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Fossils.—The word fossil, which means any thing that may be dug out of the earth, used to be applied to all minerals ; but modern 'geologists have conveniently restricted its application to organized bodies contained in the loose or solid beds composing the crust of the globe, and, for the most part, 'petrified; that is, converted into stone. 3 Fossils are now always understood to be petrified remains of animals or plants, and we say, fossil shells, fossil bones, fossil trees, &c.

All the solid strata, most abundant in animal remains, are either limestones, or contain a large proportion of lime in their composition. Many thick beds of clay also abound in them ; but in that case, limestone, in some form or other, is generally associated with the clay. From this it has been inferred, and not without a strong semblance of probability, that animals have mainly contributed to the formation of many limestone strata, in the same way as we see them now at work forming vast limestone rocks in the coral reefs of the Pacific Ocean.

Some of the marine reptiles are so extraordinary, in point of form and 4 size, as to deserve a more particular notice. Of these monsters of the ancient seas, nine different genera have already been found entombed in the secondary strata, and of some of the genera, there are different species. They have been called suurians by geologists, from the resemblance they bear to the lizard tribe, saura being the Greek name for a lizard. A common green lizard is a tolerably good representation of the general form of these reptiles; but a crocodile, or alligator, gives a still better idea of them.

and furnished the clue for succeeding inquirers. 4. The largest, the iguanodon; is seventy feet long, immensely exceeding in size any lizard; as the fossil animals the megatherium and the mastodon, about eighteen feet long and twelve feet high. exceed any living animals.

GREECE. From the Peloponnesian War to the Death of .

Alexander. Not long after the close of the Peloponnesian war, the states of Greece became involved in another, which was generally called the sacred war. The people of Phocis had been sentenced by the Amphictyonic council to pay a heavy fine for ploughing a field which belonged to the temple of Apollo at Delphos.

Rather than pay the fine, the Phocians resolved to go to war. The people of Athens, Sparta, and Achaia assisted the Phocians. The Thebans, Locrians, and Thessalians, took the part of the Amphictyonic council; and Philip, king of Macedon, was solicited to fight op the same side.

Philip was ambitious and warlike. No sooner had he marched his army into Greece, than he determined to make himself ruler of the whole country.

The man that gave Philip more trouble than any other, was Demosthenes, an Athenian. He was one of the most eloquent orators that ever lived; and he uttered such terrible orations against Philip, that the Athenians were incited to resist him in battle. It is from these orations against the Macedonian king, that severe speeches have since been called philippics.

But the Athenians were beaten at Cheronea, in the year 338 before the Christian era. Thenceforward, Philip controlled the affairs of Greece, till his death.

The new king of Macedon, though only twenty years. old, was well worthy to sit on his father's throne. He was · Alexander, afterwards surnamed the Great. Young

1. Vide Root. 2. Alexander prophesied of, Daniel ii. 39, and viii. 5–8, 20; he was therefore the destroyer of the second of the four great empires, and the founder of the third. Alexander reached the river Indus, the boundary of his immense empire, and his fleet sailed down that river to the Indian ocean, and up the Persiau gulf to the Euphrates.

as he was, he had already given proofs of the valour which so soon made him conqueror of the world.

Alexander subdued the Grecian states in the course of one campaign. He was then declared generalissimo of the Greeks, and undertook a war against Persia. The army which he led against that country consisted of thirty-five thousand men.

He crossed the Hellespont, and marched through Asia Minor towards Persia. Before reaching its borders, he was met by the Persian king Darius, who had collected an immense army. Alexander defeated him, and killed a hundred and ten thousand of his soldiers.

Darius soon assembled a mightier army than before; he had now half a million of men. He advanced to battle in the midst of his troops, seated on a lofty chariot, which resembled a moving throne.

But when the Persians saw how boldly the Macedonian horsemen advanced, they took to flight. Darius had just time to gallop away from the battle. Shortly afterwards, he was slain by two of his own subjects.

When Persia was completely subdued, Alexander invaded India, now Hindoostan.

