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Makers of Many Things.
by Eva March Tappan.
PREFACE
The four books of this series have been written not merely to provide agreeable reading matter for children, but to give them information.
When a child can look at a steel pen not simply as an article furnished by the city for his use, but rather as the result of many interesting processes, he has made a distinct growth in intelligence.
When he has begun to apprehend the fruitfulness of the earth, both above ground and below, and the best way in which its products may be utilized and carried to the places where they are needed, he has not only acquired a knowledge of many kinds of industrial life which may help him to choose his life-work wisely from among them, but he has learned the dependence of one person upon other persons, of one part of the world upon other parts, and the necessity of peaceful intercourse. Best of all, he has learned to see. Wordsworth's familiar lines say of a man whose eyes had not been opened,--
"A primrose by a river's brim A yellow primrose was to him, And it was nothing more."
These books are planned to show the children that there is "something more"; to broaden their horizon; to reveal to them what invention has accomplished and what wide room for invention still remains; to teach them that reward comes to the man who improves his output beyond the task of the moment; and that success is waiting, not for him who works because he must, but for him who works because he may.
Acknowledgment is due to the Diamond Match Company, Hood Rubber Company, S. D. Warren Paper Company, The Riverside Press, E. Faber, C. Howard Hunt Pen Company, Waltham Watch Company, Mark Cross Company, I. Prouty & Company, Cheney Brothers, and others, whose advice and criticism have been of most valuable aid in the preparation of this volume.
EVA MARCH TAPPAN.
I
THE LITTLE FRICTION MATCH
I remember being once upon a time ten miles from a store and one mile from a neighbor; the fire had gone out in the night, and the last match failed to blaze. We had no flint and steel. We were neither Indians nor Boy Scouts, and we did not know how to make a fire by twirling a stick. There was nothing to do but to trudge off through the snow to the neighbor a mile away and beg some matches. Then was the time when we appreciated the little match and thought with profound respect of the men who invented and perfected it.
It is a long way from the safe and reliable match of to-day back to the splinters that were soaked in chemicals and sold together with little bottles of sulphuric acid. The splinter was expected to blaze when dipped into the acid. Sometimes it did blaze, and sometimes it did not; but it was reasonably certain how the acid would behave, for it would always sputter and do its best to spoil some one's clothes.
Nevertheless, even such matches as these were regarded as a wonderful convenience, and were sold at five dollars a hundred. With the next kind of match that appeared, a piece of folded sandpaper was sold, and the buyer was told to pinch it hard and draw the match through the fold. These matches were amazingly cheap--eighty-four of them for only twenty-five cents! There have been all sorts of odd matches. One kind actually had a tiny gla.s.s ball at the end full of sulphuric acid. To light this, you had to pinch the ball and the acid that was thus let out acted upon the other chemicals on the match and kindled it--or was expected to kindle it, which was not always the same thing.
Making matches is a big business, even if one hundred of them are sold for a cent. It is estimated that on an average each person uses seven matches every day. To provide so many would require some seven hundred million matches a day in this country alone. It seems like a very simple matter to cut a splinter of wood, dip it into some chemicals, and pack it into a box for sale; and it would be simple if it were all done by hand, but the matches would also be irregular and extremely expensive. The way to make anything cheap and uniform is to manufacture it by machinery.
[Ill.u.s.tration: THE ENDLESS MATCH MACHINE
The match splints are set in tiny holes like pins in a pincus.h.i.+on, and the belt revolves, pa.s.sing their heads through various chemicals.]
The first step in making matches is to select some white-pine plank of good quality and cut it into blocks of the proper size. These are fed into a machine which sends sharp dies through them and thus cuts the match splints. Over the splint cutter a carrier chain is continuously moving, and into holes in this chain the ends of the match splints are forced at the rate of ten or twelve thousand a minute.
The splints remain in the chain for about an hour, and during this hour all sorts of things happen to them. First, they are dipped into hot paraffin wax, because this will light even more easily than wood.
As soon as the wax is dry, the industrious chain carries them over a dipping-roll covered with a layer consisting partly of glue and rosin.
Currents of air now play upon the splint, and in about ten minutes the glue and rosin on one end of it have hardened into a hard bulb. It is not a match yet by any means, for scratching it would not make it light. The phosphorus which is to make it into a match is on another dipping-roll. This is sesqui-sulphide of phosphorus. The common yellow phosphorus is poisonous, and workmen in match factories where it was used were in danger of suffering from a terrible disease of the jaw bone. At length it was discovered that sesqui-sulphide of phosphorus would make just as good matches and was harmless. Our largest match company held the patent giving them the exclusive right to certain processes by which the sesqui-sulphide was made; and this patent they generously gave up to the people of the United States.
