Lessons in chalk modeling: The new method of map drawing

by Ida Cassa Heffron

SUGGESTIONS ON THE USE OF THE CHALK MODELED MAP OF NORTH AMERICA IN FOURTH AND FIFTH GRADES.

It is hoped that these suggestions will aid many teachers to realize that the Chalk Modeled maps signify much more than the simple fact of high and low land, or a representation of structural relief: that from them, together with suitable pictures showing typical scenes in different parts of the world, such valuable knowledge of the real surface of the earth may be gained by the pupil, as will enable him to appreciate the important relation sustained by man to his environment, and also to his fellow man.

Previous to the study of the map of North America, the pupil may be led to imagine the character of the country to the north, south, east and west of his own locality. He may travel in imagination across the continent to either ocean, and may study different sections of the country through pictures and from oral and written descriptions. Such sections should also be chalk modeled, showing the plateaus, mountain ranges, plains, valleys, arid and fertile regions.

These drawings should be large, sometimes extending the whole length of the blackboard from left to right, and drawn in a semi-conventionalized manner, that is, in a style that combines both landscape, and map drawing. This is an essential link between the two and should play an important part in the development of continental picturing: the motive being (in all this) to have the pupil mentally image the real continent, before the map or symbol is presented to him. With such preparation, when the chalk modeled map is placed before him he readily reads its surface contour.

He notes the great highlands, plateaus, and mountains, the plains, valleys, slopes, river basins, lakes and rivers.

He is then led to infer the character of soil, climate and vegetation—everything, indeed, that relates to man’s environment.

He is asked to locate the great forest regions that furnish material for shelter and articles of household use; to point out the areas best adapted to the growth of different kinds of food-plants, and also those that furnish material for clothing; to indicate the grazing lands where herds of cattle feed; the mining regions, where coal for fuel, iron, copper, silver, gold, and other valuable metals and minerals are found.

Information necessary to inferences is given at the moment required, such as altitudes, horizontal distances, latitude, etc. The pupil is also encouraged to read and acquire knowledge upon certain points for himself, that he may bring it to the class for the benefit of others.

(The following questions may have some value to the teacher in the further study of the map, but should by no means be used as a set form or method of questioning. They are only suggestions, given to those who may need them in assisting the pupil to think and reason for himself.)

His attention may be called to the triangular shape of the land mass, with its greatest elevation in the west. He may be told that its length is 5,700 and its greatest width 3,000 miles.

Questions may then be asked as follows: Into how many slopes or great drainage systems is the continent divided? Into what ocean do the waters of the long slope flow? Those of the short slope? Locate and give general direction of the continental axis. Trace this from Behring Strait to Isthmus of Panama.

Compare its length with greatest width of continent. Compare length of long slope (2,200 miles) with length of short slope (500 to 700 miles). Which slope has the longer coast-line? Mold in sand and chalk model, showing the two slopes and continental axis. Compare surface of both slopes. Which has the greater area of highlands? Which of plains? Give number and comparative size of lakes. Compare length and direction of rivers on each slope. What is the character of the coasts and harbors? What of the islands? Which slope has the larger inland drainage system? Compare with oceanic drainage system.

Locate highlands of each slope. Give the appearance of the Appalachian Mountain System. Compare with the Rocky Mountain System. What can be learned as to the general formation and altitude of each slope? (Show typical pictures.) What is the effect of altitude upon the surrounding country? What on drainage? What is the effect of large rivers upon plateaus?

Locate great central valley of North America. What two great rivers flow through this valley? Trace the Mississippi River from its source to its mouth. Trace the Mackenzie River in the same way. What separates the Mississippi basin from the Mackenzie basin? From the Saskatchawan basin? Trace lowest line from the mouth of the Mississippi to the mouth of the Mackenzie. Into what does this line divide the continent? (Into two land masses.)

Compare these two. In which is the continental axis? (In the primary land mass.) The secondary land mass is divided by the Appalachian Mountain System into two slopes, of which the eastern is called the Atlantic slope. Compare these slopes. Where do the Appalachian Mountains begin? (In the St. Lawrence basin.) Nearly to what gulf do they extend? (Gulf of Mexico.) What is their direction? What separates the secondary land mass into two parts—northern and southern? (The St. Lawrence River.) The northern part is the peninsula of Labrador. In this part trace the water partings of the Hudson Bay river system.

In the primary land mass two immense mountain ranges extend over 5,000 miles—nearly the entire length of the continent. What are these mountains called? Compare their general altitude with the low range of mountains (100 feet high) crossing the Isthmus of Panama. How wide is this Isthmus? (Fifty miles from coast to coast.)

What is known about a certain canal which has been begun in Panama? Is there any other important canal in Central America?

Commencing in the southern part of Mexico, and extending northerly and westerly, two great ranges bound the great plateau of Mexico on the east and west. This plateau is divided by the Rio Grande, Colorado, and other rivers, at a distance of about 500 miles north. The southern part of it is a volcanic region, in which are Popocatapetl and other high mountains.

