Puslapio vaizdai
PDF
„ePub“
[ocr errors]

of Holland. The direction of the Hook is invariably that of the current.

The coasts of Europe offer numerous examples of these various forms of alluvial deposits. Lines of narrow banks, like those on the coasts of New Jersey and the Carolinas, have been described by M. Elie de Beaumont, on the shores of France, as, for instance, near Dieppe, and in the

department of Finisterre. On the other hand, the Bay of Biscay offers in its sands, (which are carried by the winds into the interior and formed into dunes,) a striking example of the bay-deposits. But it is the Netherlands that merit the greatest attention. Sand-banks are rare on the northwest coasts of France, but no sooner do we quit the Channel than we find them scattered throughout the North Sea. Holland itself is in a great measure formed of alluvial sand. Now these deposits are formed precisely on the spot most favorable to the formation of alluvial deposits : namely, where the tidal current, having passed through the Channel, enters the vast basin of the North Sea. The deposition of sand-banks in the North Sea is favored, moreover, by the meeting of two tides on the coast of Jutland, (one coming from the Channel and the other passing round the island of Great Britain,) forming what the hydrographers call a tide node, which implies, generally, a continual eddy, which is more favorable than any thing to the formation of sand-banks.

Considered in their general connection, the alluvial deposits of a continent should be looked upon as the product of a series of currents and eddies alternating with each other, the final result of which is to transport, in the direction of the food, the movable materials which the waves and atmospheric agents have detached from the coast-beaches. This is particularly striking on the coast of the United States. The alluvial deposits form, at first, only a narrow line on the coast of Florida; this line enlarges insensibly on the coasts of the Caro linas, Virginia, and New Jersey; it becomes wider on the coast of Massachusetts, and finally attains the maximum of its development in the Grand Bank of Newfoundland.

This process is of the highest importance in the economy of nature, if we consider that the banks thus formed by the tidal currents are the principal seats of animal life in the

It is upon the banks which border the coast of the United States that the most extensive fisheries are carried on, (particularly the St. George's and Newfoundland Banks,)

because these are the abodes of those myriads of invertebral animals (worms, mollusks, and zoophytes, which serve for the food of fishes, whilst the great depths of the ocean, at a short distance from the banks, are almost deserts.

The tides are not less important from the manner in which they influence river-deposits. Hitherto the formation of deltas, such as those of the Mississippi, the Nile, the Orinoco, and other rivers, has been attributed too exclusively to the great quantities of mud which these rivers transport. It seems to be forgotten that other rivers, such as the Amazon, the Rio de la Plata, the Delaware, and others, are not less muddy, and yet, instead of forming deltas at their mouths, they empty into wide bays.

Mr. Davis, on the contrary, shows that deltas are in an inverse ratio to the tides, so that they exist only where the tides are feeble or null; whilst we find estuaries wherever the tides are considerable. Take, for example, the rivers of the eastern coast of the United States, and most of the rivers of Europe which empty into the Atlantic Ocean. And this is perfectly natural. The tide, on entering a river, accumulates during the flood, and keeps back the water of the stream, so that when the ebb begins, the water, in escaping, forms a current strong enough to carry off to sea the principal part of the materials held suspended in the river-water. Mr. Davis remarks on this point, that where bars exist in such estuaries they are generally composed of sea-sand brought by the tide, and not of fluviatile deposits.

In connection with Mr. Davis, we have endeavoured to apply the above results to the study of the deposits of former geological epochs; and we think it is easy to show on a geological chart of the United States, that the same laws which now regulate the deposition of sand-banks have been in operation during the diluvial, tertiary, and cretaceous epochs ; the deposits of these epochs forming so many parallel zones successively following the great backbone of the Alleghanies.

The diluvial deposits, in Europe as well as in America, merit a special attention in this respect. No doubt, during the diluvial epochs, the plains of northern Germany as well as a great part of Scandinavia, and, on this continent, the coast of the United States from Florida to Canada, formed a series of banks and shoals, like the Banks of Newfoundland in our day, whilst the plains of the West, between the Alleghanies and the Rocky Mountains, formed a vast bay, comparable NO. V.

6

to the Gulf of Mexico, in which the sea deposited the fine sand and clay of the prairies, as it now deposits in the Gulf of Mexico the sand and mud that border the coast of Texas.

The results of the above researches may be summed up thus :

1st. The form and distribution of banks, and of alluvial formations in general, are, in a great measure, dependent on tides. They ought to be found everywhere where the tidal current is sufficiently abated to permit the materials held in suspension to be deposited. The finer and lighter materials must therefore be deposited in the calmer places.

2nd. The formation of submarine banks is indispensable to the maintenance of animal life, since they constitute the most favorable localities for marine animals.

3d. The formation of deltas, at the mouths of rivers, is in an inverse ratio to the force of the tide.

4th. The sedimentary deposits of the most recent geological epochs, being, in all respects, like the alluvial deposits of our day, we must hint that they were formed under the operation of the same laws.

