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in questioning him on the meaning of each sentence, which he may be required to read, will be of incalculable advantage.

When pupils shall have been taught how to study, let them be required to get their lessons, and recite them. If the present book is not thought by teachers to contain a sufficient description, and a sufficient explanation of everything, let them try to find one that does, for if pupils present themselves before the blackboard at the time of recitation, with the expectation that the teacher is to explain to the class, and help them through with what they cannot go through themselves, they will not feel that they must have studied themselves; and the paltry oralizing of the teacher will not be listened to, or if heard, will not be understood, or at best, not retained in memory. Pupils may be made to see things for the moment, while no abiding impression will remain on their minds. They will often proceed, in such a manner, through a book, and perhaps have the mistaken idea that they understand its contents -to perpetuate the evil of superficialism, perhaps, themselves, as teachers. Pupils will never have a sufficient understanding of a subject till they shall have studied it carefully themselves, and mastered each part by severe personal application.

Recitation by analysis will be found more conducive to thorough scholarship than adherence to any written questions. Let the class, or any member of the class, be able to commence at the beginning and go through with the entire lesson without any suggestion from the teacher,

a thing that is perfectly practicable and easily attainable. Let pupils be called on, at the pleasure of the teacher, in any part of the class, to go on with the recitation, even to proceed with it in the midst of a subject, the topic in no case ever being named by the teacher. They will thereby become accustomed to give their attention to the recitation, and they will be profited from it, besides securing habits of attention, which will be of incalculable value.

In fine, let arithmetic be studied properly, and more valuable mental discipline will be acquired from it, than is often attained from the whole course in mathematics usually assigned by college faculties. It is not the extent, but the value of acquisitions in mathematics, which is desirable.

W. B. B.

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ARITHMETIC.

NOTATION AND NUMERATION.

¶ 1. A single thing, as a dollar, a horse, a man, &c., is called a unit, or one. One and one more are called two, two and one more are called three, and so on. Words expressing how many (as one, two, three, &c.) are called numbers.

This way of expressing numbers by words would be very slow and tedious in doing business. Hence two shorter methods have been devised. Of these, one is called the Roman* method, by letters; thus, I represents one; V, five; X, ten, &c., as shown in the note at the bottom of the page.

The other is called the Arabic method, by certain characters, called figures. This is that in general use.

* In the Roman method, by letters, I represents one; V, five; X, ten; L, fifty; C, one hundred; D, five hundred; and M, one thousand.

As often as any letter is repeated, so many times its value is repeated, unless it be a letter representing a less number placed before one representing a greater; then the less number is taken from the greater; thus, IV represents four; IX, nine, &c., as will be seen in the following

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every additional Ɔ an

*I is used instead of D to represent five hundred, and for

nexed at the right hand, the number is increased ten times.

†CIO is used to represent one thousand, and for every C and put at each end, the

number is increased ten times.

! A line over any number increases its value one thousand times.

In the Arabic method the first nine numbers have each a separate character to represent it; thus,

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Nine is the largest number which can be expressed by a single figure. There is another character, 0; it is called a cipher, naught, or nothing, because it denotes the absence of a thing. Still it is of frequent use in expressing numbers.

By these ten characters, variously combined, any number may be expressed.

The unit 1 is but a single one, and in this sense it is called a unit of the first order. All numbers expressed by one figure are units of the first order.

3. Ten has no appropriate character to represent it, but it is considered as forming a unit of a second or higher order, consisting of tens. It is represented by the same unit figure 1 as is a single thing, but it is written at the left hand of a cipher; thus, 10, ten. The 0 fills the first place, at the right hand, which is the place of units, and the 1 the second place from the right hand, which is the place of tens. Being put in a new place, it has a new value, which is ten times its simple value, and this is what is called a local value.

Questions.¶ 1. What is a single thing called? What is a number? Give some examples. How many ways of expressing numbers shorter than writing them out in words? What are they called? Which is the method in general use? In the Arabic method, how many numbers have each a separate character?

2. How is one represented? Make the characters to nine. What are these nine characters called? Why? What is the simple value of figures? What is the largest number which can be represented by a single figure? What other character is frequently used? Why is it called naught? How many are the Arabic characters? What are numbers expressing single things called?

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