During the late 19th century , the UKHO took part in several international conferences , including the International Meridian Conference to determine a prime meridian for international use and other conferences working towards the establishment of a permanent international commission concerning hydrographic matters . Hydrographers to the Admiralty Board during this period included : Rear-Admiral John Washington , Rear-Admiral George Henry Richards , Captain Sir Frederick J O Evans and Rear-Admiral Sir William J L Wharton
International Meridian Conference
International Meridian Conference
United Kingdom Hydrographic Office