Geography - Suggestions For Lessons
( Originally Published 1915 )
WHAT is a mountain? (Show a picture.) It is a very high hill. Very few hills in Ontario are high enough to be called mountains. How high must a hill be before it may be called a mountain? There is no fixed rule for using the term mountain. What is called a mountain in one part of the country would simply be called a hill in another. For example, in some localities a hill about 500 feet high is called a mountain; in other localities, it would need to be over 1,000 feet high to be considered as such. When we speak of the height of a mountain we mean its elevation above the level of the sea. Explain. Some mountains are so low and their slopes are so gentle that one may climb to their tops without much trouble. Others are so high and their sides are so steep that it is difficult and Often impossible to reach their tops. The height of the highest mountain in the world is about five and one-half miles. Their tops may rise far above the clouds and are often hidden by them.
Examine as many pictures of mountains as you can find. What shape is the top of a mountain? It has many shapes—sometimes rounded, but often irregular. The top of a mountain that is much higher than the country about it is called a peak. What is the colour of the high mountain tops seen in pictures? Why are they white? They are covered with snow and ice. About two miles above us the atmosphere is so cold that snow will not melt. This is why very high mountain tops are always buried in snow and ice. A large mass of this snow and ice sometimes becomes loosened and slides down the mountain side causing great damage. This is called an avalanche.
What name is given to a row of mountains? These ranges, or chains, are sometimes hundreds of miles in length. Why does such a mountain range make a good watershed, or divide? What becomes of the rain that falls upon a mountain range? Which side of the range will have the greater rainfall, the windward or the leeward side? Why? In what ways does a mountain range hinder trade and travel? Where is the best place for crossing a mountain range? What name is given to such a crossing place? It is called a pass. Why was this name given to it? Why do railways always cross mountains through these passes?
Of what materials are mountains composed? Rock when exposed to the weather gradually crumbles away. What name is given to powdered rock? What becomes of the soil that is thus formed? Most of it is washed away and leaves the rocks bare; part of it covers the sides of the mountain farther down. This makes it possible for forests to grow on mountain sides. Do you see these forests in the pictures? Why can not trees grow on very high mountain tops?
Metals, such as gold, silver, iron, etc., are usually found in rocks. Why are these metals so often found in mountainous countries? Why do fewer people live in mountainous countries than in lowland countries? How do mountaineers make their living? Do they cultivate the land much? Why not? They hunt, pasture sheep, work in mines, etc. What name is given to men who hunt? To those who care for sheep? To those who work in mines? Name some wild animals that live in the mountains. Why do many people go to the mountains for their health? Give reasons why most people find it more pleasant as well as more profitable to live in the valleys rather than up among the mountains?
Make black-board sketches and sand and clay models of mountain, mountain range, pass, and valleys. Use -chalk dust to illustrate the snow-capped peaks.
Make an examination of a brook near the school. Where does the water come from? Is there a spring, or a swamp, or a tile-drain in the neighbourhood? If so examine it carefully to find out what contribution, if any, it makes to the water-supply of the brook. In what direction is the brook flowing? Why does it flow in this direction? What is meant by the source of the brook? What is its mouth? What evidence can you find that the brook is growing larger as it flows along? What name is given to the smaller streams that flow into it? What is the name given to the land bordering each side of the brook? Which is the right bank? The left bank? The bed, or channel, of the brook is the land between the banks and over which the water flows. Why does a larger stream dig out a deeper channel for itself than a smaller stream does? The larger stream is stronger and can do more work.
Is the current flowing at a uniform rate of speed? Test by throwing pieces of wood or leaves upon the water. Why is the flow faster in some places than in others? What kind of bottom has the brook where the current is slow? Why is it covered with mud or fine sand? In
what parts of the stream is the bottom covered with coarse gravel or stones? Account for this. Why is the water muddy after a heavy rainfall? Where did the mud come from? Why does it settle to the bottom where the cur-rent is slow rather than where it is swifter? If there is a pond in the neighbourhood, compare the colour of the water flowing into it after a rainfall with that of the water flowing over the dam. What becomes of much of the mud that is carried into the pond? If this were to continue for many, many years, what would probably be the fate of the pond? Show how swamps may be formed by natural ponds filling up with soil.