After the splints have been dipped into the preparation of phosphorus, they are carried about on the chain vertically, horizontally, on the outside of some wheels and the inside of others, and through currents of air. Then they are turned over to a chain divided into sections which carries them to a packing-machine. This machine packs them into boxes, a certain number in each box, and they are slid down to girls who make the boxes into packages. These are put into wooden containers and are ready for sale.
As in most manufactures, these processes must be carried on with great care and exactness. The wood must be carefully selected and of straight grain, the dipping-rolls must be kept covered with a fresh supply of composition, and its depth must be always uniform. Even the currents of air in which the splints are dried must be just warm enough to dry them and just moist enough not to dry them too rapidly.
The old sulphur matches made in "card and block" can no longer be bought in this country; the safety match has taken their place. One kind of safety match has the phosphorus on the box and the other igniting substances on the match, so that the match will not light unless it is scratched on the box; but this kind has never been a favorite in the United States. The second kind, the one generally used, may be struck anywhere, but these matches are safe because even stepping upon one will not light it; it must be scratched.
A match is a little thing, but nothing else can do its work.
II
ABOUT INDIA RUBBER
When you pick a dandelion or a milkweed, a white sticky "milk" oozes out; and this looks just like the juice of the various sorts of trees, shrubs, and vines from which India rubber is made. The "rubber plant"
which has been such a favorite in houses is one of these; in India it becomes a large tree which has the peculiar habit of dropping down from its branches "bush-ropes," as they are called. These take root and become stout trunks. There is literally a "rubber belt" around the world, for nearly all rubber comes from the countries lying between the Tropic of Cancer and the Tropic of Capricorn. More than half of all that is brought to market is produced in the valley of the Amazon River; and some of this "Para rubber," as it is called, from the seaport whence it is s.h.i.+pped, is the best in the world.
[Ill.u.s.tration: _Courtesy General Rubber Co._
TAPPING RUBBER TREES IN SUMATRA
The plantation on which this photograph was taken has 45,000 acres of planted rubber trees, and employs 14,000 coolies.]
The juice or latex flows best about sunrise, and so the natives who collect it have to be early risers. They make little cuts in the bark of the tree, stick on with a bit of clay a tiny cup underneath each cut, and move on through the forest to the next tree. Sometimes they make narrow V-shaped cuts in the bark, one above another, but all coming into a perpendicular channel leading to the foot of the tree.
Later in the day the collectors empty the cups into great jugs and carry them to the camp.
When the rubber juice reaches the camp, it is poured into a great bowl. The men build a fire of sticks, and always add a great many palm nuts, which are oily and make a good deal of smoke. Over the fire they place an earthen jar shaped like a cone, but without top or bottom.
Now work begins. It is fortunate that it can be done in the open air, and that the man can sit on the windward side, for the smoke rises through the smaller hole thick and black and suffocating. The man takes a stick shaped like a paddle, dips it into the bowl, and holds it in the smoke and heat, turning it rapidly over and over till the water is nearly dried out of the rubber and it is no longer milky, but dark-colored. Then he dips this paddle in again and again. It grows heavier at each dipping, but he keeps on till he has five or six pounds of rubber. With a wet knife he cuts this off, making what are called "biscuits." After many years of this sort of work, some one found that by resting one end of a pole in a crotched stick and holding the other in his hand, a man could make a much larger biscuit.
For a long time people thought that rubber trees could not be cultivated. One difficulty in taking them away from their original home to plant is that the seeds are so rich in oil as to become rancid unusually soon. At length, however, a consignment of them was packed in openwork baskets between layers of dried wild banana leaves and slung up on deck in openwork crates so as to have plenty of air. By this means seven thousand healthy little plants were soon growing in England, and from there were carried to Ceylon and the East.
On the rubber plantations collecting juice from trees standing near together and in open ground is an altogether different matter from cutting a narrow path and forcing one's way through a South American or African jungle. The bark of the trees is cut in herringbone fas.h.i.+on. The collector simply slices a thin piece off the bark and at once milk begins to ooze out.
On the great plantations of the East the rubber is collected chiefly by Chinese and Indians. They are carefully taught just how to tap the trees. They begin four or five feet from the ground, and work down, cutting the thinnest possible slice at each visit. When they have almost reached the ground, they begin on the opposite side of the trunk; and by the time they have reached the ground on that side the bark on the first side has renewed itself. The latex is strained and mixed with some acid, usually acetic, in order to coagulate or thicken it. It is then run between rollers, hung in a drying house, and generally in a smokehouse.
The rubber arrives at the factory in bales or cases. First of all it must be thoroughly washed in order to get rid of sand or bits of leaves and wood. A machine called a "washer" does this work. It forces the rubber between grooved rolls which break it up; and as this is done under a spray of water, the rubber is much cleaner when it comes out. Another machine makes it still cleaner and forms it into long sheets about two feet wide.
