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the cup. The king was so angry with the bird that he dashed it to the ground in his anger, and killed it on the spot in his rage.
“ Just then one of his attendants came up, and the king, giving him the cup, desired him to wipe it clean, and to bring him some of the water. But he was so very thirsty that he had not patience wait for the filling of the cup, drop by drop, and, consequently, he directed the servant to climb up the rocks, and fill it at the spring itself.
“The servant obeyed his master, and when he had reached the top of the rock he discovered there a crystal spring, at which he filled the cup. But a little lower down lie caught sight of a huge serpent, lying dead, with its head resting in the course of the stream, and polluting the water with the poisonous foam that issued from its jaws.
“He presented the cup, and told his master of his discovery. The king was much affected by the thought that he had, in his blind rage, destroyed the faithful bird who had endeavoured to save his master from ill, even at the risk, and finally at the cost of his own life.”
EXERCISE.-63. PARSING, ETC. 1. Analyse and parse the last paragraph in the above lesson. 2. Write out all the proper names in the lesson.
3. Enumerate the adverbs in the third paragraph, commencing, “The falcons are trained ;' and point out the words that are qualified by them.
4. What is the difference between a proper noun ard a common noun ? Give examples of each.
5. Parse the following sentences :-(a). Once upon a time, a king of Persia went out hawking. (b). The king was so angry with the bird that he dashed it to the ground in his anger.
THE EARTH'S CRUST. sci-ence (L. scio, to know], certain knowledge, the knowledge of many digested and arranged so as to be readily attained by any inquirer. sur-face (L. superficies, from super, above; facio, to make), the exterior or outside of anything. im-mense (L. immensus, from in, negative; metior, tu measure), very large, vast in extent. SCIENCE has taught us that our earth, which appears to be merely a vast flat surface, is in reality an immense
globe. What the centre of this great globe is we do not know, and probably shall never discover. But what the outer surface or crust consists of, and how its varieties have been formed, we learn from geology.
It is not possible to drill a tunnel right through the earth, but we can and do dig a considerable way down into its crust; and by so doing, in a great number of spots distant from each other, we learn the general characteristics of the world's formation.
Suppose, however, it were really practicable to excavate a tunnel right through the globe, and that such a gigantic work were undertaken, the first thing done would be to make borings, in order to discover the kind of materials that would be met with in the course of the work. The borer would put his iron tubes into the earth, and down he would pierce through sand, gravel, clay, stone, coal, for, say, five or six miles ; then he would probably come to a soft or molten mass of matter, and through that for upwards of 7000 miles, until crunch, crunch, would the iron go again, as it encountered the hard substances near the surface on the other side ; and then after more labour for a few miles, daylight would be let in from the opposite side of the globe, and the tube completed. The result of such an operation would be to show us that we live upon an enormous shell of rock, a few miles in thickness, and that within this shell, or crust, we have good reason to suppose is one mass of soft, seething, bubbling matter, several thousands of miles in diameter.
Whatever substances are found composing the crust of the earth are by geologists called rocks.
It has been found that the variety of appearance which the earth's surface presents is due very much to the character and formation of the rocks which lie beneath.
Various and gigantic changes are also found to be constantly taking place on the earth's surface, by the silent action of the powers of nature. Thus the streams, the rains, and the snows are constantly wearing away the rocks into sand, which being carried along by the rivers and distributed upon their banks and at their mouths, forms, in the course of time, new land. This soil, after the lapse of ages, hardens again into rock, which may again turn to sand, and so repeat the process—from rock to sand, and from sand to rock.
It is found too that, while mountains are worn down in one place, they are thrown up in another. This wearing down and heaving up has been going on for many, many ages, long before mankind were upon the earth, and it will no doubt continue as long as the earth endures.
