Part 20
The transmission makes it possible to reverse the car. It also enables the driver to go into high-speed gear when on level roads and low-speed gear for starting and for pulling hills.]
[Illustration: Double-drop pressed steel frame.
The frame on which the car is built.]
[Illustration: Addition of semi-elliptic and three-fourths-elliptic springs to frame.
Large springs are placed at the front and rear of the frame. They make the car ride smoothly.]
[Illustration: Adding the front axle.]
[Illustration: READY FOR THE WHEELS
Showing addition of full-floating rear axle.]
[Illustration: Completed engine and transmission is next fastened to the frame and connected to the rear axle by the drive shaft.]
[Illustration: Showing addition of gasoline tank and gas lead to carburetor.]
[Illustration: Showing how steering gear is connected.]
[Illustration: WHAT THE COMPLETED CHASSIS LOOKS LIKE
Wheels are next added to chassis.]
[Illustration: Completed chassis with radiator added.
The water which keeps the engine from getting too hot is pumped around the cylinders and then through the radiator. The wind blows through the little openings in the radiator, and cools off the water. Then the water is pumped around the cylinders again.]
[Illustration: The steps and fenders are next attached.]
[Illustration: THE MARVELLOUS GROWTH OF TWENTY YEARS
The finished car.]
[Illustration: GASOLINE AUTOMOBILE.
The first American-built automobile, now in Smithsonian Institute, Washington, D. C., where this photograph was taken. The rude carriage that was a curiosity twenty years ago and less--the vehicle that vied with the two-headed calf and the wild man of Borneo at the county fairs--was the beginning of the greatest transportation aid since the birth of civilization. Because of it our standards of living have become higher. It has broadened the horizon of all of us.
Built by Elwood Haynes, in Kokomo, Indiana, 1893-1894. Equipped with one-horse-power engine. Successful trial trip made at speed of six or seven miles an hour, July 4, 1894. Gift of Elwood Haynes, 1910. 262,135.]
[Illustration: When an automobile passed you twenty years ago.]
[Illustration: HOW AUTOMOBILES HAVE IMPROVED
LEFT SIDE VIEW
RIGHT SIDE VIEW
A new exhibit in the Smithsonian Institute, officially known as “Exhibit Number 56,860,” is attracting a great deal of attention from visitors to the National Museum. It consists of a complete Haynes six-cylinder unit power plant, and has been given a position at the side of the original Haynes “horseless carriage,” where the striking contrast shows the remarkable improvement that has been made in motor design and construction during the past twenty-two years.
The most important features of the power plant are shown clearly and comprehensively by having sections cut away from the various parts, so that the visitors to the Institute are enabled to see the mechanical construction, and the relation of the component devices.
On the right side of the engine, the intake and exhaust manifolds are shown in their natural position. A full vertical section of the Stromberg carburetor gives a good idea of how the gasoline is mixed with the air and supplied to the cylinders. The Leece-Neville generator has its casing cut away to give a view of the windings and cores. Numerous windows have been cut into the crankcase to disclose the crankshaft construction and the oil reservoir. The transmission gears are also shown in this manner.
Most of the electrical equipment is shown clearly on the left side of the motor. Here an interesting feature is the full vertical section of the American Simms high-tension dual magneto. A half section has been removed from the rear cylinder, and the piston as well, to give a glimpse of the interior construction. A large portion of the Leece-Neville starting motor casing has been cut away. The cover-plate on the switch controlling the starting motor has been replaced with a glass cover to display the method of completing the circuit from the battery to the motor. A skeleton selector switch is mounted at the rear of the transmission case, instead of its usual position on the steering wheel. The electric gear-shifting mechanism is made visible by using a glass plate for the top cover-plate on the transmission.]
Why Does the Heart Beat When the Brain Is Asleep?
