LESSON XXXI.

In this lesson let the pupil be first taught that a single thing is represented by 1; that 1 and a naught at the right represent a unit of the second order; 1 and two O's, a unit of the third order; 1 and three 0's, a unit of the fourth order; 1 and four O's, a unit of the fifth order; and so on for any number of places, according to the following table.

Let the pupil be now taught the relative value of these units; viz., that ten units of the first order make one of the second; ten of the second one of the third; ten of the third one of the fourth; and so on for all the values. Let the teacher put the questions: What is a unit? Ans. It is a single thing. What is a unit of the second order? Ans. A single ten.-What is a unit of the third order?