When the brook bends, what part of the current has the most speed? Test to find out. What is the effect of this upon the bank? Why is it being worn away? What kind of banks are worn away more rapidly, grassy banks or banks that are bare? Why? Find places where trees or bushes help to protect the banks. How do they do this? Explain why the brook tends to become more winding as the banks are worn away by the bending current.
Construct a paddle-wheel. Hold the wheel so that the ends of the paddles are in the flowing water. What makes the wheel turn? What useful work can moving water do? How? Why are dams built across streams? Note that many mills, factories, and electric power plants are operated by falling water. Mention other ways in which streams are useful to man. They drain the country of surplus water, supply water for man and beast, irrigate the land, furnish food fish and fur-bearing animals, and, if large enough, form a water-way for ships. By picture and description appeal to the pupil's imagination, in order that he may acquire definite notions of the great rivers at a distance.
A RIVER BASIN
It is of the greatest importance that the pupils should have a definite notion of river basin. This may be obtained by means of a few simple experiments and observations, followed by the study of a local stream.
Place an empty basin or pan out-of-doors during a rainfall, and note:
(a) That the water afterward found in the basin was supplied by the rain—there was no other source of supply.
(b) That the only rain-water that entered the basin fell within the limits of its rim.
Have the pupils observe the roof of the school-house during a rainfall. By means of questions, guide their observations until the following facts are established :
(a) That the ridge or watershed of the roof separates its two slopes and thus determines the direction in which the rain-water must flow.
(b) That at the foot of the sloping roof there is a drain (eaves trough) to carry away the water.
(c) That the water flows from the higher end to the lower end of this drain trough.
Next, the pupils should, if possible, observe a small, neighbouring stream whose basin is limited and therefore suitable for study. After they have carefully observed the stream and its slopes, help them to discover and to trace the watershed, or divide. Tell them that the land inclosed within this watershed and drained by the stream is called its basin. Refer to the experiment of the pan or basin to bring out the two points of resemblance between the two basins with respect to the rainfall. Then emphasize the drainage idea by referring to the conditions observed in connection with the school-house roof and by showing that somewhat similar conditions exist in the basin of the stream.
Where does the stream get its supply of water? Why does the stream flow along so steadily day after day? The explanation of these phenomena is somewhat difficult to understand at this stage. Observations show that the sources of water-supply are swamps, springs, and drains. These are fed by the rain and the snow that fall within the limits of the basin. Fill a large sponge with water to saturation and place it upon a slanting board. Water continues to flow from it for some time. This illustration will help the pupils to understand how swamps, springs, and drains provide a continuous water-supply even when it is not raining. A swamp is very much like a huge sponge filled with water.
These observations must be supplemented by verbal descriptions, pictures, black-board sketches, sand-table work, etc., until the essential features common to river basins are understood by the pupils.
The sand-table exercise may be carried on by the pupils as follows : Cover the surface of the sand-table with white paper and spread a quantity of slightly moist sand over it. Arrange the sand to represent the river basin with its watershed. Trace the courses of the brook and its tributaries. The white paper showing through the sand will show these courses very plainly.
The essential features referred to above may be summarized as follows :
(a) The river basin is contained within a watershed, or divide, which separates it from neighbouring basins.
(b) The river drains the whole tract of country embraced within the basin.
(c) An extensive river basin may have as many smaller basins within it as the river has branch streams.
(d) The land surface of the river basin slopes down to the river from both sides. The river flows along between slopes to its outlet, or mouth, which is at the lower part of the basin.
(e) The river has its source in springs, swamps, etc. These receive their water-supply wholly from the rain and snow that fall within the limits of the basin.
What becomes of all the water that rivers are carrying away? If you could float along upon the river in a little boat for days and days, you would finally reach the ocean. Let us learn a few interesting things about it.
