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A similar phenomena is observable in the manner in which a country blacksmith lights his fire. He takes a piece of cold iron, which we suppose to measure a cubic inch, and hammers it rapidly on his anvil, until he compresses the particles so as to measure but ninety-nine hundredths of a cubic inch. Thus the latent heat of the one-hundredth compressed, becomes present heat to the ninetynine hundredth remaining; and it is when thus hot that he ignites a match with which he lights his fire.

The Indian performs a similar operation, when by the rubbing of two pieces of wood on each other he causes them to take fire. The simple theory of their operation is, that if we examine the surface of the wood with a powerful microscope, we find it to contain millions of infinitesimal cells. All these cells are filled with globules of air; and at each rubbing, each globule gives out its latent heat, which heat is received by the wood, and each cell re-fills with a new portion of air, which at the next rub gives out its portion; and thus the accumulation of these quantities of heat causes the wood to take fire; proving that latent heat becomes present whenever you rob it of its sleeping-place. The grinding of a knife on a grindstone, and the consequent stream of fire, is due to the compression of the ultimate particles of metal, abraded from the knife, the compression of which particles causes sufficient of the latent heat of the metal to become present heat, to render the infinitesimal portions red hot, and consequently visible. So great was the liberation of latent heat in ERICCSSON's caloric engine that the cylinder was melted and the machine thereby rendered useless.

'Some substances are capable of receiving present heat, and 'putting it to sleep,' or rendering it latent. Ice registers thirty-two degrees by the thermometer; and if a vessel filled with ice be placed over a fire until it be melted, it will still register thirty-two degrees. If a similar quantity of fuel to that used to melt this ice to water be burned under it after it is water, it will raise it to two hundred and twelve degrees, or cause it to boil. The question naturally occurs, what became of the first quantity of heat liberated from the first charge of wood burned? The answer is simply, it was absorbed by the ice as it expanded in becoming water; and will be given out again whenever the same portion of water be re-converted into ice.

'When two fluids of different specific gravities are mixed together, they will not make the bulk of both, although they contain the weight of both. If sulphuric acid, which is much heavier than water, and boils at six hundred and twenty degrees Farenheit, be mixed with water which will boil at two hundred and twelve degrees Farenheit, you will have in bulk as a result only three-quarters of the measurement of both. This decrease of bulk lessons the capacity of the mass to contain heat; and thus the latent heat of the missing quarter becomes present heat, and is sensible to the touch. Sometimes it is difficult to heat metals sufficiently to cause them to become fluid or to melt; when two metals of different specific gravities are heated together, they combine, and the latent heat given off, from the consequent diminution of bulk, assists to keep the mass fluid.

Thus

platina, which cannot be melted by the hottest blast-furnace, melts readily if heated in contact with a very minute portion of lead.

'Another class of proofs of the existence of latent heat embraces the facts connected with the capacities of bodies for heat, by enlarging their bulk; for, from the same course of reasoning that latent becomes present heat, by diminishing the bulk of a body, present heat will be received and rendered latent by any body, the bulk of which is increased. If we wet the head with alcohol, and then fan it rapidly, the alcohol becomes an aëriform body, and consequently increases in bulk some two thousand times. Its capacity for heat is thereby increased; and it seizes it from the nearest hot object, the head, thus rendering the head cool. And in this manner local fevers are often removed.

In the East Indies it is common to form ice by evaporating ether from the surface of water. The great increase of bulk from the ether so suddenly robs the heat from the water as to render it ice. This experiment can be readily made in this manner: Fill the bulb at the lower end of a thermometer-tube with water; wrap tow on the outside, then dip it in ether, move it rapidly in the atmosphere for a minute, tear off the tow, and the bulb will be found to contain a ball of ice. In hot climates water is cooled for domestic use in unglazed earthen vessels, called monkeys.' They are partially porous, and thus a minute portion of the water is continually oozing through to the surface. If these vessels be placed in a draft of air, or swung on the end of a rope attached to a tall tree, the evaporation of water from the outside will abstract the heat from the contents of the vessel, and render it palatably cool. Water in a pitcher, placed in a window where there is a strong draft of air, and surrounded with a cloth kept continually wet, will become cool. A 'refreshing shower' is a very common phrase; and it arises from the fact, that when Nature is covered with a minute film of water, its evaporation cools all surrounding objects.'

