Watch my number. -Each member of the New York Stock Exchange has a number. When it is
desired to call a broker from the floor of the exchange his number is made by means of an
electrical device to appear on an annunciator on the wall of the board room. If a broker has
occasion to leave the room he requests some fellow-broker to "watch my number" in order that he
may be apprised on his return if he has been called for.