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228. The Great Falls of the Missouri are the grandest in all sedimentary accumulations which they deposit at their mouths, North America, those of Niagara excepted; and although the producing formations of land, and dividing the main stream latter exceed the former with respect to volume of water, depth into branches. Such formations are called deltas, from their of descent, and awful grandeur, yet the former are far more correspondence to the shape of the Greek letter A (delta). diversified and beautiful. These falls are within sixty geo
231. The delta of the Misgraphical miles of the easternmost range of the Rocky Mount
sissippi consists of a long, narains. They were discovered by Captain Lewis while engaged
row tongue of land protruding in exploring the Missouri. Hearing a sound like that of a fall
for 50 miles into the Gulf of of water, he proceeded in the direction of it. " As he ad
Mexico, at the end of which vanced, a spray arose above the plain like a column of smoke,
are numerous channels of disand vanished in an instant. Toward this point he directed his
charge. This extensive forsteps; and having traveled seven miles after first hearing the
mation has been produced by sound, he reached the falls about mid-day. The hills as he
the deposit of the sedimentary approached were difficult of access, and 200 feet high. Down
South Poss .
matter brought down by that these he hurried with impatience, and seating himself on some
mighty stream. The rate of rocks under the center of the falls, enjoyed the sublime specta
permanent advance of the new cle of this stupendous cataract, which since the creation has land has been very slow, not exceeding, it is supposed, one been lavishing its magnificence on the desert, unknown to mile in a century.* civilization.”
232. It has been calculated that the mean annual amount 229. The most noted falls of the Eastern Continent are Terni, of solid matter which the water of the Mississippi contains Italy, a fall of the Velino, of
is about reas of its weight, and that it is equal to about zoro 300 feet, usually regarded as of its volume. It has also been estimated that the quanthe finest European cataract; tity of solid matter annually brought down by the river is Staubach, near Lauterbrun- 3,702,758,400 cubic feet, an amount which would cover over nen, in Switzerland, a per- eleven miles square one foot deep. pendicular descent of 800 233. The waters of the Ganges contain a much greater profeet; Rhinefall, near Schaff
portion of sedimentary matter, hausen, a fall of the river
particularly during the season of Rhine in three distinct branch
the rains, which lasts about four es over a precipice upward
months. The average quantity ward of 80 feet high; Reich
of solid matter suspended in the enbach, canton of Bern, 2
water during such times was by series of six falls, amounting
weight oth part; and the solid to 1,000 feet; Ache, a small
matter discharged is žoth part in river of Bavaria, descending
bulk, or 577 cubic feet per second. in five falls 2,000 feet; Evan
The total annual amount of mud son, a torrent of Mount Rosa, discharged is estimated at 6,368,077,440 cubic feet, a mass
1,100 feet; Cauvery, southern equal in weight and bulk, it has been calculated, to eighty-two India, two grand falls near Seringapatam 810 feet; Girsupah, of the great pyramids of Egypt. The Hoang-Ho, which trav. near a town of that name in the western Ghauts, a single fall erses the great alluvial plain of China, is supposed to bring down of a considerable stream, 872 feet; the cataracts of the Nile, in one hour 2,000,000 cubic feet of earth, which so thickens and in Nubia and southern Egypt, of ancient celebrity; and Vic- colors the ocean by its discharges as to originate the name of toria Falls, on the Zambezi, which are described as scarcely the Yellow Sea. less grand than Niagara.
234. Rivers are grouped into two grand classes, the oceanic and the continental. Oceanic rivers are those which flow direct into the ocean, or into waters communicating with it. They form four distinct systems, belonging respectively to the
Arctic, Atlantic, Pacific, and Indian oceans.
I. SYSTEM OF THE ARCTIC OCEAN.
Length in RIVERS-(CONTINUED).
miles. . Eastern Siberia...... Lena..
. Arctic Ocean .....2,400 230. The termination of rivers is commonly by a single
.Northern Siberia.. .Ditto.... ..1,150 mouth, as in the instances of the St. Lawrer.ce and the Hudson;
.Ditto... ..2,900 but many streams, flowing through alluvial regions, carry along Obi ..
