstructions to the daring researches of modern navigators. These exceptions, however, will appear of comparatively trifling importance to navigation, when the number of ports which are, in almost every region, open at all seasons of the year, are considered; and this facility of intercourse would certainly not have been afforded, if sea-water had admitted of as easy a congelation as that of water not impregnated with salt.

On the origin of ice in the frozen seas, different opinions have been entertained. The authority of Capt. Cook and Lord Mulgrave, has been cited by Bishop Watson, to show that good fresh water may be procured from ice found in those seas; but he observes that, notwithstanding the testimonies of these very able navigators, it may still be doubted whether the ice from which the water was obtained, had been formed in the sea, and, consequently, whether sea-water itself would, when frozen, yield fresh water. He thinks it probable that the ice had either been formed at the mouths of large fresh-water rivers, and had thence, by tides or torrents been drifted into the sea, or that it had been broken by its own weight, from the immense cliffs of ice and frozen snow which, in countries where there are few rivers, are found in high latitudes to project a great way into the sea. An early navigator, Fotherbye, in the relation of his voyage toward the south pole, in 1614, considers snow to be the original cause of the ice found at sea, he himself having observed it to lie an inch thick on the surface; and Captain Cook, from his own observation in the South sea, was disposed to think that the vast floats of ice he met with in the spring, were formed from the congelation of snow. It is certain that the snow which falls upon the surface of the sea, being in a solid state, and, bulk for bulk, lighter than sea-water, will not readily combine with it, but may, by a due degree of cold in the atmosphere, be speedily converted into a layer of ice. The upper layer of this first surface of ice being elevated above the surface of the sea, will receive all the fresh water which falls from the atmosphere in the form of snow, sleet, rain or dew, by the successive congelation of which, the largest fields of ice may at length be formed.

It is a matter of little consequence to a navigator, whence the ice which supplies him with fresh water is produced. Leaving, therefore, these hypotheses relative to the formation of ice in frozen seas, it should be observed that the question, whether congealed sea-water will, when thawed, yield fresh water, has been satisfactorily decided by experiments made with every suitable attention. A quantity of sea-water having been taken up off the English coast, was exposed to a freezing atmosphere, and afforded an ice perfectly free from any taste of salt; and it has likewise been found, that not only sea-water, but water containing double the proportion of salt commonly found in our sea-water, and more than is contained in the sea-water of any climate, may be frozen by the cold prevailing in our atmosphere.

ICE-ISLANDS.

Ice-islands, or icebergs, as they are commonly called, is the name given by seamen to the huge, solid masses of ice which abound in the sea near or within the polar circles, and which often float down nearer to the equator, till they are gradually dissolved by the increasing warmth of the air and water. The cut gives a view of them as seen by Dr. Scoresby, who counted five hundred of them between latitude sixty-nine degrees and seventy degrees north, which were from one hundred to two hundred feet high, and from a few yards to a mile in circumference. Many of these fluctuating islands are met with on the coasts of Spitzbergen, to the great danger of the vessels employed in the Greenland fishery. In the midst of these tremendous masses, navigators have been arrested and frozen to death. In this manner the brave Sir Hugh Willoughby perished, with all his crew, in 1553; and in the year 1773, Lord Mulgrave, after every effort which the most accomplished seaman could make, to reach the termination of his voyage, was caught in the ice, and nearly experienced the same unhappy fate. The scene he describes, divested of the horrors attendant on the eventful expectation of change, was most beautiful and picturesque. Two large ships becalmed in a vast basin, surrounded on all sides by ice-islands of various forms; the weather clear; the sun gilding the circumambient ice, which was smooth, low, even, and covered with snow, except where pools of water, on a portion of the surface, shot forth new icy crystals, and on the smooth surface of the comparatively small space of sea in which they were hemmed. Such is the picture drawn by our navigator, amid the perils by which lie was surrounded.

After fruitless attempts to force their way through the fields of ice, the limits of these became at length so contracted, that the ships were immovably fixed. The smooth extent of surface was soon lost; the pressure of the pieces of ice, by the violence of the swell, caused them to pack; and fragment rose upon fragment, until they were in many places higher than the main-yard. The movements of the ships were tremendous and involuntary, in conjunction with the surrounding ice, actuated by the currents. The water having shoaled to fourteen fathoms, great apprehensions were entertained, as the grounding of the ice, or of the ships, would have been equally fatal: the force of the ice might have crushed them to atoms, or have lifted them out of the water, and have overset them; or, again, have left them suspended on the summits of the pieces of ice, at a tremendous hight, exposed to the fury of the winds, or to the risk of being dashed to pieces by the failure of their frozen dock. An attempt was made to cut a passage through the ice; but after a perseverance truly worthy of Britons, it proved ineffectual. The commander, who was at all times master of himself, directed the boats to be made ready to be hauled over the ice, till they should reach navigable water, proposing in them to make the voyage to England; but after they had thus been drawn over the ice, for three progressive days, a wind having sprung up, the ice separated sufficiently to yield to the pressure of the ships in full sail. After having labored against the resisting fields of ice, they at length reached the harbor of Smeerinberg, at the west end of Spitzbergen.

