Number

(num'būr.) [From L. numerus. ] (Arith.) An a emblage of several units or of several things of the same kind. Cardinal N. expre the amount, as 1, 2, 3, 4. Ordinal N. denote the order, as 1st, 2d, 3d, . Even N. are those which may be divided into two equal parts without a fraction being produced, as 6, 12, . Uneven N. are such as leave a remainder after being divided by 2, as 5, 13, . A rational N. is one commensurable with unity. A N. incommensurable with unity is termed irrational, or a surd. A square N. is the product of any N. multiplied by itself, as 4, which is the product of 2 multiplied by 2. A cubic N. is the product of a square N. by its root: such is 27, as being the product of the square N. 9 by its root 3. A perfect N. is that whose aliquot parts added together make the whole N., as 6, 28, .; the aliquot parts of 6 being 3, 2, and 1 = 6; and those of 28 being 14, 7, 4, 2= 28, . An imperfect N. is that whose aliquot parts added together make either more or le than the whole of it. Homogeneal N. are those referred to the same units, those referred to different units being termed heterogeneal.-(Gram.) The difference of terminal form in a word, to expre unity or plurality; thus, a word, the termination of which denotes one unit or individual, is in the singular N.; two or more, the plural N.(pl.) (Lit., dc.) Certain measures, or cadences, which render a verse, period, or song, agreeable to the ear. Poetical N. consist in a certain harmony in the order and quantity of syllables constituting feet. Rhetorical N. are a sort of simple harmony, le apparent than that of verse, but such as is perceived and affords pleasure to the mind. [s. 654]