Madam, - While I heartily agree with Claire Murphy's criticism of inappropriately low speed restrictions (March 30th), I fear she misunderstands the distinction between the two sizes of circular speed-limit signs. The larger sign indicates the start of a speed limit zone - 50kph or whatever. The smaller signs acting as reminders of the continuance of the speed limit. - Yours, etc.,
E. V. MORRISSEY, Dublin 14.