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a considerable time over the fire, a quantity of small scales may be perceived floating upon the surface of it; if the lead remain a long time upon the fire, the whole of it will be changed to these scales; they will become a fine powder; the powder of burnt metals, (for all except gold. and silver, may be burnt by long continued heat,) is called calx.
The plural of calx, is calces,
The calces of lead, prepared in one way, become red lead; prepared in another way, they become white lead.
The white paint which is put upon houses is a mixture of oil and white lead.
Metals and glass are brilliant; that is, they shine when they are in the light. The light passes through the glass; it is transparent. Light does not pass through the metal; it is
Metals are the heaviest substances which are known in the world. Take a piece of paper just as big as a dollar, in one hand, and a dollar in the other-which is the heaviest ? Metals are heavy.
Take a hammer, and a little piece of brickstrike the brick with the hammer-the brick flies into a thousand little particles. Take a piece of lead, beat it with the hammer, it spreads larger and larger, the longer it is beaten. This property of spreading under the hammer is malleability. A substance which spreads, when it is beaten, is malleable. The brick is not malleable, it is brittle. Lead is malleable. All metals are malleable. One name for a hammer, is mallet.
Metals can be drawn out to wire. Iron, and brass, and gold wire, are used for many purposes. When a lump of any substance can be drawn out into a string, it is ductile. Molasses, when it is boiled, becomes hard-a lump of it can be pulled out very long, and can be twisted, without breaking. In the same manner, a lump of gold, iron, or brass, can be drawn into wire. Gold can be drawn to a wire as fine as a hair.
Metals are ductile.
This sticking together of the parts of a substance is called cohesion, or tenacity. Sand has no tenacity, but gold has.
Metals will melt-a lump of wax, or of snow, will melt very quickly; it takes a longer time, and hotter fire, to melt metals, than to melt
Melting, is fusion.
Substances which melt are fusible. Some substances, when they are put into the fire, fall to powder, as wood, which falls to the powder called ashes. A substance which is changed by fire to powder, is calcined.
Metals are fusible.
A metal is a brilliant, opaque, heavy, malleable, ductile, and fusible mineral.
Metals are found in all countries. Some countries produce much greater quantities than others. Very little gold is found in Europe; Asia produces some, Africa more, and the gold mines of South America more than every other part of the world. There is a great deal of silver also in South America. The richest gold and silver mines are in Potosi, in the country of Peru.
Look at a silver dollar. Once that dollar was in the mine. Some people went thither and found the silver ore; they carried it to a large oven, called a furnace, where was a very hot fire. The fire melted the silver, which ran out from the other things mixed with it: they did not melt, so the silver was found by itself, pure. The pure silver is too soft to be used by itself, without the addition of some other metal to make it a little harder.
A small quantity of some other metal is added to the silver this is called alloy.
The metal used for money is carried to a place called the mint; there it is cut into small pieces and weighed. Every true dollar weighs exactly so much; every half dollar weighs half as much as a whole dollar.
The piece of silver intended for the dollar, or half dollar, is then stamped. Children have seen a watch seal, and have seen the figure upon the watch seal stamped upon sealing wax. In the same manner, the head of liberty, the letters, and the date of the year, which may be seen on eagles, dollars, and cents, are stamped upon them. Metal money, which has this stamp, is called coin. Bank notes are pieces of paper, used for money. Some people, who have a great quantity of money, put it together in a place called the bank: here they keep the coin. Coin is made of metals of different value —gold, silver, and copper. The American coin of the greatest value is the eagle, equivalent to ten dollars. It is a beautiful gold piece. Half
eagles, worth five dollars, are equally handsome. Dollars, half, and quarter dollars, and some coins of inferior value, in common use, are silver. Cents, each the hundreth of a dollar, are made of copper.
Metal money is heavy, and therefore inconvenient to carry about in large quantities. To remedy this inconvenience, bank notes were invented. A bank is a depository of money-a safe place to keep it in. The directors of the bank, instead of circulating the coin or property of the bank, issue, or send out, papers stamped with the value of money which belongs to the community.
Before money was invented, barter or exchange was practised. A man who wanted a new coat, and possessed a fleece from the back of his sheep, would give the wool to another man, in exchange for a coat, which the other man might possess; or, perhaps he would give two fleeces of wool for cloth enough to make one garment. A labouring man would take from another for whom he worked, food, or clothes. But this was not an easy mode of doing business, because persons might not like or want articles offered in exchange, so it was found best to use money; an article which every body agrees to value alike, and which every one will take, and every one will give, in exchange for things which are useful or agreeable,
Pure, means without mixture. We say clear brandy, when we mean brandy alone.
That is not right: it is pure brandy. Water
alone, in a glass, is pure water; brandy alone, is pure brandy; mix the brandy and water together-then, neither the brandy nor water are pure.
THE silver mines of South America belong to the Spaniards. People think if they have a great deal of money they shall be happy. Some money is necessary; we cannot have what we want, unless we can buy it. But if we have much more money than we need, we are not happier for it. We should take care of our money, and not spend it foolishly; but we should not love it too much-if we do, we shall become avaricious.
Some people believe if they have money, that it makes them of more importance than if they had it not; they believe that they need not try to make themselves agreeable; that they need not do any work; that they need not improve their minds, or learn any thing. Just so the people of Spain thought, when they had got a great quantity of gold from South America. They had so much money, they knew they could send to the poorer countries of Europe, and buy whatever they wanted.
They left off making what is necessary to wear; they left off cultivating the ground; and they left off improving their minds; and so, while all the people of other countries were growing more industrious, more learned, and more respectable, these rich Spaniards were