SIGNALING by flags, commonly called semaphore signaling, is great fun to practice with your friends outdoors. This type of signaling is necessarily limited, since both the sender and the receiver must be within visual distance of each other, but it is none the less exciting.

The semaphore hand flags are easy to make, usually about 18 inches square, divided diagonally in two colors-red and white-and mounted on a 24-inch staff.

Taking the alphabet in order, you will find that for the most part the letters are made in clockwise succession, with one of the flags maintaining a constant position for a number of letters. Thus the easiest way to learn the alphabet is to learn at one time all the letters made with one of the flags in the same position. For example: The letters from A to D inclusive are made clockwise, starting with the right-hand flag in the position shown here. The left flag remains at the bottom or "interval" position for each of these letters through D, while the right flag moves upward for each successive letter. For the letters E, F and G, the right flag assumes the interval position, while the left flag continues the clockwise movements.

There are lots of words you can spell with these few letters, so before progressing any farther, practice sending and receiving words made up from them.

The second part of the alphabet, made up of the letters H to N inclusive (except J), are also made in clock-like order. In the cast of these letters, the starting point of the right flag is a straight point from the shoulder-the "nine o'clock position"-while the left flag remains in the lower right position to make H and I. The letters K, L, M and N are made with the right flag in the lower right position, and the left flag continuing the clock movements.

The next group-P, Q, R and S-the right flag remains stationary in the "nine o'clock position," while the left flag moves clockwise. To make J, V and D, the right flag remains directly above the head, and the left flag varies according to the letter being made. K, P and T are similar, except that the left flag is directly above the head.

The letters U, R and N are made with both arms in the same position on opposite sides of the body.

The letters U, R and N