  The properties of measuring systems of the Extensive Air Showers arrival
directions (EAS goniometers), consisting of the set of spatially separated
detectors registering the moments of EAS frontal passage, are considered. The
advantage of volumetric goniometers in comparison with the commonly used flat
ones is shown. The proper points selection method for detectors spatial
arranging is suggested, providing the best accessible estimation accuracy
within the given detectors number and installation overall dimensions
