In an earlier contribution to this Review [1] in July 1976 the UK Hydrographic Department’s experiences with digitising equipment were described. The procedures by which data were digitised on offline tables and then edited on a Ferranti interactive editing station were discussed. A later paper by Tolson [2] indicated, amongst other things, the use the UK Hydrographic Department were making of voice recognition equipment to help with the encoding of graphical sounding data on an offline digitiser table. Details of the computer-assisted techniques being used at sea in some of the UK hydrographic surveying fleet have also appeared in an earlier issue of this Review [3] and elsewhere [4]. It is the intention of this paper to report the recent progress made by the UK Hydrographic Department in the area of computer assisted cartography