Under ordinary conditions the heart beats are controlled by certain nerve cells which are located within the heart itself, and these cause the heart to beat even while the brain is asleep. This explains why the heart beats when the brain is asleep, and the fact that the brain when asleep does not exercise its functions, shows how necessary this arrangement and the control of ordinary heart beats is. If this were not so, we should not be able to live while asleep. It is just like the management of a great business in this sense. The general manager of a great business has control of the entire works, but there are occasions when he must be thinking of only one thing in connection with the business, and so he must have his organization so complete, that the parts which he cannot be thinking about at the time will do their work just the same. So he surrounds himself with competent assistants, who look after certain departments while he is busy or away or asleep, and if anything goes wrong while he is away, he calls on special forces to set things right. Now, the brain is the general manager of the whole body and has these nerve cells in the heart as a sort of assistant manager to look after the heart beats in ordinary conditions, and to keep the heart going while he is asleep. But, by reason of his office as general manager, the brain has a special way of sending orders to the heart through special nerves which run from the brain down each side of the neck to the heart. There are two pairs of these special nerves. One pair, if set in motion, will make the heart beat faster, and the other pair will make the heart beat more slowly.
Why Do Our Hearts Beat Faster When We Are Running?
When you start running, the brain knows at once that your legs and other parts of the body will need more blood to keep them going, and so the brain sends down orders through his special nerves which make the heart beat faster, to get busy, and they do. Then when you stop running, your heart is beating faster than necessary--there is really an oversupply of blood being pumped through your system for the time being, and that makes you uncomfortable, until the brain sends word through the other set of nerves to the heart to slow down the heart beat. It is better to stop running gradually, to give the heart a chance to get back to its normal beat gradually also.
Why Do I Get Out of Breath When Running?
This is also caused by your brain in its efforts to keep up your supply of good blood. We breathe to take air into the lungs, where the blood which has once been through the arteries and comes back on its return trip to the heart, is exposed to the air in the lungs, before going back into the heart. The air which we take into our lungs purifies the once used blood and makes it into good blood again. When you run the heart pumps blood into your arteries faster to enable you to run. Thus also, the arteries send much more blood back to the heart through the veins, and this must be purified by the lungs before going back into the heart. To attend to purifying this extra amount of spoiled blood the lungs need more air, and thus you are made to breathe in more air for the purpose. Unless you are in good training--your wind in good condition as we say--it is almost impossible for you to supply the lungs with enough air for the purpose, but whether you can do it or not, the lungs call upon you for more air, and cause you to try to get it, and that is what makes you get out of breath.
Why Does My Heart Beat Faster When I Am Scared?
The natural tendency of a scared creature is to run or fly. The effect of being scared has the same effect on the brain that your starting to run has. The brain is always as quick as you are, and knowing that when you are scared your actual or natural inclination is to run, it is merely getting you in shape so that you can move or run fast.
Why Does Cold Make Our Hands Blue?
Your hands appear blue when cold because the veins which are near the surface are filled with impure blood which is purplish in color. Your hands become cold because there is not sufficient circulation of warm red blood going on to keep them warm. The blood in circulating through your body sends warm red blood through the arteries, and this is returned to the heart through the lungs by way of the veins. The veins carry only used-up blood or what is left of the good red blood when the arteries are through with it. Its color is a purplish blue.
When your hands are blue it means that circulation of good red blood has practically stopped--the red blood is not flowing from the heart through the arteries in sufficient quantity and there is no color in the arteries, as the blood from the arteries has practically all gone into the veins. The veins are full to purplish blue blood, and this makes the hands look blue, because there are a great many veins in the hands close to the surface.
Why Do I Get Red in the Face?
Now, when you rub your cold blue hands together, you start the circulation going again, and that brings the red blood into the arteries, giving you the healthy red color again. When you run hard to get red in the face because you are causing an unusual amount of red blood to flow through your whole body by your violent exercise. Some people with an extraordinary amount of circulation are red in the face all the time. This is because of the presence of a great deal of blood in the arteries, or because the walls of their arteries are so much thinner than others that the red blood shows through more easily.
Is Yawning Infectious?
Yawning is infectious to the extent that other habits are. The desire to yawn which comes to us when we see some one else does so comes under the heading of suggestion. The power of suggestion is greater than many of us realize. We are great imitators of each other. When one of us is downhearted, we are apt to become happy and glad simply by being with other people who are happy and glad. If enough people one at a time tell a perfectly well man that he looks sick, he will actually feel ill, provided he does not suspect a game is being played on him. So a good actor carries his audience with him. He can make them laugh or cry almost at will, and if he yawns, his audience will begin yawning.