5th. The form and extent of continents, so far as they are composed of sedimentary deposits, are thus dependent on astronomical laws, that is, on the attraction which the moon and the sun exert, and in all time have exerted on the liquid part of our planet.

ART. VI. - Cheap Postage. By Joshua LEAVITT, Corre

sponding Secretary of the Cheap Postage Association. Boston. 1848.

THERE is nothing which so surely makes a man write himself down an ass, as his vanity. It is just so with nations ; and the American people are often led, by indulgence in this weakness, to make themselves egregious asses in the eyes of intelligent foreigners. “You are the most free and enlightened nation upon the earth,” say the politicians; and the people cry, Amen! and straightway go and vote such smoothtongued orators into place and power.

According to the theory, our government, being composed of representatives of the people taken from among the citizens themselves, has no motive to do any thing, or to support any institution, which is hostile to the interests of the people ; but, according to the fact, it does do many such things. Among these is the imposition of a most unjust, unnecessary, and oppressive tax upon knowledge and intercourse among men, which is levied by means of an odious monopoly of the business of conveying letters. To this monopoly our“ enlightened people submit, and even think their "post-office privilege is a great boon, while a neighbouring nation has for years been in the enjoyment of a system compared to which ours is like a relic of the dark ages.

[graphic]

Any one who can see an inch into futurity, has only to examine our present system of postal arrangements, its imperfections and abuses, and to compare it with one that is perfectly feasible, in order to feel assured that in a few years men will look back upon it with that complacent contempt with which they now look back upon the mode in which they travelled before the days of steam-boats and rail-roads.

To say nothing of a journey to Washington or New York, matters of such grave import as to require “ a note read in meeting," asking the prayers of the pious for safe deliverance from perils by sea and perils by land, one could not make a journey even of a hundred miles without painstaking preparation and long-suffering endurance.

If a wise man, you prepared to start on Monday, so as to have the whole week for“ lee way.” You went on Friday or Saturday to the stage-office,” booked yourself, and paid the fare. On Sunday, about sunset, you might see some runner from the office speering about the neighbourhood, to make sure of the place and number of your dwelling, in order the more easily to find it in the gray of the morning You made a compact with the watchman to rap on your window an hour before the time of starting; or, you had some queer contrivance to awaken yourself, such as a bunch of keys, or old iron, suspended by a string passed across the lower part of a candle, which, in four or five hours, would burn down to the mark, set fire to the string, let fall the iron into a wash-basin, and so make racket enough to arouse you. You waked twenty times to see if the machinery was all in order, and at last got up before it gave the signal. You roused the maid, who bustled about to make ready your coffee, ham, and eggs, while you shaved your chin and packed your chest. At last you heard the distant horn; then the sound of rumbling

wheels, — of clattering hoofs ; — the “stage” is at the door.
You rush resolutely to the “entry,” and put on and button
up your overcoat with desperate haste ; you don your travel-
ling cap, and throw a heavy cloak over your shoulders, while
two men lift your heavy trunk, and strain and pull at great
straps, to bind it on behind the coach ; which done, they cry
“all right;" and you kiss your mother, wife, or sister, who
stands shivering on the doorway, holding a dressing-gown to-
gether with one hand, while the other, raised above her head,
supports the candle whose flickering light guides you down the
steps, and serves to tell the wondering neighbours, with night-
capped heads popped out of the windows, who is going away.
You take the back seat,” if you are old or feeble ; the mid-
dle one by the window, if you are hearty; or mount the box,
beside the jolly driver, if you are young and vigorous, and
want to see the country. Crack goes the whip! and away
you post, to pick up other passengers, and so pass an hour
preparing for the final start. At last you are fairly off; and
the horses go jog-trotting along the plain, walking up the hills,
galloping down the slopes, until you come to the changing
place.” You then get out, and warm your toes by the bar-
room fire, while the panting horses are taking off, and fresh
ones are put on; you treat your driver to a “horn,” (not
of tin,) which drunk, he lights his cigar, and, crying "all
aboard,” heaves his heavy carcass up into his box, picks
up the lines, and away you start again. Thus toiling on,
through all the tedious hours of the forenoon, stopping to
water the horses or to change them five or six times, you
arrive at the “half-way house," hungry as a hunter, and
happy that a quarter of your journey is done. After a hearty
dinner, you mount again and try to sleep away an hour or so,
while the rumbling carriage goes slowly on, with the occasional
variety of a “break-down” or an “overset," until, long after
dark, you arrive at the stopping-place for the night; and,
heated, tired, jaded out, you lie down, perchance in damp
sheets, with the poor satisfaction that you have got over nearly
fifty miles, and have only fifty more before you.

But now, you make the same journey by going quietly to the "station,” after breakfast, with no other impedimenta than your sack-coat and the last new novel ; you take your seat by the window; you finish the distance as you finish the first volume; you do your business, return home before night, and, if your wife asks you where you “ dined to-day,” you

[ocr errors]
« AnkstesnisTęsti »