. Western Siberia..
Gulf of Obi. ..2,530 Qu-stions.-228. The Great Falls of the Missouri ? Give an account of its discovery. Questions.—Total annual amount ? The Iloang-Ho ? 234. Tivers, how grouped ? 229. Give the particulars of the following falls and rapids : Terni, Staubach, Rhinefall, Oceanie rivers ? Systems ? Name the principal rivers belonging to the system of the Reichenbach, Ache, Evanson, Cauvery, Girsupah, Nile, Victoria. 230. Termination of Arctic Ocean. Atlantic Ocean. Pacific Ocean. Indian Ocean. rivers ? Sedimentary arcumulations ? Deltas? 231. Delta of the Mississippi? The rate of its formation ? 232. Proportion of the sedimentary matter? Amount annually brought down? 233. Sedimentary matter in the Ganges ?
* Sir Charles Lyell
DELTA OF THE GANGES.
1,200 237. The proportional quantity of water discharged by some
Length in River..
... Arctic Ocean .....
Streams north of the African
Sahara lost in sands.
.Lakes and swamps.
.Great Salt Lako.
.. Baltic Sea
Many other streams in Utah
Territory are lost in sands,
marshes, or lakes. Loire.. .France ....
. Bay of Biscay..... 570 236. The magnitude of rivers depends upon the area of their Rhone.. Switzerland, France... .Mediterranean. 490
basins, the rain-producing character of the climate, and the Danube.. Austrian Empire, Turkey... Black Sea. .1,630
arrangement of the surrounding mountains with reference to Dnieper . Southern Russia ...
the prevailing winds. Lieut. Maury thus accounts for the vast
.1,100 Nile (Blue N.). Abyssinia, Nubia, Egypt.... Mediterranean....2,000 rivers of the South American continent: “The northeast and Senegal.. Western Africa
Atlantic Ocean. sro southeast trade-winds, as they come across the Atlantic, filled Niger. .Ditto....
Gulf of Guinea. ...2,500 with moisture, go full charged into the interior, dropping it in Gariep.... . Southern Africa.. Atlantic Ocean. ... .1,000
showers as they go, until they reach the snow-capped summits Saskatchewan... British America..
1,920 St. Lawrence. .Ditto...... . Atlantic Ocean ...2,070
of the Andes, where the last drop, which that very low temMississippi-Missouri ....Central North America.. .Gulf of Mexico....4,100 perature can wring from them, is deposited to melt and feed Rio del Norte .Mexico
..Ditto..... .1,400 the sources of the Amazon and the La Plata, with their trib-
Caribbean Sea.... 800) utaries.”
. Atlantic Ocean
of the principal rivers has been estimated as follows: St. Francisco .Ditto.
179 Plata. .Ditto.
250 Loire. .10 Euphrates
60 St. Lawrence. 112 III. SYSTEM OF THE PACIFIC OCEAN.
.12 | Yang-tse-Kiang .258 Amazon.. .1,280 Yang-tse-Kiang Ditto.
.36 | Lena. Meinam Siam
.Gulf of Siam 900 238. Many rivers are subject to periodical inundations. It is Cambodia. .
Tibet, Cochin China... .China Sea.. .2,000 to the annual overflowings of the Nile that Egypt owes her Columbia. Oregon.
..Pacific Ocean .....
fertility. The rise commences about the 21st of June, attains Colorado Utah, New Mexico.. ..Gulf of California. 900
its greatest height near the middle of September, and gradually IV. SYSTEM OF THE INDIAN OCEAN.
diminishes to the time of the winter solstice. Both the MissisEuphrates Western Asia.
Persian Gulf......1,600 sippi and the Missouri have annual floods during the spring Tigris .. .Ditto....
980 months. Among the other streams subject to overflow are Indus .. Northern India..
.Arabian Sea. .1,700 the Orinoco, Amazon, Euphrates, Tigris, etc.
.Bay of Bengal....1,460
.2,000 Irawaddy.. . Tibet, Birman Empire. .Ditto...
.1,200 Murray South Australia...
