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and to the rank of lieutenant-colonel, and was decorated with the insignia of several orders. The independence of his principles caused him, in 1795, to send in his resignation. He accepted, in 1796, the office of manager of the theatre of Vienna, but was soon disgusted with a situation surrounded by embarrassments and unpleasant

ness.

On his return to Russia, in the spring of 1809, he was arrested on the frontier of the empire, and conducted to Kurgan, a pretty little town in Siberia, where he enjoyed full liberty, and he caused his pieces to be acted by the inhabitants. His numerous friends soon removed all impressions against him from the mind of the emperor, Paul I., and this monarch recalled him to court, and heaped favours upon him.

During the first years of Alexander's reign, Kotzebue travelled through France, Italy, and Germany, and afterwards, apparently, fixed his residence at Berlin, where he undertook the management of a journal; but after some years, having given cause of displeasure to Buonaparte, he retired thence to a small estate which he possessed in Esthonia. Admiration and hatred did not fail to pursue him even to his rural retreat. While the thunders of the Moniteur were hurled against him, the Agricultural Society of London sent him some farming implements, and the English admiral commanding in the Baltic permitted the present of peace to pass unmolested.

M. Kotzebue took part in the manifestoes and diplomatic notes of the Russian cabinet, published in 1811 and 1812. The emperor Alexander recompensed him by naming him at first, in 1813, consul-general at Konigsburgh; and afterwards, in 1816, by connecting him with the department of foreign affairs, as counsellor of state. In 1817 he received a commission to go to Germany, in order to send reports directly to the Emperor Alexander on the state of literature and public opinion in Germany.

This invidious office Kotzebue is said to have filled in a manner hostile to the freedom of his native land, and he was regarded with aversion by the liberals of Germany. His criticisms on the writings of certain authors, and his strictures on the conduct of the students of the German universities, highly exasperated them; and the feeling was so strong in the case of a young enthusiast named Sandt, that he went to Kotzebue's house, at Manheim, deliberately murdered him, and then gave himself up to justice.

1. What office did Kotzebue hold at the age of twenty?

2. What office did he accept in 1796 ?

3. To what place in Siberia was he sent by the Emperor Paul?

4. For what object was he sent to Germany by the Emperor Alexander?

5. What was the name of his assassin ?

LESSON LXXXIII. MARCH THE TWENTY-FOURTH.

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Of the Specific Gravity of Bodies.

Ir appears a natural question for youth to ask - why some bodies, as lead or iron, if thrown into water, sink; while others, as wood or cork, will swim? Informing them that bodies which are heavier than water, will sink in it, but those which are lighter will swim, may not be perfectly satisfactory, seeing that a pound of lead, a pound of water, and a pound of wood, are all equally heavy.

Now, though a pound of each of these substances be equally heavy, it should be remembered that their bulks or magnitudes are not equal. A pint of water weighs about a pound; but if the same pint measure were to be filled with lead, it would weigh eleven pounds; and, again, if filled with quicksilver, it would weigh fourteen pounds. Here, then, the water, the lead, and the quicksilver are equal in bulk, but very unequal in weight.

The specific gravity of bodies is denoted in chemical writings by comparing it with the specific gravity of pure water, in decimal figures, water being always considered as 1.000. Thus the specific gravity of the strongest sulphuric acid is 1.850, or nearly nine-tenths heavier than water. Iron is 7·650, or more than seven times and a half heavier than water; that is, a cubic inch of iron, if put into a scale, would require seven inches and a half of water to balance it; silver is 10·478; gold, 19.300; and platinum, 23.000, or twenty-three times heavier than water.

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The nations of antiquity were unacquainted with any method of ascertaining the specific gravity of bodies. singular event was the cause of its being discovered by Archimedes 200 years before Christ. Having reason to believe that an unprincipled goldsmith had greatly debased the golden crown of Hiero II., king of Syracuse, he was anxious to ascertain the fact, but was perplexed by not knowing how to effect it. However, one day while bathing, the difference in the weight of his own body when in the water and when out of it, gave him the idea that he might adopt that method for discovering the specific gravity of

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the king's crown; and it is related of him that he was so rejoiced at the discovery, that he leaped from the bath in an ecstasy, and ran through the streets of Syracuse, crying, "I have found it! I have found it!"

It would be a pleasing and not altogether an unprofitable employment to endeavour to recount the mathematical, philosophical, and chemical truths, which tend to promote the happiness and civilisation of man, and which the ancients were totally unacquainted with. It is absolutely necessary to understand the nature of specific gravity, to enable a person to analyze minerals, to examine the gases, and to perform a variety of other operations in chemistry. Besides, this knowledge will be of use in the common occurrences of life, and no one who wishes to have a general acquaintance with things ought to neglect to acquire it. For instance, suppose a person has a piece of silver plate which he suspects is alloyed more than it ought to be, a knowledge of specific gravity, and of the principles of bodies which sink in fluids, displacing so much of the fluid as is equal to their bulk, will enable him to ascertain its value with accuracy. He has only to weigh it in air, and then in water, and calculate from the difference in its weight when weighed in these two mediums. Thus, if it weighs 46 ounces in air, and only 41 ounces when weighed in water, its bulk of water is 4 ounces. Now, if 46 be divided by 41, the quotient will be 101; which shows that the piece of plate is 10 times as heavy as its bulk of water, which is about the specific gravity of standard silver; though pure silver is 10 times the specific gravity of water.