Examine a picture of the ocean as it appears from the shore. Tell what you see. What colour is the water? It is a greenish-blue, but when there are clouds over it, it looks dark and gloomy. Find a picture of the ocean in a storm. What do you see? What happens to the waves when they strike the shore? Why is it dangerous for ships to be near the shore when a storm is raging? How are sailors warned of their danger in the darkness of night? What are harbours? Of what use are they?
How large is the ocean? It is thousands of miles long and in places thousands of miles wide. Many men have actually sailed on it all the way around the world. How deep is the ocean? Most parts of it near the land are shallow, but far out from shore it is in many places two miles deep, and in some places four or five miles deep.
As there are so very many rivers flowing into the ocean, why does it not fill up and overflow its banks? It cannot do this because most of the rain-drops that fall from the clouds in all parts of the world come from the ocean. You will learn about this in another lesson.
Is the water of the ocean fresh or salt? How would you account for the ocean being salt? Nearly all soils and rocks contain salt of different kinds. Some of it gets into the rivers and is carried away to the ocean. To learn how the water of the ocean became salt, try the following experiment : Fill a saucer with water in which some salt has been dissolved. Taste the water. Set the saucer where it will be exposed to the outside air for a day or two when the weather is warm. What became of the water? Did the salt disappear too? What proof have you that it did not? The water in the ocean is much like the water in the saucer in one respect. Great quantities of it disappear into the air to help to form clouds and rain-drops. The salt that the rivers carried to the ocean is left there, making its water salty. Indeed, it is so salt that no one would think of drinking it even if he were dying of thirst.
Why do some people go to the sea-shore in summer time? How do the people at these summer resorts pass the time? They walk upon the sandy beach, breathe the fresh air, and bathe in the cool, salt water.
What name is given to the land bordering on a pond or lake or sea? It is given different names, such as coast, or shore. Examine the shores of a pond or lake. Usually they are not straight but are more or less curved or bent. If there is no pond or lake near by, examine the pools by the roadside or in a field after a heavy rainfall. (A physical geography chart of land and water will greatly help here in imparting correct notions. Such a chart should be placed in every school.)
What do you call this point of land that juts out into the water? It is a cape. Find other capes. Here is another but larger mass of land jutting out into the water. Note that it has a neck-like part joining it to the mainland. The large mass of land just beyond the neck is almost surrounded by water. What name is given to this land? It is a peninsula. The neck of land joining it to the mainland is called an isthmus. Find other peninsulas and isthmuses. What is the point of land at the end of the peninsula called? What is a cape? Look at that land out there in the water. How would you describe it? It has water all around it. What shall we call it? It is an island. If the peninsula were to become separated from the mainland by having its isthmus washed away, why would we have to change its name? What would it have to be named? Why? What is the chief difference between an island and a peninsula? What is an island? A peninsula? An isthmus? Find as many pictures as you can of islands and capes.
Now take your sand-table and reproduce the above land forms, using damp sand to represent the peninsulas, islands, etc., and white paper or glass to represent the water.
Deal similarly with such water forms as gulfs, bays, straits, etc.
Finally, by oral description and especially by pictures, try to get clear notions of these land and water forms as they exist in the ocean; there are the great capes, bays, islands, straits, etc., of the world.
Why do you like to fan yourself when you feel hot? Why does this make you feel cooler? When the face is hot, the air next to it becomes hot too. The breeze from the fan drives away the hot air and cooler air takes its place. If this is kept up for some time, you feel much more comfortable.
What is a calm day? Why do you feel so uncomfortable on a calm, hot day? If a breeze begins to blow on such a day, why are you likely to feel more comfortable? What effect has wind upon the weather? Winds usually make the weather cooler.