Encounter Bay ...1,000 235. Continental rivers are those which are confined exclusively to the continents, and discharge themselves into completely insulated lakes, or are lost in sands, deserts, or swamps. The principal continental rivers are stated in the following table: Rivers.
European Russia. ... .Caspian.
VIEW ON THE NILE
239. The following beautiful extract relates to the historic associations Sir or Siboon.. Ditto.....
of rivers : “The rivers of the old world, while subordinate to those of the Helmund... Afghanistan
.Lake Zurrah. new in point of magnitude, have a historic and sacred interest in many Yarkand. . Central Asia..
.Lake Lopnor. instances wholly wanting to the latter. The Danube recalls the struggle Many streams in Central Asia
of the ancient civilization with overwhelming barbaric invasions; the Tiber terminate in insulated lakes,
revives the story of Roman greatness; the Nile associates itself with the or are lost in desert sands.
colossal power of the Pharaohs; the Tigris and Euphrates are connected
Questions.—285. Continental rivers ? Name the principal continental rivers, the coun. tries through which they flow, and their places of termination. 236. Upon what does the magnitude of rivers depend? The large rivers of South America ?
Questions.—287. State the proportional quantity of water discharged by some of the principal rivers. 238. Inundations of rivers ? Overflowings of the Nile? or other rivers ? 289. What is said of the rivers of the old world? Illustrate.
with the mighty dynasties of Assyria and Babylon, the captivity of God's 243. The Missouri has its Jryın in tne Rocky Mountains, chosen people, and that momentous hour when the hand of retributive
and runs for 2,500 miles in a southeasterly direction before justico unfolded the doom of monarch and of nation at a profane festivity
it joins the Mississippi, making a total distance, from its source of the royal house ; while the Jordan is imperishably linked with far more stupendous transactions : the miracle which divided its waters at the in
to its entrance into the Gulf of Mexico, of more than 4,000 gress of Israel into the land of promise ; and that voice from heaven which miles. It is navigable from the point where it unites with the proclaimed the character of the Messiah at his baptism in the stream, Mississippi up to the base of the Rocky Mountains, where the placing his right to the universal homage of man, supported by the design Great Falls occur (in latitude 46° 50'). of his mission, on the firm ground of his Divine nature : “This is my be
244. During the period of the annual floods, large tracts loved Son, in whom I am well pleased.'”.
of the adjoining country are overflowed, and immense damage done to property. Artificial embankments, called levees, are
constructed along the lower course of the Mississippi to prevent LESSON VI.
inundation; but in seasons of high floods they are often broken
through by the force of the waters, forming what are known as RIVER SYSTEMS OF THE WESTERN CONTINENT.
crevasses. About one fifth of the whole surface of the State 240. In no portion of the world are' rivers found upon so of Louisiana is periodically overflowed. magnificent a scale as on the continent of North and South 245. The Ohio is, next to the Missouri, the most important America. The magnitude of these streams is owing to a variety of the tributaries of the Mississippi ; it is formed by the junction of causes, some of which have been described ; as the situation of the Monongahela and the Alleghany rivers, which unite their and direction of the great mountain ranges, the extent of the waters at Pittsburg, where the river becomes navigable. The river-basins, etc.: others will be explained in a subsequent Ohio, about 950 miles in length, and from four hundred yards part, which treats of wind, rain, etc.
to upward of three quarters of a mile in breadth, flows through 241. NORTH AMERICAN RIVERS.—The continent of North one of the most fertile portions of the Mississippi Valley. It America may, with reference to its drainage, be divided into has no fall, except a rocky rapid of 22} feet descent at Louisfour grand divisions : (1) The Atlantic slope, or that part which ville, around which a canal has been constructed sufficiently is drained by the rivers tributary to the Atlantic Ocean; (2) capacious to admit steamboats, though not of the largest class. the Valley of the Mississippi, lying between the Rocky and 246. Among the other principal streams in the Valley of the Alleghany mountains ; (3) the region to the west of the Rocky Mississippi are the following: the St. Peters, Iowa, Des Moines, Mountains, the streams of which are tributary to the Pacific St. Croix, Wisconsin, and Illinois rivers, tributaries to the Ocean; (4) the northern slope drained by streams tributary to Mississippi above, and the Ohio, Arkansas, and Red rivers Hudson Bay and the Arctic Ocean.
