74070881
Jun 19, 1990
May 14, 1991
gravity meters, magnetometers, induced polarization equipment, gamma radiation and radon measuring instruments, electromagnetic detection apparatus and portable seismic receivers, all for use in the exploration for natural resources including minerals, petroleum, and ground water, and for civil engineering purposes; detectors for vapours arising from explosives and detectors of trace amounts of narcotics, monitors for nitrogen oxides, sulphur vapours, ozone and other atmospheric pollutants; monitoring devices for tritium, beta and gamma rays
Electrical and Scientific Apparatus