Illustrated Science for Boys and Girls Part 3

From the hot water the horns were changed to a series of similar caldrons at the other side of the room, filled with boiling oil. Paul noticed that when the workmen lifted the horns from these vats their appearance was greatly changed, being much less opaque, and considerably plastic, opening readily at the longitudinal cut made by the saw. As the horns were taken from the oil they were flattened by unrolling, and placed between strong iron clamps which were firmly screwed together, and put upon long tables in regular order.

"Now I begin to see how it is done," Paul said, though he was thinking all the time of questions that he would ask his uncle when there were no workmen by to overhear.

"The oil softens the horn," said Mr. Sanford, "and by placing it in this firm pressure and allowing it to remain till it becomes fixed, the whole structure is so much changed that it never rolls again. Some combs, you will notice, are of a whitish, opaque color, like the natural horn, while others have a smooth appearance, are of amber color, and almost transparent. The former are pressed between cold irons and placed in cold water, while the others are hot-pressed, it being 'cooked' in a few minutes. These plates of horn may be colored; and there are a great many 'tortoise-sh.e.l.l' combs and other goods sold which are only horn with a bit of color sprinkled upon it.

"The solid tips of the horns, and all the pieces that are worth anything cut off in making the combs, are made up into horn jewelry, chains, cigar-holders, knife-handles, b.u.t.tons, and toys of various kinds. These trinkets are generally colored more or less, and many a fashionable belle, I suppose, would be surprised to know the amount of money paid for odd bits of horn under higher sounding names. But the horn is tough and serviceable, at any rate, and that is more than can be said of many of the cheats we meet with in life."

The next room, in contrast with all they had pa.s.sed through previously, was neat and had no repulsive odors. Here the sheets of horn as they came from the presses were first cut by delicate circular saws into blanks of the exact size for the kind of combs to be made, after which they were run through a planer, which gave them the proper thickness.

"What do you mean by 'blanks'?" Paul asked, as his uncle used the term.

"You can look in the dictionary to find its exact meaning," was the answer. "But you will see what it is in practice at this machine."

[Ill.u.s.tration: "IN SOME REMOTE CORNER OF SPAIN."]

They stepped to another part of the room; and here Paul saw the "blanks"

placed in the cutting-machine standing over a hot furnace, where, after being softened by the heat, they were slowly moved along, while a pair of thin chisels danced up and down, cutting through the centre of the blank at each stroke. When it had pa.s.sed completely through, an a.s.sistant took the perforated blank and pulled it carefully apart, showing two combs, with the teeth interlaced. After separation they were again placed together to harden under pressure, when the final operations consisted of bevelling the teeth on wheels covered with sand-paper, rounding the backs, rounding and pointing the teeth; after which came the polishing, papering and putting in boxes.

"I suppose they go all over the country," said Paul as he glanced into the shipping-room.

"Much further than that," was the reply. "We never know how far they go; for the wholesale dealers, to whom the combs are shipped from the manufactory, send them into all the odd corners of the earth. Every little dealer must sell combs, and in the very nature of the business they frequently pa.s.s through a great many hands before reaching the user, so at the last price is many times what the makers received for them. I suppose it often happens that horns which have been sent thousands of miles to work up are returned to the very regions from which they came, in some other form, increased very many fold in value by their long journey. Or a horn may come from the remoter parts of South America to be wrought here in Ma.s.sachusetts, and then be shipped from point to point till it reaches some remote corner of Africa, Spain, or Siberia, as an article of barter. And even different parts of the same horn may be at the same moment decking the person of a New York dandy and unsnarling the tangled locks of a Russian Tchuktch."

While Paul was watching the deft fingers of the girls who filled the boxes and affixed the labels, his uncle stepped through a door communicating with the office, and soon returned with three elegant pocket-combs.

"One of these," he said, "represents a horn which came from _pampas_ of Buenos Ayres; this one, in the original, dashed over the boundless plains of Texas; and here is another, toughened by the hot, short summers and long, bitter winters of Canada. Take them with you in memory of this cheerless rainy day."

