Note 5 — ELECTRICITY, WHAT ITS MASTERY MEANS: WITH A REVIEW AND A PROSPECT

Permutations are the various ways in which two or more different things may be arranged in a row, all the things appearing in each row. Permutations are readily illustrated with squares or cubes of different colours, with numbers, or letters.

Permutations of two elements, 1 and 2, are (1 x 2) two; 1, 2; 2, 1; or a, b; b, a. Of three elements the permutations are (1 x 2 x 3) six; 1, 2, 3; 1, 3, 2; 2, 1, 3; 2, 3, 1; 3, 1, 2; 3, 2, 1; or a, b, c; a, c, b; b, a, c; b, c, a; c, a, b; c, b, a. Of four elements the permutations are (1 x 2 x 3 x 4) twenty-four; of five elements, one hundred and twenty, and so on. A new element or permutator multiplies by an increasing figure all the permutations it finds.