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1. What is the relative weight of a pint of water, a pint of lead, and the same of quicksilver?

2. In chemical writings how is the specific gravity of bodies ascertained?

3. What led to the discovery made by Archimedes ?

4. How would you ascertain whether a piece of silver plate was alloyed more than it ought to be?

LESSON LXXXIV.

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MARCH THE TWENTY-FIFTH.
The Hermit.

Ar the close of the day, when the hamlet is still,
And mortals the sweets of forgetfulness prove;
When nought but the torrent is heard on the hill,
And nought but the nightingale's song in the grove:

'Twas thus, by the cave of the mountain afar,

While his harp rung symphonious, a hermit began;
No more with himself, or with nature, at war,

He thought as a sage, though he felt as a man.
"Ah! why thus abandon'd to darkness and woe,
Why, lone Philomela, that languishing fall?
For spring shall return, and a lover bestow,
And sorrow no longer thy bosom enthral.
But, if pity inspire thee, renew the sad lay,

Mourn, sweetest complainer, man calls thee to mourn; O soothe him, whose pleasures like thine pass away : Full quickly they pass but they never return.

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"Now gliding remote on the verge of the sky,

The moon half extinguish'd her crescent displays: But lately I mark'd, when majestic on high

She shone, and the planets were lost in her blaze. Roll on, thou fair orb, and with gladness pursue The path that conducts thee to splendour again; But man's faded glory what change shall renew? Ah, fool! to exult in a glory so vain!

""Tis night, and the landscape is lovely no more;

I mourn, but, ye woodlands, I mourn not for you; For morn is approaching, your charms to restore, Perfumed with fresh fragrance, and glittering with dew: Nor yet for the ravage of winter I mourn;

Kind Nature the embryo blossom will save; But when shall spring visit the mouldering urn!

O when shall day dawn on the night of the grave! ""Twas thus, by the glare of false science betray'd, That leads, to bewilder, and dazzles, to blind, My thoughts wont to roam, from shade onward to shade, Destruction before me, and sorrow behind.

'O pity, great Father of Light,' then I cried,

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Thy creature who fain would not wander from thee; Lo, humbled in dust, I relinquish my pride;

From doubt and from darkness thou only canst free!'

“And darkness and doubt are now flying away,
No longer I roam in conjecture forlorn;
So breaks on the traveller, faint and astray,
The bright and the balmy effulgence of morn.
See Truth, Love, and Mercy, in triumph descending,
And Nature all glowing in Eden's first bloom!
On the cold cheek of Death smiles and roses are blending,
And beauty immortal awakes from the tomb."

OF HEAT AND COLD.

1. What bird is alluded to in the second stanza? 2. When is the moon said to be crescent-shaped ?

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LESSON LXXXV.-MARCH THE TWENTY-SIXTH.
Of Heat and Cold.

HEAT is the well-known sensation which we perceive on touching any substance whose temperature is higher than that of the human body. But in order to distinguish the matter of heat from the sensation which heat produces, chemists have agreed to call this matter CALORIC.

Caloric is everywhere indispensable to the existence of man. It is with fire that, in every country, he prepares his food, that he dissolves metals, vitrifies rocks, hardens clay, softens iron, and gives to all the productions of the earth the forms and combinations which his necessities require.

There are six sources from which caloric is procured; namely, from the sun's rays, by combustion, by percussion, by friction, by the mixture of different substances, and by means of electricity and galvanism. Of these the sun is the chief, and, probably, the original fountain which furnishes the earth with a regular supply, and renders it capable of supporting the animal and vegetable creations.

The sensation of heat and cold arises from the tendency which caloric has to diffuse itself equally amongst all substances that come in contact with it. If the hand be put upon a hot body, part of the caloric leaves the hot body, and enters the hand: this produces the sensation of heat. On the contrary, if the hand be put upon a cold body, part of the caloric contained in the hand leaves the hand to unite with the cold body: this produces the sensation of cold.

The effects of intense cold are remarkable. In Iceland and some other northern countries the thermometer frequently falls to zero, which is thirty-two degrees below the freezing point. At Hudson's Bay it has been known to sink fifty degrees lower. When stones or metals, which have been exposed to such degrees of cold, are touched by the tongue, or the softer parts of the human body, they absorb the heat from those parts with such rapidity, that the flesh becomes instantly frozen and mortified, and the principle of life in them is extinguished.

The quantity of heat given out in freezing occasions the progress of congelation to be extremely slow.

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