Often, however, there is no acting connected with the yawning of the first person. Then the yawn is caused because the person is not sending enough good air into the lungs for purifying the blood, and the yawn is only nature’s way of making us take an exceptionally deep breath of air in at one time. This lack of sufficient good air in the lungs may not be due to the poor breathing, but to the amount of bad air in the room. In such cases it is quite likely that other people in the room yawn when one of them starts it because they all begin to feel the need of more good air at about the same time.
What Makes Me Want to Stretch?
The necessity or desire to stretch comes to us because certain parts of the body are not receiving the proper amount of blood circulation and it is these parts that we stretch at such times. If you have ever been to a ball game, you know, of course, that it has become customary for the crowd, no matter how large, to stretch its legs and arms during the last half of the seventh inning. In fact, that has come to be a fixture at ball games and is universally known as the “stretch inning.” Now, it is not so much the result of a desire to encourage the home team as the natural following out of nature’s laws that originally started this practice. The end of the seventh inning at a ball game generally means that the crowd has been sitting quite still for the greater part of an hour and a half, just long enough for the circulation to become poor in parts of the body, and the custom of stretching at a ball game thus comes from the necessity of getting a little more speed into the action of the heart to increase the blood supply.
In other words, the stretching constitutes a mild form of exercise. You will notice the ball players themselves do not stretch themselves in the last half of the seventh inning. They are getting enough exercise without that.
It is natural, however, for us to stretch as we wake up from sleep after having lain quietly in one position for one or more hours. It is nature’s way of causing the heart to work faster.
What Happens When I Stretch?
What happens is simply this. When you stretch your arms and legs, you squeeze the arteries and veins which are a part of your arms and legs, much as happens when you pull on a piece of rubber tubing. The tubing becomes flat instead of perfectly round, and it is not so easy to send water through a flat tube as through a round one. Just so with the heart. It is the heart’s business to send blood through the arteries at all times, and when you make them flat the heart’s job becomes just a little harder, and it goes to work beating just a little faster to overcome this extra difficulty. By that time you are through stretching and the heart is busy pumping blood a little faster than ordinarily, and that is what makes you feel so good after you have stretched.
Why Can We Think of Only One Thing at a Time?
If you are asking the question intelligently, you must know that to think means to concentrate, and in that sense we can only think of one thing at a time, because it takes all of that part of the brain which is used for thinking for just one thing. To give close attention to any one subject means to turn the entire brain force practically in one direction. To let other things pass through the mind at the same time may appear not to interfere with the one thought, but they do, and our conclusions suffer accordingly.
You can be doing something with one part of your body, while engaged in thinking of one thing, but only such things as are more or less mechanical as the result of habit, such as walking, or moving the arms--things which the parts have done so often that actual attention by the brain is not absolutely essential. Take for instance, the fact that a man in deep thought on one subject will sometimes walk up and down the room or along the sidewalk. He can do this walking and still think concentratedly, but if he stubs his toe on the leg of a chair or on a rough place in the walk, his thought is broken, because the brain immediately takes itself out of the thought and pays its attention to the toe that was stubbed.
Why Do I Turn White When Scared?
Simply because, when you are scared or frightened, the blood almost leaves your face entirely. Under normal conditions, the red blood which is flowing through the arteries of your face, gives the face a reddish tinge, and your face becomes white when you are frightened, because then the blood leaves the face. It is quite singular, but when you are really frightened, whatever the cause may be, the human system receives such a shock that the heart just about stops beating all together. When your heart stops beating of course the flow of the blood from the heart stops and then there is no supply of fresh red blood coming through the arteries under the skin of your face. Therefore you look white--the color your face would be if no blood ever flowed through your arteries and veins. Some people have faces so white they look as though they were scared all the time. This is not because they have no blood flowing through the veins and arteries in their faces, but because their supply of blood is less than other peoples, and sometimes because the walls of their arteries and veins are much thicker than the average that the color of the blood does not show through. There are also many people who have so much blood in their systems all the time, and the walls of whose arteries are so thin, that they look at all times as though they might be blushing.
What Makes Me Blush?
