View article

THE subject of this paper was first brought to the attention of one of the authors (RRC) in his capacity as parent of a fairly typical 10-year old boy. At the end of each term the headmaster of this child's school is in the habit of writing a circular letter to all parents reporting on matters of importance for the school and, incidentally, mentioning minor problems in the solution of which parents might be able to help. On a recent occasion the headmaster mentioned that the burgeoning popularity of digital watches which can be set to" bleep" on every hour was becoming something of a nuisance, particularly in the school morning assembly (which straddles 9 am). The presence in the school of a number of wearers of such watches was causing disturbance to the assembly. The problem is, of course, compounded by the near certainty that there will be a sufficient range of random errors in the time setting of any collection of …