The vast islands of floating ice which abound in the high southern latitudes, are a proof that they are visited by a much severer degree of cold than equal latitudes toward the north pole. Captain Cook, in his second voyage, fell in with one of these islands in latitude fifty degrees, forty minutes, south. It was about fifty feet high, and half a mile in circuit, being flat on the top, while its sides, against which the sea broke exceedingly high, rose in a perpendicular direction. In the afternoon of the same day, the tenth of December, 1773, he fell in with another large cubical mass of ice, about two thousand feet in length, four hundred feet in breadth, and in hight two hundred feet. Mr. Foster, the naturalist of the voyage, remarks that, according to the experiments of Boyle and Marian, the volume of ice is to that of sea-water as ten to nine: consequently, by the known rules of hydrostatics, the volume of ice which rises above the surface of the water, is to that which sinks below it as one to nine. Supposing, therefore, this mass of ice to have been of a regular figure, its depth under water must have been eighteen hundred feet, and its whole hight, twenty hundred feet: estimating its length, as above, at twenty hundred feet, and its breadth at four hundred feet, the entire mass must have contained sixteen hundred millions of cubic feet of ice.

Two days after, several other ice-islands were seen, some of them nearly two miles in circuit, and six hundred feet high; and yet such was the force of the waves, that the sea broke quite over them. They exhibited for a few moments a view very pleasing to the eye; but a sense of danger soon filled the mind with horror; for had the ship struck against the weather-side of one of these islands, when the sea ran high, she must in an instant have been dashed to pieces. The route to the southward was afterward impeded by an immense field of low ice, the termination of which could not be seen, either to the east, west or south. In different parts of this field were islands, or hills of ice, like those which had before been found floating in the sea.

At length these ice-islands became as familiar to those on board as the clouds and the sea. Whenever a strong reflection of white was seen on the skirts of the sky, near the horizon, then ice was sure to be encountered; notwithstanding which, that substance itself was not entirely white, but often tinged, especially near the surface of the sea, with a most beautiful sapphirine, or rather berylline blue, evidently reflected from the water. This blue color sometimes appeared twenty or thirty feet above the surface, and was probably produced by particles of sea-water which had been dashed against the mass in tempestuous weather, and had penetrated into its interstices. In the evening, the sun setting just behind one of these masses, tinged its edges with gold, and reflected on the entire mass a beautiful suffusion of purple. In the larger masses, were frequently observed shades or casts of white, lying above each other in strata, sometimes of six inches, and at other times of a foot in hight. This appearance seemed to confirm the opinion entertained relative to the increase and accumulation of such huge masses of ice, by heavy falls of snow at different intervals; for snow being of various kinds, small-grained, large-grained, in light feathery locks, &c., the various degrees of its compactness may account for the different colors of the strata.

In his third attempt to proceed southward, in January, 1774, Capt. Cook was led, by the mildest sunshine which was, perhaps, ever experienced in the frigid zone, to entertain hopes of penetrating as far toward the south pole as other navigators have done toward the north pole; but on the twenty-sixth of that month, at four in the morning, his officers discovered a solid ice-field of immense extent before them, bearing from east to west. A bed of fragments floated around this field, which was raised several feet above the surface of the water. While in this situation, the southern part of the horizon was illuminated by the rays of light reflected from the ice, to a considerable hight. Ninety-seven ice-islands were distinctly seen within the field, besides those on the outside; many of them very large, and looking like a ridge of mountains, rising one above the other until they were lost in the clouds. The most elevated and most ragged of these ice-islands, were surmounted by peaks, and were from two to three hundred feet in hight, with perpendicular cliffs or sides astonishing to behold. The largest of them terminated in a peak not unlike the cupola of St. Paul’s.

