The Gilbert 21 software is able to select records based on geographic areas.
To use this feature the geographic area has to be specified as a 'polygon'
(area) in a boundary file. These are just text files with a pair of OS easting
and northings (separated by a space) on each line. Each line represents a point
on the boundary of the polygon. A number of these files that could be
particularly useful for selecting records for export have been prepared for you.
You can download these here.
To use any of the files which you can download here, follow this procedure:
- Download the required boundary zip file to convenient location on your computer
- Unzip it
- Select the 'Open records by polygon' item of the 'File' menu in Gilbert 21
- Locate the unzipped boundary file - all the records in your database which are
within the are described by the polygon are selected