below, the junction of the Missouri; the Yellow Stone, Platte, 242. The Mississippi is the largest of the North American Kansas, and Osage rivers, tributaries to the Missouri ; and the rivers; it waters the southern half of the great plain, and brings Scioto, Miami, Wabash, Kanawha, Licking, Kentucky, Green, to the sea the drainage of upward of a million of square miles. Cumberland, and Tennessee rivers, tributaries to the Ohio. It rises in the small lake of Itasca, at an elevation of only 1,490 247. The St. Lawrence is the second great river of the feet above the level of the sea, and flows in a southerly direction North American continent, and by far the largest of the to its termination in the Gulf of Mexico, after a course of 2,400 streams draining the Atlantic slope. Its channel from Lake miles. The Mississippi is navigable for 2,000 miles to the Falls Ontario to the sea is about 700 miles long, but (including the of St. Anthony, a distance of about 400 miles below its source. great chain of the lakes from which it derives its waters) the
whole length, from the mouth of the St. Law. rence to the western extremity of Lake Superior, is 1,880 miles. Above Montreal, rapids occur which interrupt its navigation. During four months of the year the navigation is completely stopped by the ice.
248. Of the other streams draining the Atlantic slope, the principal are the Connecticut (400 miles), the Hudson (325 miles), the Delaware (300 miles), the Susquehanna (450 miles), the Potomac (400 miles), the James (450 miles), the Roanoke (350 miles), the Pedee (350 miles), the Santee (350 miles), the Savannah (400 miles), and the Altamaha (400 miles),—all of which flow into the Atlantic Ocean. The Appalachicola (600 miles) and the Mobile, farther to the westward,
Questions.—240. Magnitude of the American rivers ? To what owing ? 241. How may the continent of North America be divided with reference to its drainage ? First divi. sion ? Second ? Third ? Fourth ? 242. The Mississippi? Its source, direction, and termination? How far navigable? 243. The Missouri ? How far navigable ?
Questions.—244. Floods ? Artificial embankments ? 245. The Ohio? Its length, etc.? Falls ? 246. Tributaries to the Mississippi above the junction of the Missouri ? Below the junction of the Missouri ? Tributaries to the Missouri ? To we Ohio? 247. The St. Lawrence ? Its length from Lake Ontario? Its whole length, including the lakes ? Rapids ? Ice ? 248. Other streams draining the Atlantic slope? Their navigability? The Hudson, how far navigable for the largest ships ? For steamers ?
• Rev. Thomas Milner.
RIVER SYSTEMS OF THE WESTERN CONTINENT.
flow into the Gulf of Mexico. Most of these rivers are naviga-tween the opposite shores of the Atlantic and Pacific oceans.
249. The principal rivers draining the region to the west
LESSON. VII. mento (420 miles), and the Colorado (840 miles). Columbia,
RIVER SYSTEMS OF THE WESTERN CONTINENT—(CONTINUED). the most considerable of these, receives several important tributaries, the largest of which is the Lewis. The river Sacramento 252. SOUTH AMERICAN RIVERS.—The three principal rivers waters the northern half of the valley lying between the Sierra of South America are the Orinoco, the Amazon, and the La Nevada and the coast range of California, and forms at its Plata, which drain respectively the northern, middle, and southmouth the harbor of San Francisco: immediately above this ern portions of the great plain. outlet it is joined by the San Joaquin, which drains the south- 253. The Orinoco (about 1,200 miles long) rises in the mountern half of the valley, and carries off the waters of Lake Tulare. ains of Guiana. About 130 miles below its source it sends off The streams tributary to the Sacramento and San Joaquin, to the southward a branch called the Casiquiare (200 miles in which flow in from the west, drain the gold regions of Cali- length), which joins the river Negro, a tributary of the Amazon, forria.
