ica, and the islands from Chiloe to Cape Horn, also the West Indies, England and Scotland, Corsica and Sardinia, and Madagascar, are good examples of continental islands.

8. Pelagic islands are mostly volcanic or coral formations which have risen from the bed of the ocean, far from land, and independent of the continents. In form they are generally round, and are mostly found in groups. Single pelagic islands, like St. Helena, are rare. Although they sometimes rise thousands of feet above the sea, they are probably the tops

of mountains whose bases

are far down in the fathomless retreats of the ocean.

9. In July, 1831, a new volcanic island appeared near Sicily, in the Mediterranean Sea, caused by the bursting forth of a volcano. An island was formed there with a crater in its centre. This was called Graham Island; and although it rose from a part of the sea where the water was 100 fathoms deep, and continued to grow till it was three miles in circumference and above 200 feet high, it afterward gradually diminished in size, and finally, after

a few weeks, disappeared beneath the waves.

1.

LESSON III.-CORAL ISLANDS AND REEFS.

DEEP in the wave is a coral grove,

Where the purple mullet and gold-fish rove,
Where the sea-flower spreads its leaves of blue,

That never are wet with falling dew,

But in bright and changeful beauty shine,

Far down in the green and glassy brine.-PERCIVAL.

2. The "great and wide sea, wherein are things creeping innumerable, both småll and great beasts," contains countless multitudes of living beings scarcely larger than a pin's head, which are constantly engaged in taking from the sea-water the lime it holds in solution, and, in the form of "coral groves,' building up islands and reefs, some of which are a thousand miles in extent. Prof. Dana calculates that there are in the

South Sea nearly 300 coral islands, the work of these "jellylike specks."

3. There are four different kinds of coral formations in the Pacific and Indian Oceans, called lagoon islands or atolls, encircling reefs, barrier reefs, and coral fringes. They are nearly all confined to tropical regions; the atolls to the Pacific and Indian Oceans alone. Atolls, of which the annexed

An atoll of the Pacific Ocean, covered with vegetation.

cut is a fair representation, consist of a circular ring of coral surrounding a shallow lake or lagoon of water. Encircling reefs surround mountainous islands at some distance from the shore. Barrier reefs are similar, but differ in their position in respect to the land. The largest barrier reef is the Australian, which extends more than 1000 miles.

4. On these bare reefs of coral the storms and waves of the ocean gradually deposit mud, sand, and sea-weed, until at length a kind of soil is formed. Seeds from the neighboring or distant lands are driven to the desolate isle, and, finding a soil suited to them, germinate and grow, until finally the ocean rock is covered with verdure. The mariner has visited the

"sea-snatched isle," and

"Wandered where the dreamy palm
Murmured above the sleeping wave:
And through the waters clear and calm
Looked down into the coral cave,
Whose echoes never had been stirred
By breath of man or song of bird."

5. The whole of the Pacific Ocean is crowded with islands of the same architecture, the produce of the same insignificant architects. An animal barely possessing life, scarcely appearing to possess volition, tied down to its narrow cell, ephemeral in existence, is daily, hourly creating the habitations of

men, of animals, of plants. In the vast Pacific it is founding a new continent; it is constructing a new world. This process is equally visible in the Red Sea, which is daily becoming less and less navigable, in consequence of the growth of its coral rocks; and the day is to come when perhaps one plain will unite the opposed shores of Egypt and Arabia.

6. These are among the wonders of His mighty hand: such are among the means which He uses to forward His ends of benevolence. Yet man, vain man, pretends to look down on the myriads of beings equally insignificant in appearance, because he has not yet discovered the great offices which they hold, the duties which they fulfill in the great order of na

ture.

LESSON IV. THE CORAL INSECT.*

[The representations here given are the united stony cells or habitations of the coralbuilding zoophytes, each species having its own peculiar structure. Every minute portion of this calcareous or lime rock is more or less surrounded by a soft animal substance (the zoophyte), capable of expanding itself, but otherwise fixed to its habitation; yet, when alarmed, it has the power of contracting itself almost entirely into the cells and hollows of the hard coral. These soft parts become, when taken from the sea, nothing more in appearance than a brown slime spread over the stony nucleus. Yet these jelly-like animals are the builders of the coral reefs. See Seventh Reader for a description of this class of animals.]

COMMON CORAL-BUILDING ZOOPHYTES.-1. Meandrina labyrinthica. 2. Astrea dipsacea. 3. Madrepora muricata. 4. Porites clavaria. 5. Caryophyllia fastigiata. 6. Oculina hirtella.

