(19)

(11)

EP 0 513 061 A1

(12)

(43) Date of publication: 19.11.1992 Bulletin 1992/47 (21) Application number: 91902725.0 (22) Date of filing: 18.01.1991

(51) International Patent Classification (IPC):  G01C 3/ 00( . ) (86) International application number: PCT/GB1991/000076 (87) International publication number: WO 1991/010878 (25.07.1991 Gazette 1991/17)

(84) Designated Contracting States: AT BE DE DK FR IT NL SE (30) Priority: 18.01.1990 GB 19900001154 (71) Applicant: WESTMORELAND, Michael Balderton, Newark, Nottinghamshire NG24 3HJ (GB)	(72) Inventor: WESTMORELAND, Michael Balderton, Newark, Nottinghamshire NG24 3HJ (GB) (74) Representative: Craske, Stephen Allan, et al  Craske & Co. Patent Law Chambers 15 Queens Terrace Exeter South Devon EX4 4HJ Exeter South Devon EX4 4HJ (GB)