and thus effects a natural communication (navigable for boats) 250. Of the streams draining the northern slope of North between the basins of these two great rivers. America two divisions may be made,—one embracing the Nel- 254. The principal tributaries of the Orinoco are the Guavson, Churchill, and other rivers flowing into Hudson Bay; and iare, Meta, and Apure (rising in the Andes), on its left bank; the other, the Mackenzie, Coppermine, and other streams flow- the Ventuari, Caura, and Caroni, on the right. Below the ing into the Arctic Ocean. The most considerable of these village of Angostura, 280 miles from the mouth of the Orinoco, streams is the Mackenzie, which issues from the western ex- no impediments to its navigation occur: above this its course tremity of the Great Slave Lake. During the summer it pours is occasionally interrupted by rapids, but in general it presents a vast flood of waters into the sea, but is obstructed by ice a deep and navigable channel nearly to its source. during nine months of the year.
255. The Amazon (called the Maranon in the upper portion 251. The Rio del Norte is a considerable stream of 1,400 of its course) rises in the small lake of Lauriococha, upon the miles in length, which rises in the southern part of the Rocky table-land of Pasco, amid the highest parts of the Peruvian Mountains and runs southwesterly into the Gulf of Mexico. To Andes. Thence it flows in a northerly course until it leaves the south of this stream are few rivers of any considerable the mountains, and afterward crosses the great plain in an length. The San Juan, in Central America, possesses consid- easterly direction to the Atlantic Ocean. The whole length erable interest from its having afforded, since the discovery of of the Amazon is a little short of 3,900 miles. gold in California, the principal channel of communication be- 256. The tributaries of the Amazon are numerous and on a
grand scale, some of them being equal to the largest streams of the Old World. The principal are the Napo, Putumayo or Ica, Japura, and Negro, on the left bank; the Huallaja, Ucayali, Javary, Jutay, Jura or Hyaruha, Teffe, Purus, Madeira, Tapajos, Xingu or Chingua, and Tocantins, upon the right. The Madeira has a course of more than 2,000 miles before it joins the Amazon.
257. At the distance of 700 miles below its source the Amazon has a width of 800 yards, and during the last 450 miles of its course it is nowhere less than four miles in width, and at its mouth the channel is fifty miles across.
A recent exploration of this river* has proved that it is navigable for vessels of the largest class, during a considerable part of the year, from its mouth to the very foot of the Andes, a distance of about 3,500 miles. So great is the amount of water which it brings down that its freshness is perceptible at a distance of more than 500 miles from
the coast. Questions.—249. The principal rivers draining the third division ? The Columbia ? Questions. Its course? Length ? 256. What is said of the tributaries of the Amazon ? Bacramento ? San Joaquin? Gold regions, how drained ? 250. What two divisions of the The principal tributaries on the left bank? Upon the right bank? The Madeira? 257. streams draining the northern slope? The Mackenzie ? 251. The Rio del Norte ? San Width of the Amazon? How far navigable ? Illustrate the amount of water it brings down. Juan? 252. The three principal rivers of South America ? 253. The Orinoco? Casiquiare ? 354. The principal tributaries of the Orinoco? Its navigability? 255. The Amazon ?
* By Lieut. Herndon.
258. The Rio de la Plata is a broad fresh-water estuary, of the whole surface of the continent. The Volga is naviwhich receives the waters of the Parana and Uruguay. The gable through nearly its whole length, and has considerable Parana has its rise in the mountains of Brazil, and, reckoning depth. During the greater part of winter it is frozen over, but from its most distant source to the mouth of the Rio de la Plata, at other times is the highway of a most extensive traffic. is 2,350 miles in length. About 760 miles above the sea it re- 264. The Danube, 1,630 miles, is the second of the rivers ceives the Paraguay, which has a course of about 1,260 miles. of Europe, both in length of course and in the area of its basin, The Uruguay (1,000 miles long) flows nearly parallel to the which is 310,000 square miles in extent. It rises in the Black lower course of the Parana. Both the Parana and Paraguay Forest, to the north of Switzerland, at a height of 2,200 feet are navigable for vessels of considerable draft to a distance of above the level of the sea, and flows in an easterly direction nearly 1,000 miles.