Wind is air in motion. (See lesson on "Winds", Form I.) What causes air to move? Let us try to find out. Strike two chalk brushes together over a hot stove. Why does the chalk dust rise to the ceiling? The heated air carries it up. What causes the heated air to rise? The heat of the stove causes it to rise. Heat, then, must have something to do with the movement of air. Think of other examples of heat causing air to rise. Steam from a cup of hot tea, cinders and smoke from a fire out-of-doors, etc. Watch the movement of smoke in a room where there is a lighted lamp. See how the smoke floats toward the lamp and then rises above it. Hold the palm of your hand at different heights above a cup of hot tea. Do likewise over a cup of cold water. What difference do you observe? Why do you feel heat above the hot tea and not above the cold water? The reason is that air is rising from the former but not from the latter. What takes the place of the heated air after it has risen from the stove? Try to find out by striking the chalk brushes together at the side of, and below the stove. Cooler air from the floor takes the place of the heated air; it quickly becomes warm and in turn rises. This action of the air continues as long as there is fire in the stove. Make a drawing on the black-board that will show the movement of air in a room, caused by the hot stove.
Raise the window a little at the bottom and lower it at the top. Test the air currents with the chalk brushes. What causes the cool draught (or wind) to enter below? Why does the warm air go out above? The reason is that the hot stove makes the air lighter, and therefore it rises to the top just as cork rises in water. At the same time the cooler and heavier air pushes in at the side to take the place of the heated air that has risen. In this way a current or movement of air is kept up.
Is there anything like this taking place on a large scale out-of-doors? What is it? The sun makes some places hotter than others. Over such places the heated air rises and the cooler air from neighbouring places flows along to take the place of the heated air. When we feel the cool air rushing by on its way to do this, we say the wind is blowing. In all parts of the world there is a movement of the air from colder to warmer regions. This movement of air over the earth is called wind.
Why are north winds usually cooler than south winds? What winds usually bring rain? Fair weather? When clouds cover the sky and the south wind blows, it is a sign of rain. After the rain ceases, the wind changes and becomes a north or a west wind, the clouds are blown away, and we have fine weather. Why is there little or no dew on a windy night? If the air is hotter over the land than over the lake, which way will the wind blow? On or near a large lake, why have we breezes blowing toward the lake in the mornings and from the lake in the evenings? At what time of a summer's day do we usually, have least wind? Where do people go in summer to get cool breezes? Why? What useful kinds of work can winds do?
By keeping a daily record of the direction of the wind and of the kind of weather- that it brings, you will be able to discover for -yourself which winds are most likely to cause fair weather and which rainy weather. You should be able, too, to read the thermometer and record the daily temperature.
(a) That, when a pan of water is set out-of-doors for a day or so, the water will disappear. What became of it? Why can you not see it in the air? What name is given to water that disappears into the air in this way? It is called vapour, and we say that the water has evaporated. If the pan is placed on a hot stove, the water will disappear more quickly. Why?
(b) That the water in a salt and water solution will evaporate, leaving the salt behind. (See lesson on "The Ocean".) What does this teach us?
(c) That ink-wells in a warm school-room, if left uncovered, will soon become dry. Why?
(d) That wet clothes hung on a line out-of-doors will soon become dry. Why?
(e) That the sun and the wind will soon dry up roads and fields after a rainfall. Why?
From these observations we learn that water may be changed into an invisible water vapour and that heat will hasten the process. This water vapour is continuously rising from the surface of every body of water exposed to the air. It is rising from the ocean, from all lakes and rivers, and even from the ground wherever it is damp. What a large amount of water there must be in the air although we do not see it !
Now, how does all this invisible water that is in the air get back to the earth? Perhaps the following observations may help you to answer this question :
(a) Have you ever observed on a warm summer day that the sides of a pitcher of cold water will "sweat"? Where did the water that collects on the outside of the pitcher come from? 'Why are you sure that it did not come from the inside of the pitcher? What has really happened is that the pitcher cooled the invisible water vapour in the air near it and caused it to form in drops on its cold sides. We say that the vapour condensed on the sides of the pitcher.
(b) Observe that the window panes of the kitchen are often covered in cool weather with water, especially on "wash" days. Why? The invisible vapour from the boiler on the stove condensed on the windows.
(c) Observe the little white clouds formed by your "breath" on a frosty day. Why do you not see it on a warm day? It is not cold enough to condense the water vapour that is in the breath.