A journey by rail will often afford a very valuable opportunity for gaining an insight into the more important truths of geology, as there are few lines which do not, in some part of their course, dip more or less into the crust of the earth. Let us imagine ourselves taking such a journey. We see all manner of surface, pretty woodland with leafy trees, arable land with its wavy corn, pasture land dotted over with nodding kine and frisking lambs; now we come to the bleak moorland, and anon we are rattling along amongst hills and mountains. Suddenly we enter a tunnel. As we emerge, we examine its sides, and find them to consist of one solid mass of dull, heavy-looking matter, which is called unstratified rock. This is the foundation or original of almost all rock. It was produced by the agency of fire, in the interior of the earth, whence it has been thrown up. It is therefore called igneous rock, from the Latin ignis, fire. There are three varieties of igneous, or unstratified rock: the granitic, trappean, and volcanic.
Proceeding on our way, we presently arrive at a cutting through rocks which are formed by the agency of water. Observe the difference. The unstratified rock was one solid mass, or nearly so; but here the rock lies in layers piled one above the other, like a pile of books on a table, or the courses of bricks in the wall of a house. These are called stratified rocks, from the fact of their lying in strata or layers; and because they are formed by the action of water, they are also termed aqueous rocks, from the Latin aqua, water.
In this instance the layers are, perhaps, perfectly horizontal; but as we pass along, we shall come to a part where they are displayed in a sloping position. The cause of this
is, that at some period or other a lumbering mass of unstratified rock has been thrown up against them from below. Further on, they will be found to slope downwards in the opposite direction. In some instances they are found to stand on end; in others, only one part of the strata will be found to be out of the level, the adjoining strata not having apparently been affected by the shock. Those varieties of appearance result from the various degrees of violence or suddenness of the disturbing forces by which they are all produced.
Of the unstratified rocks, granite is the prettiest. It consists of numerous varieties, and is found in many places. Its beauty and durability render it a favourite building material, where these qualities are requisite. Peterhead granite has long been famous. Aberdeen is noted in all parts for its fine specimens. That town is almost entirely built of it, so abundant is it there. Pompey's pillar, in Egypt, is a very good specimen of fined grained granite ; and so is the statue of Memnon in the same country.
The Giant's Causeway, in Ireland, and the Islandof Staffa, in which is the world-famed Fingal's Cave, afford fine specimens of the trap rocks. The hard, durable greenstone, or whinstone, as the Scotch call it, is largely used for causeways in our streets ; and basalt, or any of the harder traps, is useful for breaking into small pieces for our macadamised roads.
The various stratified rocks invariably appear in one order. Certain of the rocks may be wanting in any particular spot, but the order of those which remain is never, on any account, reversed or changed. For the purpose of obtaining an idea of the varieties of stratified rocks
and of the order in which they are found, we will imagine ourselves to be descending a pit sunk at a place where they all appear. We will get into the bucket, for the cage is not yet placed.
q Be careful now ; keep clear of the chain. P Down we go, and how smoothly and pleasantly! Do not be afraid; for when fear comes, here, danger is nigh. n We are at the bottom, and after a rest m we will ascend. We are supposed to 1 be standing upon granite or some other of the unstratified family of rocks. We k are ready. Up we go. Shade the light, and we shall see all the rocks nicely. This is gneiss," the first of the stratified series, very like its parent, granite; but with a washed, watery look, unlike the sharp, well-defined fracture of any of the igneous rocks, Mica and talc schist are the next, then clay slates,' so useful for roofing and other purposes.
These formed the PRIMARY ROCKS of the early works on geology; but the name is now g disused.
Next are greywacke," sandy slates, f and the old red sandstone.' These used to be called the TRANSITION ROCKS.
Now we are at the mountain-lime e stone, and next come the coal measures with their abundant stores of fuel, ironstone, shale, etc., the most profitable a and important of all. These form the chief source of our greatness, being the mainspring of our enormous commerce. Fears are entertained that these important measures will soon become ex- b hausted in Britain, and that, with these gone our power must decline. Let us hope a not, but meanwhile exercise all care in