Imágenes de páginas

Another workman places this sheet of paper, which is still quite damp, upon a thick piece of felt or very stout woollen substance. Upon the paper he places more felt, then a second sheet of paper, then one of felt, and so on.

When a large number of sheets have been laid upon each other, this pile is put under a press, and all the remaining water is pressed out. The sheets of felt are afterwards taken away, and the leaves, placed one on the top of the other, are again. put under the press. Then they are dried in a covered place, through which a current of air is passed, and the paper is made.

The paper which is used for writing must now be sized. If this were not done, the ink would not run easily over the paper, but would be drunk in by it. For this purpose it is plunged into a warm bath of alum and a sort of glue called “gelatine.” Then the sheets are again placed upon the felt, and once more pressed and dried.

When a very smooth and glossy surface is wished, the paper is glazed. This is

done by pressing it between highly polished rollers heated by steam.

The sheets are then put up into reams, each containing four hundred and eighty sheets.

A short time ago a new way of making very large sheets of paper was found out.

Two rollers are placed at a distance from each other, and a long band of canvas, its ends joined together after the fashion of a huge round-towel, is made to pass round them.

Upon this the pulp for the paper is poured. The water drains through the canvas, as in the other way of making the sheets it drained through the wire sieve, and the pulp becomes stiff. It is then passed between two other rollers covered with felt, and so the water is all pressed out.

The best paper is that which is made of hemp and linen rags. That which is made of cotton is the softest, but the mixture of the two materials makes a good firm paper. Paper has been made of straw, of bark, of wild hops, of nettles, and marsh mallow leaf,

of rushes, of the mulberry leaf, and of hay. It is also made now by tearing up waste paper, and treating it very much in the same way as the rags are treated.

Before people knew how paper could be made, they used shallow trays filled with wax ; they warmed the wax, and then wrote upon it with a sharp pointed piece of iron.

This was all very well to keep their writing for a time; but, you know, they could not have a separate frame of wax for every piece of writing; and so, before they could write again, they were obliged to melt the wax to obtain a fresh surface.

When people found that the bark of a plant called Papyrus could be used for writings, they thought it wonderful. It is because of this word papyrus that we call what we write on, paper.

Paper was not always so cheap as it is now; it is not more than fifty years ago, that children were taught to write with trays of sand and a pointer, because paper was too expensive to be used.






Ex-po-sed Va-pour
Fast-en-ing Ve-ge-ta-ble
Log-wood Yel-low.

INK. BLACK ink-you use black ink at school -is made of four things: Logwood, Sulphate of Iron, Gall-nuts, and Gum Arabic.

All these are beaten up together into a powder and boiled, and then strained off to leave a clear liquid. You would like to know where all these things come from.

“Gum Arabic,” or Arabian gum, is a juice or sap which is obtained by making cuts in a tree, called the Acacia, which grows in Arabia. Arabia is in Asia. You have read about Asia, and you

can find Arabia on the Map of Asia, close to Africa.

The gum runs from the tree in a thick clear liquid, into large vessels put on purpose to catch it, and, on being exposed to the air, becomes hard, when it is packed up, and sold to people in different countries. Gum, melted in hot water, is used for sticking papers together, for fastening thin pictures on cardboard, and for many other purposes.

We can get gum from the Fir tree, the Apricot tree, the Peach tree, and the Cherry tree; and all these trees grow in our own country; but their gum is not nearly so good as the Gum Arabic.

A “Gall-nut” is a round swelling, which is found upon the leaves and twigs of trees. It is made by a little insect pricking a hole to lay its eggs there. A great deal of the sap runs towards this wound made by the insect, and oozes out of it.

If you prick your finger badly, do you notice how much blood comes out of the small hole made ? much more

« AnteriorContinuar »