1. TOIL on! toil on! ye ephemeral train,

Who build in the tossing and treacherous main;

Toil on-for the wisdom of man ye mock,

With your sand-based structures and domes of rock;

Your columns the fathomless fountains lave,

And your arches spring up to the crested wave;
Ye're a puny race thus to boldly rear

A fabric so vast in a realm so drear.

2. Ye bind the deep with your secret zone,

The ocean is sealed, and the surge a stone;

Fresh wreaths from the coral pavement spring,
Like the terraced pride of Assyria's king;

*The little coral-building animal, or polyp, was long ago called the coral insect, a term quite improper, but one that is still retained in popular use.

The turf looks green where the breakers rolled;
O'er the whirlpool ripens the rind of gold;
The sea-snatched isle is the home of men,

And mountains exult where the wave hath been.
3. But why do ye plant 'neath the billows dark
The wrecking reef for the gallant bark?

There are snares enough on the tented field,
'Mid the blossomed sweets that the valleys yield;
There are serpents to coil ere the flowers are up;
There's a poison-drop in man's purest cup;
There are foes that watch for his cradle breath,
And why need ye sow the floods with death?
4. With mouldering bones the deeps are white,
From the ice-clad pole to the tropics bright;
The mermaid hath twisted her fingers cold
With the mesh of the sea-boy's curls of gold,
And the gods of ocean have frowned to see
The mariner's bed in their halls of glee;
Hath earth no graves, that ye thus must spread
The boundless sea for the thronging dead?

5. Ye build-ye build-but ye enter not in,

Like the tribes whom the desert devoured in their sin;
From the land of promise ye fade and die,

Ere its verdure gleams forth on your weary eye;
As the kings of the cloud-crowned pyramid,
Their noteless bones in oblivion hid,

Ye slumber unmarked 'mid the desolate main,

While the wonder and pride of your works remain.

1.

Terraced.

LESSON V.-MOUNTAINS.

MRS. SIGOURNEY.

Columnar.

Serrated.

Peaked. Volcanic.
FORMS OF MOUNTAINS.

THOU, who would'st see the lovely and the wild
Mingled in harmony, on Nature's face,
Ascend our rocky mountains, Let thy foot

Dome-shaped.

Fail not with weariness; for on their tops

The beauty and the majesty of earth,

Spread wide beneath, shall make thee to forget

The steep and toilsome way. There, as thou stand'st,
The haunts of men below thee, and above,

The mountain summits, thy expanding heart

Shall feel a kindred with that loftier world

To which thou art translated, and partake

The enlargement of thy vision. Thou shalt look

Upon the green and rolling forest tops,

And down into the secrets of the glens

And streams, that, with their bordering thickets, strive
To hide their windings. Thou shalt gaze at once,

Here on white villages, and tilth, and herds,

And swarming roads; and there, on solitudes

That only hear the torrent, and the wind,
And eagle's shriek.-BRYANT.

2. "There is a charm," says Howitt, "connected with mountains, so powerful that the merest mention of them, the merest sketch of their magnificent features, kindles the imagination, and carries the spirit at once into the bosom of their enchanted regions. How the mind is filled with their vast solitude'! how the inward eye is fixed on their silent, their sublime, their everlasting peaks'! How our heart bounds to the music of their solitary cries, to the tinkle of their gushing rills, to the sound of their cataracts!

66

3. When we let loose the imagination, and give it free charter to range through the glorious ridges of continental mountains, through Alps, Apennines, or Andes, how is it possessed and absorbed by all the awful magnificence of their scenery and character! by the sky-ward and inaccessible pinnacles, the

"Palaces where nature thrones
Sublimity in icy halls'!

the dark Alpine forests'; the savage rocks and precipices'; the fearful and unfathomable chasms filled with the sound of ever-precipitating waters'; the cloud, the silence, the avalanche, the cavernous gloom, the terrible visitations of heaven's concentrated lightning, darkness, and thunder'; or the sweeter features of living, rushing streams, spicy odors of flower and shrub, fresh spirit-elating breezes sounding through the dark pine grove'; the ever-varying lights and shadows, and aerial hues; the wide prospects', and, above all, the simple inhabitants'!"

4. But beyond their moral grandeur and their charms of scenery, mountains subserve some very important purposes in the great economy of nature. Their influence upon the temperature and fertility of vast regions, and upon the formation and direction of clouds and air-currents, will be noticed in the lessons on the atmosphere. They are also the most com