Paul could not help a little sigh as he thought again of the pleasures he had enjoyed in antic.i.p.ation; but still he answered bravely, "Thank you; never mind the rain, dear uncle. All the New York boys go off in the woods when they get away from home; but not many of them ever heard how combs are made, and I don't suppose a quarter of them even know what they are made of. I can tell them a thing or two when I get home."

IN THE GAS-WORKS.

Philip and Kitty were curled up together on the lounge in the library, reading Aldrich's "Story of a Bad Boy." It was fast growing dark in the corner where they were, for the sun had gone down some time before, but they were all absorbed in Tom Bailey's theatricals, and did not notice how heavy the shadows were getting around them. Papa came in by-and-by.

"Why, little folks, you'll spoil your eyes reading here; I'd better light the gas for you," and he took out a match from the box on the mantle.

"O, let me, please," cried Philip, jumping up and running to the burner.

So he took the match, and climbed up in a chair with it. Scr-a-tch! and the new-lit jet gave a glorified glare that illuminated everything in the room, from the j.a.panese vase on the corner bracket to the pattern of the rug before the open fire. But as Philip turned it off a little it grew quieter, and finally settled down into a steady, respectable flame.

Philip always begged to light the gas. It had not been long introduced in the little town where he lived, and the children thought it a very fine thing to have it brought into the house, and secretly pitied the boys and girls whose fathers had only kerosene lamps.

"Why can't you blow out gas, just as you do a kerosene light?" asked Kitty, presently, leaving the Bad Boy on the lounge, and watching the bright little crescent under the gla.s.s shade.

"Because," explained papa, "unless you shut it off by turning the little screw in the pipe, the gas will keep pouring out into the room all the time, and if it isn't disposed of by being burned up, it will mix with the air and make it poisonous to breathe. A man at the hotel here, a few nights ago, blew out the gas because he did not know any better, and was almost suffocated before he realized the trouble and opened his window."

"And where does the gas come from in the first place?" pursued Kitty.

"Why, from the gas-works, of course," said Philip in a very superior way, for he was a year the elder of the two. "That brick building over by Miller's Hill--don't you know--that we pa.s.s in going to Aunt Hester's."

"I know that as well as you do, Philip Lawrence," said Kitty with some dignity. "What I wanted to know was what it's made out of. What is it, papa?"

"Out of coal," said papa. "They put the coal in ovens and heat it till the gas it contains is separated from the other parts of the coal, and driven off by itself. Then it is purified and made ready for use."

"Out of coal? How funny! I wish I could see all about it," said Philip, looking more interested.

"And so do I wish I could," added Kitty.

"I don't see why it cannot be done," said papa. "If you really care to see it, and won't mind a few bad smells, I will ask Mr. Carter to-morrow morning, when he can take you around and explain things."

The next day when Mr. Carter was asked about it, he said, "O, come in any day you like. About three in the afternoon would be a good time, because we are always newly-filling the retorts then." This sounded very nice and imposing to the children, and at three the next afternoon they started out with papa. The gas-house certainly did smell very badly as they drew near it, and dainty Kitty sniffed in considerable disgust. Philip suggested that perhaps she had better not go in after all; he didn't believe girls ever did go into such places. And upon that Kitty valiantly declared she did not mind it a bit, and sternly set her face straight.

[Ill.u.s.tration: A RETORT.]

Mr. Carter met them at the door. "You are just in time to see the retorts opened," said he, and led the way directly into a large and very dingy room, along one side of which was built out a sort of huge iron cupboard with several little iron doors. The upper ones were closed tight, but some of the lower ones were open a crack, and a very bright fire could be seen inside. Everything around was dirty and gloomy, and these gleams of fire from the little iron doors made the place look weird and ghostly.

