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It is interesting to note that, although just recovering from the war of 1812, the enterprising spirit of the merchants of Boston, in New England, was shown in the establishment, in 1823, scarce ten years after the lighting 5 of the Westminster Bridge, of the Boston Gas Light Company

The principle of gas lighting is easy to test. If you fill the bowl of a clay pipe with coal dust and plug it with clay,

and then put the bowl in the fire, the heat will drive out the 10 gas through the tube or stem, when it can be lit as it escapes.

On a large scale this is what is done at the gas-works. Coal is put into iron tubes, called retorts, the gas is driven off by heat, but in an impure state, being mixed with the vapors

of ammonia, tar and sulphur. It has to be put through a 15 process to rid it of impure matters which would dim its

light. The dull gas first made was hardly to be compared with the clear, colorless flame which illumines our houses

now.

Until the gas is wanted, it is stored in the gas-holder; 20 this holder is in two parts, the tank and the holder proper.

The tank is a pit in the shape of a cylinder, which is kept filled with water to prevent leakage of the gas. The holder is above the tank, and is filled with gas. Great care has to

be taken to prevent explosions. These do sometimes hap25 pen despite caution, shaking the district for miles around and often destroying life.

The wonderful powers of coal do not end at gas.

After the coal has been heated and the gas removed, there is left a black, porous, hard but brittle matter. This is 30 called coke. The gas companies sell it for fuel. It makes a quick, hot fire.

Other things produced by the manufacture of gas are hartshorn (ammonia), the strong-smelling coal-tar, from

which chemists make a great many beautiful colors known 35 as aniline dyes, and would you believe it? - the snow

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white, waxy substance called paraffine, which you have seen in the shape of candles.

Fuel for cooking, for warmth and for gas; fuel for smelting and forging metals; fuel for the arts of life which depend 5 upon boiling water, or upon dry heat; fuel for the engines

that drive our machines, mills and railway trains; fuel for other useful ends, too many to name, makes greater demands upon our coal-beds every year.

It is due to coal that we have steam-engines to begin 10 with, and that we can work them; that we can travel in a

few hours, by train, as far as we could travel in a week, not a hundred years ago; and take a voyage round the world in as few months as it once took years.

Everybody gains by the saving of time, for no one thinks 15 of saving time for the sake of wasting it, but to try to pro

duce more of the comforts and necessaries of life.

HELPS FOR STUDY

What led to coal gas being used for illuminating purposes?
For what other purposes is it used?
After the gas is removed from the coal, what is the product called?
What other products are obtained from coal?
What are “aniline dyes”?

PENS AND PENCILS

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I hope you have wiped the steel pen lying there on your desk, Nellie, for it was a great deal of work to make it. First, steel had to be rolled into thin sheets, cut into broad strips, heated, scoured and rolled again. Then each strip 5 had to be cut into blanks by a “cutting-out machine"; one or more holes were then stamped in each blank as well as the name of the maker. Next the blank was curved by stamping. The nibs had to be made by grinding on an

emery wheel; the slits made by peculiarly shaped chisel10 stampers. Then the pens were heated and scoured, and

placed in a revolving cylinder over a hot fire to give them that fine bronze color.

The lead pencil — do you take it up and wonder if that, too, has a history? It has. You would not think 15 that the part which is soft enough to “mark with” was a

kind of hardened coal, would you? It is, and it is called graphite or plumbago. It is a formation of coal from which all the gases have been driven by heat and pressure in the.

earth's crust. This graphite - black lead, we call it 20 sometimes, but it has nothing of metallic lead in it at all

is to boys and girls best known in the shape of that very useful article, the lead-pencil. But the chemist also uses it mixed with fire clay to make his crucibles; the engineer

uses it, finely powdered, to lubricate his machinery; and 25 the housekeeper uses it to polish her stoves to keep them from rusting.

There is not a very remote antiquity to the lead pencil. Some old parchments are known that were marked with lead ruling, but this must have been metallic lead. Le

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Moine, a writer of the year 1537, speaks of documents marked with graphite. Other writers have found papers which were evidently written with a piece of graphite inserted in the end of a stick. This shows the evolution 5 of the pencil, beginning with the use of a piece of graphite in connection with a stick.

The first pencil factory in America was founded by a school girl. There was a graphite mine in England at that

time, called the Barrowdale Mine. This school girl, from 10 somewhere, obtained some of these pieces, and anticipated

quite closely the pencil method of modern days. In some way she crushed the graphite, either with a hammer or a stone, and then employed gum, mixing the two together;

then she cut' an alder twig, dug the pulp out, and stuffed 15 the little alder cylinder full of this gum and graphite, and

thus produced the first lead pencil made in America. This took place in Danvers, Mass. Later a man by the name of Joseph W. Wade co-operated with this girl, and together

they made a number of lead pencils after the same 20 fashion.

After Mr. Wade came one Monroe, who made pencils first at Concord, Mass. They were fairly well made and answered the purpose, and became articles of commerce

at that time. About the same time the well-known liter25 ary man, Henry D. Thoreau, also of Concord, made pen

cils. Thoreau was an impecunious man, always poor, always in trouble for lack of ready money, sometimes in debt, and at one time was put in jail for not paying his

taxes. After he got his pencil business started, his friends 30 said: “Now there will be an end to Henry's poverty,” but

he dropped the work about as soon as he commenced it, and said he could not afford to spend his time on something that was already finished. If he could have seen

the lead pencils of to-day, he would not have thought that 35 he had worked out to its full completion the evolution of the lead pencil. This happened somewhere between 1820 and 1825, in Concord, Mass.

After him came a man by the name of Wood, who associated himself with Monroe. Wood was a very clever 5 fellow, an inventor and originator of clever machinery, and made some circular saws and knives, which he set to work on pencil making. In that way he anticipated some of the up-to-date features of the present pencil machinery.

Joseph Dixon, the founder of the Joseph Dixon Crucible 10 Company, about this time also made lead pencils after the

same system. In the Company's office there are some pencils that he made at that time. This practically completes the beginning of lead pencil making in the United States.

The Barrowdale Mine of England was the source 15 of the graphite, and the pieces of graphite quarried were

said to be in such form that they could be sawn and pressed into the wood. It could easily be foreseen, however, that pieces of this kind were not very numerous. It then oc

curred to a Frenchman by the name of Conte, to powder 20 the graphite and put it together with a binding material,

and he worked at it until he produced the graphite part of the pencil, substantially as it is made now. Not much, however, was done with it, either by Conte or by any other

Frenchman. The Germans then took it up, and while 25 this Frenchman was the originator of this system, to the

Germans belongs the credit of working it out and putting it into its present shape.

Concerning the coming of the Germans to America, Faber came first in 1861; the second American factory 30 was founded by what is known as the American Lead

Pencil Company. They started in 1864. In 1868, the Eagle Pencil Company transferred their interests here, and in 1872, the Dixon Company started."

The work of pencil-making is ingenious and attrac35 tive, and a nice exhibit of mechanical talent. The num

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