(d) Observe the "steam" that sometimes rises from a river, or pond, or lake. Under what weather conditions do you see it? It rises only when the air is colder than. the water. What name should we give to this so-called "steam"? We should call it fog, but it is really a cloud.
What do the above observations teach? They teach:
(a) That invisible water vapour floating about in the air may be changed back into water by coming in contact with a cold surface. The formation of dew may be thus explained. The earth after sunset cools faster than the air. This cooled earth cools the water vapour in the air next to the earth, and consequently water condenses upon the cold grass, stones, etc., just as it condensed upon the cold pitcher or upon the cold window pane. On very cold nights this water vapour freezes on grass, stones, etc., and forms white frost. True frost is not frozen dew.
(b) That warm winds sometimes carry the water vapour with which they are laden many miles, until it reaches a region where the air is very much colder. What happens to the water vapour when the cold air of this region chills it? It condenses into a great mass of very tiny water drops called a cloud. Sometimes these clouds form high up in the air. Why? It is because it is so cold up there. (See lesson on "Mountains ".) Why are clouds so often seen round the tops of high mountains?
Why is a cloud able to float in the air? The tiny drops of water of which the cloud is composed are so very, very small and so very, very light that they do not fall. Perhaps the following experiment may help you to under-stand this : Powder a piece of chalk until it is as fine as dust. Drop some of this dust into a dish of water. Why did it not sink to the bottom? The dust-like particles are so small and light that they float. Next, break up a lump of chalk into pieces about the size of peas and drop them into the water. What happens to them? Why did they sink? What does the experiment teach us? It teaches us that if the pieces of chalk are small enough, they will float in water, but if they are considerably larger, they will sink. Drops of water in the air act in a similar way. If they are small enough, they will float in the air; but, if they are large enough, they will fall to the earth.
When a cloud becomes still more chilled, what happens to its tiny drops of water? They unite to form larger drops and these fall to the earth as rain.
Snow is formed when the tiny droplets which form the cloud freeze. Each frozen droplet becomes a crystal of snow. When a large number of these tiny crystals cling together, they form a snowflake. The white mantle of snow that covers the earth after a snow-storm is really a frozen cloud.
Hail is probably frozen rain-drops or a mixture of rain and snow frozen.
Name the four seasons. Why do the seasons change four times a year? Let us try to find the reason by observing the sun's shadow during the year. For this purpose drive a stake into the ground in a sunny place. Have it about three feet high and wide enough to cast a distinct shadow. The observations should be carried out during the whole year and may be begun at any time.
Measure the length of the shadow of the stake at 9 a.m., at noon, and at 4 p.m. When is the shadow shortest? Why is it shorter at noon than at 9 a.m., or at 4 p.m.? When it is shortest the sun has reached the highest point in the sky for that day. It is at noon that shadows are always shortest. At what time of day is the sun hottest? Why? It is hottest then because the sun is most nearly overhead.
Just here you may, incidentally, make the following observations : When the shadow of the stake on any day is shortest, that is, when it is exactly 12 o'clock noon, lay the straight edge of a board along the shadow and, with a sharp-pointed stick or with a mixture of lime and water, mark a straight line on the ground. Note that every day at noon, no matter what the length of the shadow may be, it always lies along this line. What name may be given to this line? We may call it the "noon line ", another good name is "meridian line ", as the word meridian means mid-day. In what direction does this meridian line run? It is always a north and south line. Whenever the end of the shadow reaches this line we know that it is noon without consulting the clock.
Is the sun at the same place in the sky at noon all the year round? Try to find out by watching the shadow cast by the stake. Suppose that we begin observations about September first. With a tape-line or yard-stick measure the shadow twice a month. Be sure that the measurement is taken always exactly at 12 o'clock noon. Keep a record of these measurements. Also keep a record of the number of hours and minutes between sunrise and sunset on the days on which you measure the shadow. Get the latter information from a good almanac and test its accuracy occasionally as you find opportunity.