The outer, or northern edge of this immense field of ice, was composed of loose or broken ice, closely packed together, so that it was not possible to find any entrance. Such mountains of ice, Captain Cook was persuaded, were never seen in the Greenland seas, so that no comparison could be drawn; and it was the opinion of most of the persons on board, that this ice extended quite to the pole, from which they were then less than nineteen degrees; or, perhaps, that it was joined to some land to which it had been fixed from the earliest time. Our navigator was of opinion that it is to the south of this parallel that all the ice is formed which is found scattered up and down to the northward, and afterward broken off by gales of wind, or other causes, and brought forward by the currents which are always found to set in that direction in high latitudes. “Should there,” he observes, “be land to the south behind this ice, it can afford no better retreat for birds, or any other animals, than the ice itself, with which it must be wholly covered. I, who was ambitious, not only to go further than any one had been before, but as far as it was possible for man to go, was not sorry at meeting with this interruption; as it in some measure relieved us, or at least shortened the dangers and hardships inseparable from the navigation of the southern polar regions.”

The approximation of several fields of ice of different magnitudes, produces a very singular phenomenon. The smaller of these masses are forced out of the water, and thrown on the larger ones, until at length an aggregate is formed of a tremendous hight. These accumulated bodies of ice float in the sea like so many rugged mountains, and are continually increased in hight by the freezing of the spray of the sea, and the melting and then freezing of the snow which falls on them. While their growth is thus augmented, the smaller fields, of a less elevation, are the meadows of the seals, on which these animals at times frolic by hundreds.

The collision of great fields of ice, in high latitudes, is often attended by a noise, which, for a time, takes away the sense of hearing anything beside; and that of the smaller fields, with a grinding of unspeakable horror. The water which dashes against the mountainous ice, freezes into an infinite variety of forms, and presents to the admiring view of the voyager ideal towns, streets, churches, steeples, and almost every form which imagination can picture to itself.

After such notices of the ice-islands from the earlier voyagers, it may be interesting to know how they have appeared to later beholders; and this may be seen in the following account from the journal of a seaman who was in the well known “Arctic Expedition,” in 1850-51. Under the date of the thirtieth of June, 1850, he writes: “Moored to an iceberg; weather calm; sky cloudless, and ‘beautifully blue;’ surrounded by a vast number of stupendous bergs, glittering and glistening beneath the refulgent rays of a midday sun. A great portion of the crew had gone on shore to gather the eggs of the wild sea-birds that frequent the lonely ice-bound precipices of Baffin’s bay, while those on board had retired to rest, wearied with the harassing toils of the preceding day. To me, walking the deck and alone, all nature seemed hushed in universal repose. Whilst thus contemplating the stillness of the monotonous scene around me, I observed in the offing a large iceberg, completely perforated, exhibiting in the distance an arch, or tunnel, apparently so uniform in its conformation, that I was induced to call two of the seamen to look at it, at the same time telling them, that I had never read or heard of any of our arctic voyagers passing through one of these arches, so frequently seen through large bergs, and that there would be a novelty in doing so; and if they chose to accompany me, I would get permission to take the small boat, and endeavor to accomplish the unprecedented feat.

“They readily agreed, and away we went. On nearing the arch, and ascertaining that there was a sufficiency of water for the boat to pass through, we rowed slowly and silently under, when there burst upon our view one of the most magnificent specimens of nature’s handiwork ever exhibited to mortal eyes; the sublimity and grandeur of which no language can describe, no imagination conceive. Fancy an immense arch of eighty feet span, fifty feet high, and upward of one hundred feet in breadth, as correct in its conformation as if it had been constructed by the most scientific artist, formed of solid ice, of a beautiful emerald green, its whole expanse of surface smoother than the most polished alabaster, and you may form some slight conception of the architectural beauties of this icy temple, the wonderful workmanship of time and the elements. When we had got about half-way through the mighty structure, on looking upward, I observed that the berg was rent the whole breadth of the arch, and in a perpendicular direction to its summit, showing two vertical sections of irregular surfaces, ‘darkly, deeply, beautifully blue,’ here and there illuminated by an arctic sun, which darted its golden rays between, presenting to the eye a picture of ethereal grandeur, which no poet could describe, no painter portray. I was so enraptured with the sight, that for a moment I fancied the ‘blue vault of heaven’ had opened, and that I actually gazed upon the celestial splendor of a world beyond this. But, alas! in an instant the scene changed, and I awoke as it were from a delightful dream, to experience all the horrors of a terrible reality. I observed the fracture rapidly close, then again slowly open. This stupendous mass of ice, millions of tuns in weight, was afloat, consequently in motion, and apparently about to lose its equilibrium, capsize, or burst into fragments.