Long iron pipes reached from each of the upper doors up to one very large horizontal pipe or cylinder near the ceiling overhead. This cylinder ran the whole length of the room, and, at its farther end, joined another iron pipe which pa.s.sed through the wall.

"Those are the furnace-doors down below," said Mr. Carter to the children. "What you see burning inside of them is c.o.ke. c.o.ke is what is left of the coal after we have taken the gas and tar out of it. The upper doors open into the retorts, or ovens, that we fill every five hours with the coal from which we want to get gas. Each retort holds about two hundred pounds, and from that amount we get a thousand cubic feet of gas."

"Is it just common coal;" asked Kitty, "like what people burn in stoves?"

"Not exactly. It is a softer kind, containing more of a substance called hydrogen than the sorts that are generally used for fuel. Several different varieties are used: 'cherry,' 'cannel,' 'splint,' and so on, and they come from mines in different parts of England and Scotland, chiefly. Glasgow, Coventry and Newcastle send us a great deal."

Philip started as if a bright idea had struck him. "Is that what people mean when you're doing something there's no need of, and they say 'you're carrying coals to Newcastle?'"

"Yes. You see such an enterprise would be absurd. Just notice the man yonder with the long iron rod! He is going to open one of the retorts, take out the old coal--only it is now c.o.ke--and put in a fresh supply."

A workman in a grimy, leather ap.r.o.n loosened one of the retort doors, and held up a little torch. Immediately a great sheet of flame burst out, and then disappeared.

He took the door quite off, and there was a long, narrow oven with an arched top, containing a huge bed of red-hot coals.

"What a splendid place to pop corn!" exclaimed Kitty.

Papa laughed. "You would find it warm work," said he, "unless you'd a very long handle to your corn-popper." And Kitty thought so too, as she went nearer the fiery furnace.

"You see," said Mr. Carter, "these red-hot coals have been changed a great deal by the heat. They have given up all their gas and tar, and are themselves no longer coal, but _c.o.ke_. We shovel out this c.o.ke and use it as fuel in the furnaces down below to help heat up the next lot. Then new coal is put into the retorts, and they are closed up with iron plates, like that one lying ready on the ground."

"It's all muddy 'round the edge," observed Kitty.

"Yes, that paste of clay is to make it air-tight. The heat hardens the clay very quickly, so all the little cracks around the edge are plastered up. When the coal is shut up in the ovens, or retorts, the heat, as I just told you, divides it up into the different substances of which it is made; that is, into the c.o.ke which you have seen, a black, sticky liquid called tar, the illuminating gas, and more or less ammonia, sulphur, and other things that must be got rid of. Almost all these things are saved and used for one purpose or another, though they may be of no use to us here. If we have more c.o.ke than we ourselves need it is sold for fuel.

The coal-tar goes for roofing and making sidewalks, or sometimes (though you wouldn't think it possible, as you look at the sticky, bad-smelling, black stuff) in the manufacture of the most lovely dyes, like that which colored Miss Kitty's pink ribbon. The ammonia is used for medicine and all sorts of scientific preparations, in bleaching cloth, and in the printing of calicoes and cambrics."

"When the materials of the coal are separated as I told you in the retorts, most of the tar remains behind, and is drawn off; but some gets up the pipes. That large, horizontal cylinder is always nearly half full of it. The gas, which is very light, you know, rises through the upper pipes leading from the retorts, and bubbles up through the tar in the bottom of the cylinder. Then it pa.s.ses along the farther end of the cylinder, and into the condensing pipes."

He opened a door, and they went through into the next room. Here the large pipe which came through the wall of the room they had just left, led to a number of cl.u.s.ters of smaller pipes that were jointed and doubled back and forth upon each other, cob-house fashion.

"When the gas goes through these pipes," said Mr. Carter, "it gets pretty well cooled down, for the pipes are kept cold by having so great an amount of surface exposed to draughts of air around them. And when the gas is cooled the impurities are cooled too, so that many of them take a liquid form and can be drawn off."