Anything that will make your heart send an extra supply of blood into the arteries and veins which supply your face with blood, will make you blush. Embarrassment will do this. So will anger generally, although sometimes people get so angry that the blood is driven out of their faces. In this case they are so angry that their heart has stopped beating, practically.
What Occurs When We Think?
When we think the mind is acting on sensations; it is receiving, in conjunction with memories of sensations it has previously received. Sensations as they reach the mind arouse the mind to activity and, as soon as the sensation is received, the mind begins to compare the new sensation with sensations received at previous times, and by putting things together reaches a conclusion.
When you are thinking you are really trying to call upon memory to help you. You know the thought of one thing calls up another, and this leads to something else. This association of ideas is the faculty which enables us to think consecutively and accurately. It is the business of the mind to receive the sensations that enter it and arrange them in their proper places. That memory of past sensations is the important part of thinking, is proven by the fact that when we have forgotten a thing we are unable to think what it was.
Can Animals Think?
For this reason if animals have memory they should be able to think. It is now believed that many animals have to a certain extent the power to remember.
A dog will recognize his master even though he has not seen him for years. We might think he does this by his highly developed power of smell, but if his master has come from a direction opposite to that from which the dog first sees him, he could not have tracked him by his smell. A dog will recognize his master from quite a distance, so he must have to a certain extent the ability to remember or the power of association of ideas, which amounts to the same thing. Again, a horse that once belonged to the fire department, even though now hitched to a milk wagon, will have the impulse to run to the fire when he hears the fire gong. And an old war horse will prick up his ears as he used to when he hears the bugle call.
Why Do I Sneeze?
You sneeze sometimes when you look up at the sun or at a bright light. There does not seem to be any real good explanation of why looking at a bright light should make you sneeze. It is due to the connection there is between the nerves of the eyes and the nose. You generally blink if you look at a bright light suddenly, and the blinking process stirs the nerves inside of the nose to make you sneeze.
You know, of course, that the start of the sneeze is inside of your nose. The nose is, besides being the organ of smell, the channel through which we take air into the lungs, when we breathe properly. The nose is lined with membranes, back of which are a net of very small nerves which are extremely sensitive. The membranes are placed there to catch and hold the impure particles of matter which come into the nose when we take in a breath of air, and sneezing is only one effective way of cleaning out the nose. It is brought on only when some
## particularly difficult job of nose-cleaning has to be done. Pepper up
the nose will make you sneeze quickly, because pepper produces a very great irritation inside the nose, and the nose goes to work at once to get rid of it in the quickest possible manner as soon as the pepper comes in. Other things have the same effect. Sometimes a cold in the head causes you to sneeze. The sneeze in that event is merely nature’s effort to clean out the nose when other efforts have failed.
There are many suggestions for stopping a sneeze before it takes place, after you feel it coming on, such as putting the finger on each side of the nose, and many others. But a half sneeze does not remove the cause of the sneeze, so it is much better to sneeze it out, and many people enjoy the after effects of sneezing so much that they take snuff into the nose to produce it.
What Happens When I Swallow?
The muscles of your throat act in the form of a ring when food passes into your throat. The food does not drop directly into your stomach. In other words, the action is not quite the same as when you drop a stone out of the window. When you do the latter, the stone hits the sidewalk or whatever is below at the time, with a smash. It would hardly do to have our food drop into the stomach, so the muscles of the throat are arranged to contract in rings which push or squeeze the food downward, and the food is passed from one ring of muscles to the other. It is just like pushing a ball down into the foot of a stocking that is apparently too small for it to drop down. You put the ball in the top of the stocking and then by making a ring of your fingers around the stocking you can push the ball down. When you swallow, you start the muscles of your throat to making these rings. The upper ring squeezes the food on to the ring below it and so on down to the stomach.
What Makes the Lump Come In My Throat When I Cry?
The “lump” which comes up into your throat when you cry is caused by a sort of paralysis of the rings of muscles in your throat. The muscles of your throat can make these rings or waves upward also, but it is more difficult upward than downward--probably because of lack of practice, as we say. When you have put something into your stomach that makes you sick and causes you to vomit, the throat muscles take the matter from your stomach and bring it back to the mouth in the same way, except, of course, that this action begins at the bottom.