194 THE MONTESSORI METHOD
enamel. The largest cube has a base of 10 centimetres, the smallest, of 1 centimetre, the intervening ones decrease 1 centimetre each. A little green cloth carpet goes with these blocks. This may be of oilcloth or cardboard. The game consists of building the cubes up, one upon another, in the order of their dimensions, constructing a little tower of which the largest cube forms the base and the smallest the apex. The carpet is placed on the floor, and the cubes are scattered upon it. As the tower is built upon the carpet, the child goes through the exercise of kneeling, rising, etc. The control is given by the irregularity of the tower as it decreases toward the apex. A cube misplaced reveals itself, because it breaks the line. The most common error made by the children in playing with these blocks at first, is that of placing the second cube as the base and placing the first cube upon it, thus confusing the two largest blocks. I have noted that the same error was made by deficient children in the repeated trials I made with the tests of De Sanctis. At the question, " Which is the largest ? " the child would take, not the largest, but that nearest it in size.
Any of these three sets of blocks may be used by the children in a slightly different game. The pieces may be mixed upon a carpet or table, and then put in order upon another table at some distance. As he carries each piece, the child must walk without letting his attention wander, since he must remember the dimensions of the piece for which he is to look among the mixed blocks.
The games played in this way are excellent for children of four or five years; while the simple work of arranging the pieces in order upon the same carpet where they have been mixed is more adapted to the little ones between three and four years of age. The construction of the tower