Having thoroughly wet the rubber, the next step is to dry it thoroughly. The old way was to hang it up for several weeks. The new way is to cut it into strips, lay it upon steel trays, and place it in a vacuum dryer. This is kept hot, and whatever moisture is in the rubber is either evaporated or sucked out by a vacuum pump. It now pa.s.ses through another machine much like the washer, and is formed into sheets. The square threads from which elastic webbing is made may be cut from these sheets, though sometimes the sheet is wound on an iron drum, vulcanized by being put into hot water, lightly varnished with sh.e.l.lac to stiffen it, then wound on a wooden cylinder, and cut into square threads. Boiling these in caustic soda removes the sh.e.l.lac. To make round threads, softened rubber is forced through a die. Rubber bands are made by cementing a sheet of rubber into a tube and then cutting them off at whatever width may be desired. Toy balloons are made of such rubber. Two pieces are stamped out and joined by a particularly noisy machine, and then the balloon is blown out by compressed air.
Early in the nineteenth century it was known that rubber would keep out water, but it was sticky and unmanageable. After a while a Scotch chemist named McIntosh succeeded in dissolving rubber in naphtha and spreading it between two thicknesses of cloth. That is why his name is given to raincoats made in this way. Overshoes, too, were made of pure rubber poured over clay lasts which were broken after the rubber had dried. These overshoes were waterproof,--there was no denying that; but they were heavy and clumsy and shapeless. When they were taken off, they did not stand up, but promptly fell over. In hot weather they became so sticky that they had to be kept in the cellar; and in winter they became stiff and inelastic, but they never wore out. How to get rid of the undesirable qualities and not lose the desirable ones was the question. It was found out that if sulphur was mixed with rubber, the disagreeable stickiness would vanish; but the rubbers continued to melt and to freeze by turns until an American named Charles Goodyear discovered that if rubber mixed with sulphur was exposed to about 300 F. of heat for a number of hours, the rubber would remain elastic, but would not be sticky and would no longer be affected by heat or cold. This is why you often see the name Goodyear on the bottom of rubbers.
Rubber overshoes were improved at once. As they now are made, the rubber is mixed with sulphur, whiting, litharge, and several other substances. An honest firm will add only those materials that will be of service in making the rubber more easy to mould or will improve it in some way. Unfortunately, substances are often added, not for this purpose, but to increase the weight and apparent value of the articles. That is why some rubber overshoes, for instance, wear out so much faster than others.
To make an overshoe, the rubber is run through rollers and formed into thick sheets for soles and thinner sheets for uppers. Another machine coats with gum the cloth used for lining and stays. Rubber and rubber-lined cloth go to the cutting-room, where all the different parts of the shoes are cut out. They are then put together and varnished. While still on the last, they are dipped into a tank of varnish and vulcanized--a very simple matter now that Goodyear has shown us how, for they are merely left in large, thoroughly heated ovens for eight or ten hours. The rubber shoe or boot is now elastic, strong, waterproof, ready for any temperature, and so firmly cemented together with rubber cement that it is practically all in one piece.
During the last few years there have been frequent calls from various charities for old rubber overshoes, pieces of rubber hose, etc. These are of considerable value in rubber manufacturing. They are run through a machine which tears them to shreds, then through a sort of fanning-mill which blows away the bits of lining. Tiny pieces of iron may be present from nails or rivets; but these are easily removed by magnets. This "reclaimed" rubber is powdered and mixed with the new, and for some purposes the mixture answers very well. Imitation rubber has been made by heating oil of linseed, hemp, maize, etc., with sulphur; but no subst.i.tute for rubber is a success for all uses.
[Ill.u.s.tration: _Courtesy U. S. Tire Co._
HOW RUBBER GOES THROUGH THE FACTORY
Splitting Para biscuits, mixing the rubber, rolling the rubber fabric on cylinders, and building tires on the tire machines.]
There are many little conveniences made of rubber which we should greatly miss, such as the little tips put into pencil ends for erasing pencil marks. These are made by filling a mould with rubber. Rubber corks are made in much the same manner. Tips for the legs of chairs are made in a two-piece mould larger at the bottom than at the top, and with a plunger that nearly fits the small end. Often on chair tips and in the cup-shaped eraser that goes over the ends of some pencils you can see the "fin," as the gla.s.sworkers call it, where the two pieces of the mould did not exactly fit. Rubber cannot be melted and cast in moulds like iron, but it can be gently heated and softened, and then pressed into a mould. Rubber stamps are made in this way. The making of rubber heels and soles is now a large industry; hose for watering and for vacuum and Westinghouse brakes is made in increasing quant.i.ties. The making of rubber tires for automobiles and carriages is an important industry. The enormous and increasing use of electricity requires much use of rubber as an insulator. Rubber gloves will protect an electrical workman from shock and a surgeon from infection. Rubber beds and cus.h.i.+ons filled with air are a great comfort in illness. Rubber has great and important uses; but we should perhaps miss quite as much the little comforts and conveniences which it has made possible.
Rubber and gutta-percha are not the same substance by any means.