It would be impossible to enumerate all the existing marshes : we may however observe that in Italy there are the Tuscan and the celebrated Pontine marshes, which are of great extent ; in France there are about 1,500,000 arpens, or French acres, of marshes, some of great surface, as that of Montoire near the mouth of the Loire, which has been worked for its peat for upwards of five hundred years, and gives constant employment to 8000 persons. Ireland contains about 3,000,000 acres of marsh ; the marsh or bog of Allen alone contains 300,000 acres, and there are others very extensive. England has had many marshes, particularly in Lincolnshire, Somersetehire, Kent, and Cambridgeshire ; Chester, Huntingdonshire, Lancashire, and Stafford havp also had extensive marshes, some of which contain embedded trees, but the improvements in drainage of modern times have ren dered them insignificant, except in a few maritime localities. Scotland is much diversified with marshy ground, as in Peebles ahire, Ayrshire, Stirlingshirc, Kinross, &c. As for Holland, the whole country is properly a drained marsh, and it still contains some extensive bogs which furnish peat. All the space along the coast from Holland to Denmark is little better than a succession of marsh and sand. Russia in Europe has marshes of vast extent, as those at the source of the Don, along the river Pripitz, and round the sea of Azoff, as also in Finland and the Baltic Provinces, in Lithuania and Poland. The eastern part of Prussia abounds in swamps. Norway and Sweden have some bogs, but little in proportion to their territory. In liesaarabia in Turkey, and all along the lower Danube, there are extensive marshes covered with reeds. In Hungary the marshes are estimated at 2,000,000 arpens. Switzerland has some considerable swampy patches, many of which are on the slopes of the mountains and in the higher valleys. In Spain and Portugal there are some extensive marshes; indeed they are more or less scattered all over Europe.
Asia has its marshes and swamps, but they are less common than in Europe, if we except the northern portion, where they are in great number and very extensive, as between the lower Ob and the Yenisei, and between this last river and the Lena. There is between the little Tanguska and the Yenisei the marsh called Lis, equal in extent to the great lake Ladoga, suspended as it were in the midst of rocky hills. The province of Okhotsk has many swampy forests. A large part of China is naturally swampy, but it is to a great extent drained by the numerous canals which intersect the country. Tonquin has .many marshes, and the peninsula of Malacca contains many of great extent. In India, the province of Oude has some extensive marshes covered with reeds, the retreat of great herds of wild buffaloes. The mouths of the greater part of the rivers of India are marshy, and large swamps are sometimes found along their course, as is the case with the Padder. There is a vast marsh in the valley of Cashmere, between the city of that name and the Wulur lake, from which indeed it is only vaguely separated. In the northern provinces there are many savan nahs, or wet meadows. There are swamps along the Euphrates; and those of Mesopotamia are hitter, sulphurous, and salt. In Persia the province of Ghilan, in other respects fertile and beautiful, is very un wholesome on account of its marshes and marshy forests. Mazenderan has also many swamps. The eastern side of the lake Aral is marshy. The steppes of the Kirghis abound in salt marshes and pools. The Asiatic islands, that is, all those that are of any extent, contain marshes : thus part of the coast of Sumatra is covered with extensive marshes, which have caused it to receive the name of "the pestiferous coast ;" the reeds are gigantic bamboos, and a continual fog hangs over the aquatic soil. Batavia, Samarang, and other places in the island of Java are reputed to be so unwholesome, in consequence of the stagnant waters and pestilential marshes, that the island has been named the grave of Europeans. The Philippine Islands have a great many peat bogs. Australia has much marshy ground along the coast, and immense swamps have been seen inland.
As for Africa, its interior is too little known to enable us to speak with any certainty of its marshes ; but the southern part, according to Barrow, has many and extensive swamps covered with reeds and saline plants. Some of the rivers on she east are Marshy at their embouchures,
which is also the case with the Quorra. Madagascar contains marshes, in which the singular Ravenala (Urania speciosa), a kind of palm, grows, remarkable for the size and disposition of its leaves, which are similar to those of the banana, and are employed by the natives as table-cloths, napkins, plates, dishes, and spoons.
America contains immense marshes. In the frigid zone of the New World, as far as known, fog-enveloped marshes have beau found. To the westward, in Russian America, the laud lying between the coast and the mountains is a slip of black swampy soil ; some of the marshy grounds are on the slopes of the mountains and retain the water like a sponge ; the verdure (being covered with moss of various kinds) gives them the appearance of firm land, but in endeavouring to pass them the traveller sinks up to the waist. On the opposite or east coast of America we find Newfoundland intersected by marshes and morasses. Lower Canada has neither marshes nor stagnant water. To the south of the great lakes of North America, and as far south as Mexico, the United States contain a great number of marshes, and some of them of great extent. The low lands of Mexico also contain massy swamps. The former intendencia of Vera Cruz is principally occupied with marshes and sands. South America contains a great abundance of extensive marshes, as on the upper Apure, au affluent of the Orinoco ; and the delta of the latter river is one vast swamp. The region which extends betweesi the Andes and the Pacific has little marshy ground, if we except Chaco, where there are many swampy valleys; but on the other hand the immense plains which occupy the whole interior of the continent, from the mountains of Caracas on the north to the Straits of Magalhaens on the south, contain a great number of extensive marshes. All the immense basin of the Amazon is covered with swamps and wet land and marshy forests, many of which, how ever, at certain seasons, form the bed of the enlarged rivers. To the south of the Campos Parexis, the provinces of Moxos and Chiquitos contain extensive marshes ; in the latter particularly there is the great lake or marsh of Xarayee. This marsh is temporary, however, being dry a great part of the year, and then covered with the corn-flag (Gladiolus) and other Iridece. In the province of Cordova are the swamp of Los Porongos, the Mar-chiquito, &c. In La Plata there is the great marsh of Ybera, formed by the infiltrations of the Parana. At the north-west extremity of the Pampa of Buenos Ayres is tho great reedy marsh called Los Canaverales, and along the whole course of the Rio Mendoza, and between that river and the foot of the Cordilleras, there are extensive marshes. They also exist on the upper part of Rio Negro. In short, we may say that all the immense region of the Pampas, or plains of South America, contains marshes. In ascending the coast we find the great island of Marajo at the embou chure of the Amazons, a considerable tract of which is a marsh, formed in part by the deposit from the water of the river, and in part by the sands of the sea. Farther north again the whole coast of French Guyana is a swamp.
This enumeration of the known marshes And swamps, though com prehensive, is however far from being complete. Very largo portions of the earth's surface still remain unexplored. Nevertheless it is certain that the extent of marshy ground is very groat; and probably it was formerly much greater, for a multitude of natural circum stances have greatly diminished marshes, and are still of them by degrees. On the other hand colonisation, and the consequent increase of population in the newly settled places, cause the clearing of forests and the draining of marshes to go on rapidly. There is no doubt that in proportion as the swamps are dried up the source of many diseases will be got rid of; but again, it may be doubtful whether the increased drought °cautioned by so vast a reduction of evaporating surface may not engender other diseases equally fatal with those which now spring from the superabundance of swampy ground; and it is possible that oven absolute sterility may result, in some cases, from imprudent drainage.