If the day set for the observation is cloudy, take the first sunny day that follows. Note that a straight rod with one end placed at the end of the shadow and resting upon the top of the stake will always point directly to the sun.
What was the length of the shadow at the beginning of September? On September 21st? Mark the end of the shadow on September 21st by a peg driven into the ground. Why is the shadow growing longer? It must be because the sun is getting lower down in the sky. In what part of the sky is the sun at noon on September 21st? It is. on this date that the day and night are equal in length. It is for this reason that it is called an equinox and, as this is the time when autumn begins, it is called the autumn equinox. This is the real end of summer and the beginning-of autumn.
Continue making measurements at least twice a month as time passes. As the shadows are getting longer, what change is gradually taking place in the position of the sun? What change is taking place at the same time in the length of time that the sun is shining each day? What change is taking place in the weather? It is gradually getting colder. What is causing the weather to become colder? There are two reasons why the weather is becoming colder, namely : (a) The sun is gradually getting lower down in the sky and cannot give us as much heat as it did. (b) As the days are gradually getting shorter, we are getting less heat daily from the sun.
When is the shadow longest? On or about December 21st. Drive a peg into the ground to mark the end of the shadow. Note that the shadows have gradually been lengthening ever since you began your observations in September. When the shadows at noon are lengthening from day to day, it is a sign that winter is coming. December 21st is the shortest day in the year, and it is on this date that winter really begins. How long did autumn last? It lasted for three months—from September 21st to December 21st.
How do the shadows change after December 21st? They gradually become shorter. What corresponding change is taking place in the position of the sun in the sky? What change is also taking place in the time during which the sun is shining each day? When are the day and night again equal in length? On March 21st. This is called the spring equinox. Why? It is on this date that winter is said to end and spring to begin. How long has winter lasted? How does the length of shadow on March 21st compare with its length on September 21st? Why are the shadows the same length? The sun on its journey back has reached the same part of the sky it was in last September.
Note that, after this date, the shadows continue to shorten, and that the time during which the sun is shining each day also continues to lengthen. What change in the weather is taking place? It continues to get warmer and warmer. Why? Give two reasons. When the shadows at noon are shortening as the days go by, it is a sign that summer is coming. When is the shadow shortest? On or about June 21st. Drive a peg into the ground to mark the end of the shadow at this date. How many hours of sunshine are there on June 21st? This is the longest day in the year. Where is the sun at noon? It is the nearest overhead to us that it ever gets. It is on June 21st that spring ends and that summer begins. After this date the shadow begins to lengthen once more.
What season begins when the end of the shadow reaches the peg nearest the stake? The peg farthest away from the stake? What seasons begin when the end of the shadow reaches the middle peg? By using a straight rod, the corresponding positions of the sun in the sky on these dates are readily found.
Some of you may observe the shadow of the stake a few times during the summer holidays, noting the dates of observation and the lengths of the shadow. By doing this you will secure most useful records covering the entire year.
There is another factor influencing the changes in weather that should perhaps be referred to. It is very closely related to the two factors already mentioned. Why does the hottest weather come after the longest day of the year (June 21st) ? We have already learned that after March 21st the sun actually shines more than twelve hours each day. It follows, therefore, that the earth is receiving more heat in the daytime than it loses by cooling at night. This surplus heat is stored up in the earth and is gradually making the earth warmer. Hence, there is more of this surplus heat in the earth in July and in August than in June. The great heat that we feel during July and August is, therefore, owing to the heat from the direct rays of the sun, together with that given off from the heated earth. It is because of the heat from both these sources that July and August are the hottest months of the year.
In a similar way it can be shown that our coldest weather is after the shortest day in the year (December 21st). During January and February most ,of the heat of the sun's rays is used up in warming the cold earth; there is little radiation of heat to warm the air. Heat conditions, however, gradually improve as spring approaches.
The facts learned by the above observations may be summarized as follows :
(1) The longest day of direct sunlight is on June 21st; the shortest, on December 21st; day and night are equal in length on March 21st and on September 21st.
