APPLICATION OF THE EDUCATION OF THE VISUAL SENSE TO THE OBSERVATION OF THE ENVIRONMENT
_Nomenclature._ This is one of the most important phases of education. Indeed, nomenclature prepares for an _exactness_ in the use of language which is not always met with in our schools. Many children, for example, use interchangeably the words thick and big, long and high. With the methods already described, the teacher may easily establish, by means of the didactic material, ideas which are very exact and clear, and may associate the proper word with these ideas.
_Dimensions._ The directress, after the child has played for a long time with the three sets of solid insets and has acquired a security in the performance of the exercise, takes out all the cylinders of equal height and places them in a horizontal position on the table, one beside the other. Then she selects the two extremes, saying, "This is the _thickest_--This is the _thinnest_." She places them side by side so that the comparison may be more marked, and then taking them by the little button, she compares the bases, calling attention to the great difference. She then places them again beside each other in a vertical position in order to show that they are equal in height, and repeats several times, "thick--thin." Having done this, she should follow it with the test, asking, "Give me the thickest--Give me the thinnest," and finally she should proceed to the test of nomenclature, asking, "What is this?" In the lessons which follow this, the directress may take away the two extreme pieces and may repeat the lesson with the two pieces remaining at the extremities, and so on until she has used all the pieces. She may then take these up at random, saying, "Give me one a little thicker than this one," or "Give me one a little thinner than this one." With the second set of solid insets she proceeds in the same way. Here she stands the pieces upright, as each one has a base sufficiently broad to maintain it in this position, saying, "This is the highest" and "This is the lowest." Then placing the two extreme pieces side by side she may take them out of the line and compare the bases, showing that they are equal. From the extremes she may proceed as before, selecting each time the two remaining pieces most strongly contrasted.