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"Adjoining to it is Middle Moor, containing about 2,500 acres, spoken "of by Arthur Young as 'a watery desert,' growing sedge and rushes, "and inhabited by frogs and bitterns;-it is now fertile, well cultivated, "and profitable land."

The foregoing extract, from an account of the Drainage of the Fens on the eastern coast of England, is a text from which might be preached a sermon worthy of the attention of all who are interested in the vast areas of salt marsh which form so large a part of our Atlantic coast, from Maine to Florida.

Hundreds of thousands of acres that might be cheaply reclaimed, and made our most valuable and most salubri ous lands, are abandoned to the inroads of the sea;—fruitful only in malaria and musquitoes, always a dreary waste, and often a grave annoyance.

A single tract, over 20,000 acres in extent, the center of which is not seven miles from the heart of New York City, skirts the Hackensack River, in New Jersey, serv ing as a barrier to intercourse between the town and the country which lies beyond it, adding miles to the daily travel of the thousands whose business and pleasure require them to cross it, and constituting a nuisance and an eyesore to all who see it, or come near it. How long it

expense

will continue in this condition it is impossible to say, but the experience of other countries has proved that, for an of not more than fifty dollars per acre, this tract might be made better, for all purposes of cultivation, than the lands adjoining it, (many of which are worth, for market gardening, over one thousand dollars per acre,) and that it might afford profitable employment, and give homes, to all of the industrious poor of the city. The work of reclaiming it would be child's play, compared with the draining of the Harlem Lake in Holland, where over 40, 000 acres, submerged to an average depth of thirteen feet, have been pumped dry, and made to do their part toward the support of a dense population.

The Hackensack meadows are only a conspicuous exam. ple of what exists over a great extent of our whole seaboard;-virgin lands, replete with every element of fertility, capable of producing enough food for the support of millions of human beings, better located, for residence and for convenience to markets, than the prairies of the Western States, all allowed to remain worse than useless; while the poorer uplands near them are, in many places teeming with a population whose lives are endangered, and whose comfort is sadly interfered with by the insects and the miasma which the marsh produces.

The inherent wealth of the land is locked up, and all of its bad effects are produced, by the water with which it is constantly soaked or overflowed. Let the waters of the sea be excluded, and a proper outlet for the rain-fall and the upland wash be provided,-both of which objects may, in a great majority of cases, be economically accomplished, and this land may become the garden of the continent. Its fertility will attract a population, (espe cially in the vicinity of large towns,) which could no where else live so well nor so easily.

The manner in which these salt marshes were formed may be understood from the following account of the

"Great Level of the Fens" of the eastern coast of England, which is copied, (as is the paragraph at the head of this chapter,) from the Prize Essay of Mr. John Algernon Clarke, written for the Royal Agricultural Society in 1846.

The process is not, of course, always the same, nor aro the exact influences, which made the English Fens, gener ally, operating in precisely the same manner here, but the main principle is the same, and the lesson taught by the improvement of the Fens is perfectly applicable in our case.

"This great level extends itself into the six counties of “ Cambridge, Lincoln, Huntington, Northampton, Suffolk “ and Norfolk, being bounded by the highlands of each. "It is about seventy miles in length, and varies from "twenty to forty miles in breadth, having an area of more “ than 680,000 acres. Through this vast extent of flat "country, there flow six large rivers, with their tributary "streams; namely, the Ouse, the Cam, the Nene, the Wel"land, the Glen, and the Witham.

"These were, originally, naturai channels for conveying "the upland waters to the sea, and whenever a heavier "downfall of rain than usual occurred, and the swollen springs and rivulets caused the rivers to overflow, they must necessarily have overflowed the land to a great ex، tent.

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"This, however, was not the principal cause of the in"undation of the Fens: these rivers were not allowed a "free passage to the ocean, being thus made incapable of 66 carrying off even the ordinary amount of upland water "which, consequently, flowed over the land. The obstruc“tion was two-fold; first, the outfalls became blocked up "by the deposits of silt from the sea waters, which ac"cumulated to an amazing thickness. The well known "instances of boats found in 1635 eight feet below the "Wisbeck River, and the smith's forge and tools found at "Skirbeck Shoals, near Boston, buried with silt sixteen feet "deep, show what an astonishing quantity of sediment

" formerly choked up the mouths of these great rivers "But the chief hindrance caused by the ocean, arose from "the tide rushing twice every day for a very great dis "tance up these channels, driving back the fresh waters, "and overflowing with them, so that the whole level be came deluged with deep water, and was, in fact, one "great bay."

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"In considering the state of this region as it first at"tracted the enterprise of man to its improvement, we are to conceive a vast, wild morass, with only small, de"tached portions of cultivated soil, or islands, raised above "the general inundation; a most desolate picture when "contrasted with its present state of matchless fertility."

Salt marshes are formed of the silty deposits of rivers and of the sea. The former bring down vegetable mould and fine earth from the uplands, and the latter contribute sea weeds and grasses, sand and shells, and millions of animalculæ which, born for life in salt water only, die, and are deposited with the other matters, at those points where, from admixture with the fresh flow of the rivers, the water ceases to be suitable for their support. It is estimated that these animalculæ alone are a chief cause of the obstructions at the mouths of the rivers of Holland, which retard their flow, and cause them to spread over the flat country adjoining their banks. It is less important, however, for the purposes of this chapter, to consider the manner in which salt marshes are formed, than to discuss the means by which they may be reclaimed and made available for the uses of agriculture. The improvement may be conveniently considered under three heads:

First-The exclusion of the sea water.

Second-The removal of the causes of inundation from the upland.

Third-The removal of the rain-fall and water of filtra

tion.

The Exclusion of the Sea is of the first import ance, because not only does it saturate the land with water, but this water, being salt, renders it unfertile for the plants of ordinary cultivation, and causes it to produce others which are of little, or no value.

The only means by which the sea may be kept out is, by building such dykes or embankments as shut out the highest tides, and, on shores which are exposed to the action of the waves, will resist their force. Ordinarily, the best, because the cheapest, material of which these embankments can be made, is the soil of the marsh itself. This is rarely, almost never,-a pure peat, such as is found in upland swamps; it contains a large proportion of sand, blue clay, muscle mud, or other earthy deposits, which give it great weight and tenacity, and render it excellent for forming the body of the dyke. On lands which are overflowed to a considerable extent at each high tide, (twice a day,) it will be necessary to adopt more expensive and more effective measures, but on ordinary salt meadows, which are deeply covered only at the spring tides, (occur ring every month,) the following plan will be found prac tical and economical.

Locating the line of the embankment far enough back from the edge of the meadow to leave an ample flat out. side of it to break the force of the waves, if on the open coast, or to resist the inroads of the current if on the bank of an estuary or a river,-say from ten to one hundred yards, according to the danger of encroachment,-set a row of stakes parallel to the general direction of the shore, to mark the outside line of the base of the dyke. Stake out the inside line at such distance as will give a pitch or inclination to the slopes of one and a half to one on the outside, and of one to one on the inside, and will allow the necessary width at the top, which should be at least two feet higher than the level of the highest tide that is known ever to have occurred at that place. The width

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