In the early part of his career, Alexander had shown many excellent and noble traits of character. But he met with such great and continual success in all his undertakings, that his disposition was ruined by it.

One of his worst deeds was the murder of Clitus, an old officer who had fought under king Philip, and who had once saved Alexander's life in battle.

After Alexander's return from India to Persia, while drinking at a banquet in Babylon, he was suddenly taken ill, and death soon conquered the conqueror. GEOGRAPHICAL.-Write the names of the rivers of Greece, and of the towns which

stand on them. Write the names of the cities and remarkable places which Alexander the Great

passed through in going from Macedon to the river Indus. CHRONOLOGICAL.-Death of Philip, king of Macedonia, B.C. 336.

Death of Alexander the Great, his son, B.c. 323.

MINERALOGY.

Metals. Metals are brilliant, opaque, malleable, ductile, and fusible minerals.

The ore of a metal is the state in which it is generally met with in the earth, when it is so mixed with stony or other earthy matters, as not to show its proper qualities as a metal. .

Money is mostly made of gold and silver. Gold and silver are both perfect metals, that is, they cannot be destroyed by fire. Other metals, if kept a considerable time in the fire, change by degrees into a powdery or scaly matter, called calx.

Gold has several other remarkable properties. It is the heaviest of all metals, except platina. It is between nineteen and twenty times as heavy as an equal bulk of water. This weight is a ready means of discovering counterfeit gold coin from genuine ; for as gold must be adulterated with something much lighter than itself, a false coin, if of the same weight with the true, will be sensibly a larger. Gold is also the most 3 ductile of all metals.

As to the weight of silver, it is nearly one-half less than that of gold, being only eleven times heavier than water.

Quicksilver is a very different thing, and one of the most singular of the metal kind, as it is found in a fluid state at the 4 temperature of the atmosphere. It is one of the heaviest of metals, being about fifteen times heavier than water.

Copper is not a very heavy metal, being not quite nine times the weight of water. It is ductile, bearing to be rolled or hammered out to a very thin plate, and also to be drawn out to a fine wire. Verdigris is the

rust of copper, produced by the 'acid of grapes. Another great use of copper is as an ingredient in mixed metals, such as bell-metal, cannon-metal, and particularly brass.

Brass is converted to its yellow colour by means of another metallic substance, named zinc or spelter, the natural colour of which is white. A kind of brown stone, called calamine, is an ore of zinc. By filling a pot with layers of powdered calamine and charcoal, placed alternately with copper, and applying a pretty strong heat, the zinc is driven in vapours out of the calamine, and penetrates the copper, changing it into brass. It thus gains a fine gold-like colour, and becomes harder, easier to melt, and less liable to rust.

Lead is a coarse, heavy metal, found in several kinds of soils and stones. It is rather heavier than silver. Being easily oxidized, it increases in weight in the open air ; the

lead of churches frequently grows both in bulk and weight. · Iron is both very hard and very elastic; it is fusible and malleable, and may be softened by heating it often in the fire; it is hardened by extinguishing it in water.

Tin is a whitish metal, softer than silver and harder than lead; it is found both in lead and in silver mines. The greatest part of the tin consumed in Europe is procured from the mines of Cornwall and Devonshire, Camden supposes the abundance of tin in these two provinces to have given the name Britain to the whole country. The basis of pewter is tin, which is made by mixing at the rate of a hundred pounds of tin with fifteen of lead, and six pounds of brass.

to Vide Root. 2. The golden crown of Dionysius of Syracuse, was by this proved to have been adulterated; when placed in water it displaced more water than the same weight of pure gold. 3. Its ductility is so great, that a wire of gold may be drawn much finer than a human hair; and its malleability such, that it may be beaten until it will take fourteen millions of gold leaves to make the thickness of a leaf of common paper; whereas fourteen million sheets of paper placed on each other, would be three-quarters of a mile in thickness. 4. It freezes, and may then be beaten into plates, or drawn into wire like silver.

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