across the plateau of Bavaria, through Austria, the plain of 259. Among the other principal rivers of South America are Hungary, and between Bulgaria and Wallachia, until it enters the Magdalena (860 miles), which flows into the Caribbean the Black Sea. Sea, and the Atrato (300 miles), into the Gulf of Darien. The 265. The Danube is navigable from its mouth up to Ulm Essequibo, Demerara, Berbice, Corentyn, Surinam, Maroni, (10° east longitude), or throughout nearly the whole length and Oyapok flow into the Atlantic to the eastward of the mouth of its course, excepting between the towns of Moldova and of the Orinoco, To the east and south of the Amazon are the Gladova, where it passes, for a space of 60 miles, through a Maranhao, Parnahiba, St. Francisco (1,500 miles), and many succession of rapids and shallows. The principal tributaries are others belonging to the Atlantic coast. The Colorado (600 the Inn, the Drave, the Save, and the Morava, on the south (or miles) and the Negro (800 miles) flow into the Atlantic south- right-hand) bank; and the March, the Theiss, the Aluta, and west of the Rio de la Plata.
the Pruth, on the north side. All of these are rivers of con260. The rivers on the western coast of South America are siderable magnitude. very short; among the longest are the Biobio, in Chile, about 266. The other principal streams which flow into the Black 150 miles, and a few streams of nearly equal length to the Sea are the Dniester (1,200 miles), the Dnieper (1,200 miles), northward of the Gulf of Guayaquil.
and the Don (1,100 miles). The Dnieper is navigable from Smolensk to the sea, excepting for a distance of about 150 miles below-Kiev, within which its navigation is impeded by rocks and cataracts.
267. The Rhine rises in the Alps, at an elevation of 6,580 LESSON VIII.
feet, and flows in the upper portion of its course through Lake RIVER SYSTEMS OF THE EASTERN CONTINENT.
Constance. It has a length of 760 miles, and its basin is 70,000 261. EUROPEAN RIVERS.-Europe is divided into two principal river systems,—one embracing those streams which have a southerly direction, and flow into the Mediterranean, Caspian, and Black seas; the other comprising those which have a northerly course, and terminate in the North, Baltic, and White seas, and the Arctic Ocean.
262. In the west, these two systems are for the most part divided by the Alps and German mountains; but in the eastern part of Europe the division of the waters is' merely a ridge of the great plain slightly elevated above the general level. This watershed begins on the northern declivity of the Carpathian Mountains, about the 23d meridian, in a low range of hills running between the sources of the Dnieper and the tributaries of the Vistula, from whence it winds in a tortuous course along the plain to the Valdai table-land, which is its highest point, 1,200 feet above the sea. It then declines northward toward the Onega, about the 60th parallel, and lastly turns in square miles in area; at Basle (where it is 765 feet above the a very serpentine line to the Ural Mountains, near the 62d de level of the sea) its breadth is 800 feet, at Mentz about 1,700, gree of north latitude.
and at Cologne 1,400. It is navigable for boats as high up as 263. The Volga, which is the largest river of Europe, rises the Falls of Schaffhausen, a short dietance below Lake Conin the plateau of Valdai, at the height of 1,100 feet above the stance, and for vessels of some magnitude as high as Strassea; its entire course is 2,200 miles in length, and the area of burg. The current is generally rapid, flowing at the rate of its basin about 520,000 square miles, or nearly one seventh four or five miles an hour. Its principal affluents are the
Questions.—258. The Rio de la Plata ? The Parana? Paraguay ? Uruguay? How far are the Parana und Paraguay navigable ? 289. Other principal rivers of South America ? Rivers flowing into the Atlantic to the east of the mouth of the Orinoco? To the east and south of the Amazon ? To the south of the Rio de la Plata ? 260. The rivers of the western coast? Biobio ? 261. Into what two river systems is Europe divided ? 262. Division of the two systems in the western part?
Questions. In the eastern part ? Describe the course of the watershed through eastern Europe. 263. Give particalars of the Volga. How far navigable ? 264. Give particulars of the Danube. Its source, direction, and termination ? 265. Navigation of the Danube ? Tributaries ? 266. Other streams which flow into the Black Sea ? The Dnieper? 267. The Rhine ? Its length, extent of its basin, etc.? Its principal affluents?