(2) Autumn, begins, on September 21st; winter on December 21st; spring on March 21st; and summer on June 21st. Each season is therefore three months in length.
(3) The sun's shadows gradually lengthen during summer and autumn, and shorten during winter and spring.
(4) It is just when the sun has reached its highest place in the sky that our summer begins, and it is just when it has reached its lowest place in the sky that our winter begins.
(5) Our seasons are therefore caused by the following related factors working together: (a) The sun gradually changing its place in the sky.
(b) The variation in the length of time during which the sun shines each day.
(c) The gradual warming and cooling of the earth.
VARIATION IN THE LENGTH OF DAY AND NIGHT
In connection with the observations of the shadows cast by the sun during the year, make the following con-current observations to determine why the length of day and night varies during the year :
On or about September 21st, at sunrise, stand at the shadow stake and observe the exact place on the horizon line where the sun first appears. Drive a peg into the ground a few feet distant from the stake and in the straight line between the stake and the rising sun. On the evening of the same day make a similar observation as to the setting sun. The noon-time position of the sun in the sky can be readily found (see page 71). The three principal positions of the sun in the sky are thus deter-mined and permanently marked. Ask a pupil to stand at the stake and with arm extended trace with the forefinger the arc described by the sun in its apparent journey from sunrise to sunset.
Repeat the observations on or about December 21st, March 21st, and June 21st; and mark permanently the points of sunrise and sunset.
At the close of these observations, require the pupils in review to trace, as described above, the three arcs, namely, (a) the arc of June 21st, (b) the arc of September 21st and March 21st, and (c) the arc of December 21st. This should present no difficulty, as the sunrise, noon, and sunset positions of the sun on these dates have been permanently marked by means of the pegs.
If these instructions are carefully carried out, the following facts should become quite intelligible to the class :
(a) That, on or about June 21st, sunrise and sunset take place farthest north, that therefore the arc marking the pathway of the sun across the sky is longer, and hence that there are more hours of direct sunlight and consequently longer days and shorter nights, than at any other time of the year.
(b) That, on or about December 21st, sunrise and sunset take place farther south, that therefore the arc marking the pathway of the sun across the sky is shorter, and hence that there are fewer hours of direct sunlight and consequently shorter days and longer nights, than at any other time of the year.
(c) That, on or about September 21st, the points on the horizon line where the sun rises and sets correspond with those of March 21st and are intermediate between those of June 21st and December 21st, and that on these dates the sun shines twelve hours, thus making day and night equal.
NOTE.—In the above observations the best results will be obtained where the surface of the surrounding country is more or less level. If so desired, the sunrise and sun-set points on the horizon line may be marked by trees, buildings, or other objects in the distance. The explanation of the variation in the length of the arcs traced by the sun's apparent movement across the sky will be taught in the Junior Grade of Form IV.
THE EARTH AS A GLOBE
Its shape : Many years ago people believed that the earth was flat. What led them into this belief? What shape does the earth appear to have? Why does it appear to be flat? It is because we see but a very small part of it at a time. Place a piece of paper with a small hole in it upon an apple. You will observe that the small part of the surface of the apple seen through the hole appears to be flat although we know that the apple is round. What is the reason of this? What application has this to the earth and its shape?
What proof have we that the earth is round? Perhaps the most convincing proof to us is that people have journeyed around the earth. They have started from home and by going eastward for many days found that they finally reached home again coming from the west, and vice versa. You may go around a block in a town or township and come back to the starting-place, but to do so you will require to change your direction several times. In journeying around the earth, however, people keep the same general direction and get back to their starting-place. Take a ball or an apple and show how this may be done.
Show, by holding an object in front of a lighted lamp. that the shadow cast by the object is determined by its own shape. During an eclipse of the moon, watch the shadow that slowly creeps over its face. What shape has the edge of this shadow? It is the earth's shadow that you see on the face of the moon. (See diagram, page 10, Text-book.) Then what shape must the earth have? If we lived on the moon, the earth would be seen by us at nights as a very large moon.
Because the earth is a ball-like body or sphere, it is called a globe. Here is a small one that is kept in the school to show you just what shape the earth has.