What can be told about the Colorado River? (Show pictures of structure, also of ancient cliff dwellings.) What is the character of the rock through which the river cuts? Is it in the region of much rainfall or of no rainfall? North of the great plateau is the great basin, 600 miles wide and 900 miles from north to south, enclosed by the Sierra Nevada, Wasatch and Rocky Mountains.

What is the character of the large lake found here? Of what was it once a part? (Tell of old Lake Bonneville, and the terraces which record the height of its ancient waters, high up on the mountain sides, at the east of Salt Lake. Show pictures of structure of country and the effect of irrigation on the barren soil.)

What low range of mountains west of the Sierra Nevada range? Describe the beautiful valley lying between these ranges. Why is it fertile? What are its products? Describe the great red-wood trees.

What peninsula south of this is formed by the union of these two ranges? Locate Mt. Shasta, 14,442 feet high, in the Cascade range (a part of Sierra Nevada), just north of the California valley; also Mts. Tacoma, Hood, and Ranier, in the same range. Find Mt. St. Elias, in Alaska—the highest peak in North America, being 19,500 feet above sea level. (Show pictures of these mountains. Tell stories of Alaskan Indians.)

Yellowstone Park is in the Rocky Mountain range, east and north of Mt. Shasta. What do you know of this wonderful park? (Sketch geysers of Yellowstone Park.) Can the prevailing wind of the Pacific slope be confidently stated? What of the Atlantic slope? Compare the number and character of rivers, also the coastal planes of these two slopes.

What relation has the structure of a region to the amount of rainfall? Locate the region of greatest rainfall on the continent; also the region of no rainfall, or desert region. Compare with the rainfall of the home region. (Let the pupils chalk model the map again, showing the depressed axis, great plateau and mountain ranges: also indicating the character of coasts, whether high or low, and stating whether they are building or wearing coasts, and why.)

Name the river basins of each slope. Locate the basin of the Mississippi River, and trace its water partings. Give the general direction of the river and the reason for its flowing in this direction.

What great rivers are in the right slope of this basin? Which is the largest river? Why are the waters of the Missouri River colored? Which is the largest river in the left slope? Compare the two slopes. Which is the higher? Which has the greater number of river basins? Locate the Ozark Mountains. Are there any lakes in this basin? In which course of the river are the waterfalls or cascades found? (Show pictures of St. Anthony and Minnehaha Falls.)

What is the length of the Mississippi River in a direct line? (1,275 miles, while the length by water way is 3,160 miles.) What is to be inferred from these data as to the course of the river? What as to the slope of the land and the character of the soil? What must be the effect on navigation and commerce? In which course, upper, middle, or lower, are most of the windings? (Tell of the levees built to prevent the river from overflowing its banks.)

(The total length of the line of embankments, including those on both sides of the river and its tributaries, is 42,500 miles.)

At what rate is the river lowering the continent? (Enough sediment is annually carried down to cover twelve miles square of surface one foot deep.)

Where is the soil being deposited? How far is the river navigable? What canal is being dug to connect its waters with those of Lake Michigan? Consider the effect of this great work on the commerce of Chicago. What is the temperature in the northern part of the Mississippi River basin? What is the character of its vegetation? Compare these with those of the southern part. Where is the greatest rainfall? What besides fertile soil and abundant rainfall, is necessary to insure luxuriant vegetation? Name some fruits characteristic of the northern part of the basin, also of the southern part.

Locate areas of land best adapted to the growing of food plants; as grain, including rice; potatoes and sugar-cane; also those best for grazing purposes; the raising of cattle, sheep, etc. What plants produce materials for the manufacture of clothing? What areas are especially suitable to the growth of cotton? What to the growth of flax and hemp? Locate coal mines, and other mining districts; also lumber regions.

Where are the largest cities situated? Why are they thus located? What localities are best adapted to manufacturing purposes? Which to commerce? Interest the children in the discovery of the “great river.” Read accounts of Joliet’s and Marquette’s discoveries in 1673, also LaSalle’s discovery of its mouth in 1682.

Study the history of the early colonists and show the relation of their environment to their social and political development.

The further study of history will require a constant review of the geographical features of the continent, and will show their relation to the political divisions. These may be marked off upon the map with red chalk at the proper time.

In a similar manner each river basin of the continent may be studied separately, and the Hudson Bay basin. Compare the Atlantic and the Pacific, river basin systems, also Alabama and Texas systems of river basins.

Review the whole continent. See where the boundaries of all natural divisions coincide with the political divisions. Draw the continent, and mark all the large political divisions on the map. Add, also, the continental islands. How were these formed? What is a political division? What is its use? Mention the government of each division of the continent.

As the study of other continents are taken up, they may be compared with this one, and with each other, in regard to resemblances and differences.

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