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and clear stream; such was the origin of glass.' The ancient Egyptians were certainly acquainted with the art of glassmaking. The earthenware beads found in some mummies have an outer coat of coloured glass; and among the ruins of Thebes, pieces of blue glass have been found. The manufacture of this important substance was long carried on at Alexandria, from which city the Romans were supplied with it; but before 'the time of Pliny it had been also introduced into Italy, France, and Spain. Glass utensils of various kinds have been found among the ruins of Herculaneum.

The use of this material in the glazing of windows is comparatively of modern date, at least in northern and western Europe. In 674, artists were brought to England from abroad to glaze the church windows at Wearmouth, in Durham; and even in the year 1567 this mode of keeping cold from dwellings was confined to the houses of the great, and was not universal even then. An entry made at that time respecting a survey of Alnwick Castle, the residence of the Duke of Northumberland, informs us that the glass casements were taken down

during the absence of the family to preserve them from accident. A hundred years after that date the use of window-glass was so small in Scotland, that only the upper rooms in the royal palaces were furnished with it, the lower parts of them being fitted with wooden shutters to admit or keep out the air.

Glass is formed by the fusion of flint, or flinty matter, such as fine sand, together with some alkali,-soda, potash, ammonia, or the like. The nature of the material produced will depend upon the quality and proportions of the ingredients employed; and thus an infinite variety of kinds of glass may be made. But in commerce five kinds only are recognised,first, bottle or coarse green glass; second, broad or coarse window-glass; third, crownglass, or the best window-glass; fourth, plate-glass, or glass of pure soda; fifth, flint-glass, or glass of lead.

Glass-houses are commonly constructed of brick, made in the form of a cone, varying from eighty to a hundred feet in diameter, and about as much in height. Furnaces of various kinds are erected in them, formed of such materials as are found best to resist the effects

of intense heat; and in these furnaces earthen pots or crucibles are placed, containing the substances—flint, alkali, etc.to be melted into glass. The size and shape of the crucibles vary according to the purpose for which they are intended, the usual dimensions being forty inches in depth, forty inches at the top, and thirty at the bottom. Those for bottle and crown glass are open at top, and are from three to four inches thick; those for flint-glass are covered at the top, and are made from two to three inches in thickness. Twelve crucibles are commonly placed, at equal distances from each other, round the circumference of the furnace, each being opposite to an opening in the wall, so that they may be charged, or filled, from time to time by the workman from without. The furnace may be approached on all sides, and ends in a chimney, the interior being an arched dome. When the glass has been melted and fashioned into the shape required, it is carried to another furnace or oven, not quite so hot as that necessary for fusion, and is suffered to remain there for several days; the heat being allowed to diminish by slow degrees until the fire is quite extin

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guished. This is called the annealing furnace, and the process of cooling the glass in it is called annealing. Unless this operation be carefully managed, the articles formed in the glasshouse can be of no use, because of the ease with which they are broken, the slightest scratch, or even a change of temperature, often causing them to fly in pieces.

It is impossible to describe here all the several processes employed in making the glass articles which in such great variety we daily see and use. If my readers should have at any time an opportunity to visit a glasshouse, let them by all means. embrace it. They will be surprised and delighted, particularly with the manufacture of flint-glass. There is perhaps no process in the arts which excites so much the admiration of a stranger, as that of fashioning this material into all the various objects of convenience and ornament for which it is employed. To see a substance, proverbially brittle, (in the state in which it is used by us,) blown with the human breath, pulled, twisted, cut, and then joined again with the greatest ease, never fails to strike with astonishment those who are

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RESISTING TEMPTATION.

A

LITTLE boy, five years old, was one day taken by his aunt to a druggist's shop, and there he observed an almond which had fallen from the counter on the seat just below it. He wished very much to take it, but, knowing it was not right to take that which belonged to another, he walked to the shop door. Still, however, he could not help thinking of the almond; he returned, looked at it, touched it with his finger, and then went away again. But Satan, who is always ready to tempt children as well as grown-up people to commit sin, put it

again into his head how nice the almond would be; it was only one, it could never be missed. So he walked again toward the seat; but, calling to mind the command of God, was heard to say to himself, "Thou shalt not steal," and immediately going away from the place of temptation, he remained at the door of the shop until his aunt was ready to go home with him.

Dear children, pray that you may be enabled to follow the example of this little boy.

"Resist the devil, and he will flee from you."

"Enter not into temptation."

THREE LITTLE GIRLS.

NE, two, three!
Don't you see?

All little girlies belong-
ing to me:

There's Katie so busy, and mischievous Lou,

And Elsie, who nothing as yet can do

But eat, and sleep, and kick out her feet,

And "make believe" angry and look very sweet;

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So many little wants to supply, So many times to sing "lullaby,"

"A terrible trouble," some folks So many little garments to sew,—

say;

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And the faces are always dirty, you

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