Size : How large do you think the earth is? Measure an apple through its centre from one side to the other side. This is called its diameter. If it were possible for us to measure the diameter of the earth in a similar way, we should find it to be about 8,000 miles long. How many days would you require to travel this distance if your railway train covered 400 miles a day? The distance around the earth (its circumference) is about 25,000 miles. The earth is larger than the moon but much smaller than the sun.
Surface : Of what substance is the surface of the earth composed? It is composed of land and water. What do we mean by the term " land"? By this term we really mean rock. In what different forms is this rock found? It is found either as solid rock or as soil. The latter is simply rock that has been worn down to extremely fine pieces. There is about three times more water surface on the earth than there is land surface. The land is not evenly distributed over the face of the earth, but is found in great masses. What are these great masses of land called? What are the great divisions of water called?
On the globe at first and afterwards on wall maps, learn the names and relative positions of these continents and oceans.
Rural Ontario has been surveyed into units called townships. These are usually separated from one another by roads called town-lines or boundary roads. Each town-ship is further surveyed into concessions and lots. A con-cession is usually a strip of land extending from one end of the township to the other and is subdivided so as to form a row or tier of lots, each of these lots having the same frontage and containing the same area.
The roads in the township run both lengthways and crossways. The former usually run alongside the concessions and are known as concession roads or concession lines, or simply concessions. It will thus be seen that the term " concession " may be used in two senses. What are they? At convenient intervals roads cross the township at right angles to the concession roads; these are called side-roads. These concession roads and side-roads usually divide the township into blocks containing about 1,000 acres each. In most of the older townships there is, in some cases, only one concession between adjoining concession roads, in other cases, there are two concessions between. In the former case the lots are, as a rule, larger in area.
Both the concessions and the lots are numbered—the former from the town-line running along one side, and the latter from the town-line running along one end, of the township. By this arrangement it is a simple matter to find, or to describe, the location of any farm in the township.
NOTE.—The teacher should familiarize himself with the method of survey in the particular township in which his school is situated. A plan of the township may be drawn on the black-board and the pupils drilled until they can locate any farm, school, church, etc., that may be named. A plan of the local section on a scale large enough to allow the names of the farmers to be written on their respective lots will greatly aid in the under-standing of the township plan.
To teach representation by maps, try the following. Begin with a drawing or plan of the teacher's desk or table. This may be done thus : Place the table so that two of its edges run north and south. Place a large sheet of paper on it. Mark the centre of the paper and the directions, north, south, east, west. Now place several simple objects on the paper. Drill on the directions of these objects from the centre and from one another. Next, remove the objects, one by one, and mark in each case the place where it stood, either by writing the name on the paper or by making a simple outline, or picture, of the object. Drill upon the direction of these pictures from one another. The pupils will, in this way, learn that the sheet of paper is really a plan of the table, and that such a plan is called a map.
Take the paper off the table and hang it on the north wall of the school-room. Continue the drill on the directions of this map. The pupils will soon learn that the top of the map represents the north; the bottom, the south; the right-hand side, the east; and the left-hand side, the west.
After these relations have become fixed in their minds, require them to draw similar maps of their desks. They will readily see that it is impossible to draw all maps the full size of the objects. It is not advisable at this stage to trouble them with details of size and proportion. The important thing is that they learn what a map really is.
After drawing a plan, or map, of the desk, the pupils may attempt a map of the school-room. This should indicate the position of a few of the more prominent objects in the room, such as the stove, the teacher's desk, the door, etc. A map of the school grounds may be attempted next, followed later by maps of the section and of the township.
It is advisable that .these maps should be hung at first upon the north wall. After the different positions and directions have been drilled upon, the maps may be hung upon the other walls.
Be sure that the pupils understand the meaning of every mark or sign on the map. Every such mark, or sign, is like a word used in a sentence. Behind every word there must be an idea; otherwise the sentence can-not express thought. Marks, or signs, on the map, like words in a sentence, are of no use unless they help to relate ideas.