16. Fahrenheit thought he had found out the greatest degree of cold. He marked the thermometer one extremely cold day in Iceland, and put a nought, or zero, at that point. He had no idea of anything colder.

Now the ice-melting point is 32 above this zero. So 32° became our number for the melting-point of ice. The mercury can also

be brought down to zero by placing it in a mixture of snow and salt.

17. The melting point of ice is generally the same as the freezing point of water. This is why you see "Freezing Point," and not Ice-melting Point," marked at 32° on Fahrenheit's scale.

You remember that the space between the two fixed points on this scale is divided into 180 parts. Now 180 added to 32 make 212, which is the point at which water generally boils according to our long scale.

18. I will mention a few other points on this scale-Temperate Heat, which means neither very hot nor very cold, is marked 55°; Summer Heat, 76°; the natural warmth of our blood, or Blood Heat, is 98°. If you were to put the bulb of a thermometer under your tongue, you would find it always marked about 98%, whether you felt cold or hot.

19. Mercury is not the only liquid used for filling the tubes of thermometers. Very often the thin lively liquid called alcohol, or spirit of wine, is used. Now alcohol has

never yet been frozen; therefore it is very useful when great cold is to be marked.

There are also solid thermometers, and gas thermometers. But you are not likely to see much of these. The one you will see most frequently is that filled with mercury or alcohol, with Fahrenheit's scale at the side.

20. You must understand that a thermometer does not show you how much heat there is in a body. Its precise use is to compare the degrees of variation from hot to cold. A thermometer in a pail of hot water marks no higher than it does in a cupful of the same liquid.

21. By the aid of the thermometer travellers are enabled to compare the climates of different countries, and to give us, who stay at home, an exact idea of them. It is also necessary in the arts; it helps workmen to apply the exact amount of heat required in delicate operations, where the slightest excess might spoil the whole work.

1. Oh, the old, old clock, of the household stock, Was the brightest thing and neatest:

Its hands, though old, had a touch of gold, And its chime rang still the sweetest.

'Twas a monitor, too, though its words were

few,

Yet they lived, though nations altered; And its voice, still strong, warned old and young

When the voice of friendship faltered! Tick, tick, it said,-quick, quick, to bed,— For ten I've given warning;

Up, up, and go, or else, you know,

You'll never rise soon in the morning!

2. A friendly voice was that old, old clock, As it stood in the corner smiling,

And blessed the time with a merry chime, The wintry hours beguiling.

But a cross old voice was that tiresome clock, As it called at daybreak boldly,

When the dawn looked grey o'er the misty

way,

And the early air blew coldly;

Tick, tick, it said,-quick, out of bed,
For five I've given warning;

You'll never have health, you'll never get wealth,

Unless you're up soon in the morning.

3. Still hourly the sound goes round and round With a tone that ceases never;

While tears are shed for the bright days fled, And the old friends lost for ever!

Its heart beats on,-though hearts are gone That warmer beat and younger;

Its hands still move,-though hands we love Are clasped on earth no longer!

Tick, tick, it said,-to the churchyard bed,
The Grave hath given warning,—
Up, up, and rise, and look to the skies,
And prepare for a heavenly morning!

EARTHQUAKES AND VOLCANOES.

pre-em-in-ent, surpassing all | Cal-a-bri-a, a province to the

others.

e-mit, to throw out.

under.

extreme south of Italy. sub-terra - ne-an, ground.

1. A volcano is an opening made in the earth's crust by internal heat, which has forced melted or heated matter through the rent. An earthquake is the effect of the confined gases and vapours, produced by the heat upon the crust. When the volcano, therefore, gets vent, the earthquake always ceases; but the latter has generally been more destructive of life than the former.

2. Where one city has been destroyed by lava, like Herculaneum and Pompeii, twenty have been shaken down by the rocking and heaving of earthquakes. The records of ancient as well as modern times abound with examples of these tremendous catastrophes.

3. Pre-eminent on the list is the city of Antioch. Imagine the inhabitants of that great city, crowded with strangers on a festive occasion, suddenly arrested on a calm day by the earth heaving and rocking beneath their feet;

and in a few moments two hundred and fifty thousand of them are buried by falling houses, or the earth opening and swallowing them up.

4. Such was the scene which that city presented in the year 526; and several times before and since that period has the like calamity fallen upon it; and twenty, forty, and sixty thousand of its inhabitants have been destroyed at each time. In the year 17 A.D., no less than thirteen cities in Asia Minor were, in like manner, overwhelmed in a single night.

5. Think of the terrible destruction that came upon Lisbon in 1775. The fog had just cleared away on a warm, calm morning, when suddenly the subterranean thundering and heaving began; and in six minutes the city was a heap of ruins, and sixty thousand of the people were among the dead.

6. Hundreds had crowded upon a new quay surrounded by vessels. In a moment the earth opened beneath them, and the wharf, the vessels, and the crowd, went down into its bosom; the gulf closed, the sea rolled over the spot, and no vestige of wharf, vessels, or man ever floated to the surface.

7. How thrilling is the account left us by Kircher, who was near, of the destruction of Euphemia in Calabria, a city of about five thousand inhabitants, in the year 1638 ! "After some time," says he, "the violent heaving of the earthquake ceasing, I stood up,