Work and Play in Girls' Schools / By Three Head Mistresses

by Dorothea Beale; J. F. Dove; Lucy Helen Muriel Soulsby

In this lesson may also be introduced a few words about the temperature of the given country so far as it is dependent on latitude.

Lesson III. Height above sea level.

Contouring.For this lesson the teacher should have drawn and painted for the class a map of the continent being studied, with contour lines marked in two different colours or with two different kinds of lines. (Too great detail only tends to confuse the children.)

The first contour line should be drawn joining all places 500 feet above the sea level, and the second joining all those places 1500 feet above sea level. Each child should then be provided with one of these maps, and a wall map similarly contoured and also coloured should be hung on the wall.

The teacher then explains the nature of contour lines, and shows that if that part of the map between the 500 contour line and the sea be coloured green, the coloured part will represent all that part of the land which is less than 500 feet high, that is, generally speaking, the plains. That part between the 500 and 1500 contour lines is then coloured light brown, and all those areas enclosed within the 1500 contour line a darker brown. When the maps are coloured, and each child has her own, they may then be taught how to read a map so coloured. The teacher will draw from the class that if the contour lines come close together the ground slopes very rapidly, but that the slope is more gradual when the contour lines are more widely separated—that the greatest height of the land lies near the greater ocean, and that the more gradual slope is towards the smaller ocean, and that this allows of the development of larger but slower rivers than those flowing down the steeper slope.

A raised model may then be shown to the class, and this may be coloured in the same way as the maps, but the children must clearly understand the disadvantages of a model, and be shown that the vertical heights are always enormously exaggerated in proportion to the horizontal distances.

In recapitulating, the children might be asked what they consider a common slope for the sides of mountains. Their notions will always be found to be extravagant, many of them thinking they have seen and even climbed slopes of 60 degrees and upwards. By placing a piece of india-rubber on the cover of a book, and gradually opening the book and sloping the cover till the india-rubber rolls off, the children may be shown how very small is the angle at which it is perfectly impossible for anything to rest on a slope, and that therefore if we find stones on the side of a hill, we know that the slope cannot be greater than 30 degrees. Examples may be drawn from any hill in the neighbourhood of the school.

Lesson IV. A second lesson will be necessary on the contour of the given continent, when the names of the mountain ranges and of the plains may be given, short descriptions of them read, and exercise given in filling them into a blank map from memory.

Position of rivers.Lesson V. The teacher fills into a wall map, blank and uncontoured, the principal rivers, and asks the class to put them in their contoured maps. Many of the children will be found not to have appreciated the meaning of contour lines, but will have drawn a river flowing from the part coloured green to that part coloured brown. One such map will form a good object-lesson, and the children can be brought to see the absurdity of what they have done in representing a river as flowing up a hill.

The properly contoured wall map may then be hung up, and the actual position of the rivers followed. The meaning of watershed will now be apparent, and the fact should be noted that it does not necessarily or even generally correspond with the highest land.