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THERE is a fiend who taketh angel guise,

And by some dark Promethean art would seem
From Heaven's empyrean throne to snatch a beam
Of holiness, wherewith to dazzle mortal eyes;
Pure, like the evening star of summer skies,
When softly mirrored on the placid stream,
His eye in truth uplit, one fain would deem,
With the meek light of love; and from his tongue
There flows a silver tone, more glozing far
Than that which tempted EVE the trees among.'
Within rage, envy, malice, hatred are ;

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Unmask thee, wretch! thy reign must cease ere long,

And on thy forehead let the world descry,
Branded in fire, thy name- - HYPOCRISY !

New-York, May, 1846.

B. W. C. MASSETT.

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With the aid of the law,

And (telling some friends what was the design meant,)
He and his lawyer drew up an assignment.
A queer little instrument, that, by the way,
Describing what debts one proposes to pay,
And mentioning who are to suffer delay:
That is, take a promise at very long day,
For twenty per cent. of the face of their notes,
Thus slily dividing the sheep from the goats.

But now all his troubles

Have vanished like bubbles;

He's a gentleman, made on the very best plan,
Is rich, and of course a respectable man;'
Has a house and a farm, and much money invested,
Is deeply in rail-roads and banks interested;

Is called, in his dealings, a very correct man,

Is Deacon in church, and what 's more, a Select-man.
You'd be edified quite with his sanctified air,
His very grave face, and exceeding white hair:
He is weak in the hams and thin in the chest,
His years may be sixty-and that will attest
That he 's well on the road to his 'haven of rest.'

That blessing of life,

His adorable wife,

Links to her end of the rope a great clatter-
Forever it pours, like the rain, patter, patter;
And though I should like the good woman to flatter,
Yet I'm forced to admit the amount of her chatter,
And that it abounds with irrelevant matter.

Nobody but her

Could mutter and splutter

In a way the weak nerves of her good man to flutter:
But still the dear little woman means well,
Though, obliged as I am the truth here to tell,
Her husband quite often has wished her in-
I had like to have said it! but if you can spell,

Well!

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The wide-spreading ends of which, that is to say, his toes,
Snugly ensconsced in a pair of green slippers,

Whose prows were as sharp as a Baltimore clipper's,
While a tune like a bugle began then to play his nose.
He was barely composed,
And hardly had dosed,

When a thundering knock,

Like a great church clock,

Came banging away at the front hall-door,
And nipped in the bud an incipient snore;
And ere he could get from the chair to the floor,
Instead of one knock there were twenty or more,
Till they rolled on his ear like a cataract's roar.

He rose in a hurry,
His wits in a flurry,

Expecting to find at least half a score
Of customers waiting his nod at the door;
So he opened it wide,

And there, outside,

Stood a single tall fellow of six feet two!
A burly young giant he was to the view,
Who only drawled out, through his nose, How d'
Then said, as he leisurely walked to the fire,

6

ye

Here's one of the clocks that you sold to me, 'Squire. You do n't recollect? Well, I'd have you to know

You warranted this here correctly to go;

But at times it 's too fast, and at times it 's too slow;
As I bought it of you,

And it do n't go true,

But is up to all sorts of fantastical tricks, it
Returns, and won't suit, no way you can fix it.'

SOLOMON TERRY

Was in a quandary ;

But ere he could open his mouth to reply,
(Of course with a lie,)

There came rushing in,

With horrible din,

One after another, a concourse of men!
Terrible fellows! He didn't know when

65

VOL. XXVII.

do?"

He had seen such a desperate visaged array,
And all talking at once in a shocking bad way;
While every one bore, dangling over his shoulder,
What made the heart sink of the frightened beholder;
In short, what gave him this terrible shock,

Was the fact that each man brought with him a clock!

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