  Our study exploits the Constant Intensity Cut principles applied
simultaneously to muonic and electromagnetic detectors of cosmic rays. We use
the fact that the ordering of events according to their signal sizes induced in
different types of surface detectors provides information about the mass
composition of primary cosmic-ray beam, with low sensitivity to details of
hadronic interactions. Composition analysis at knee energies is performed using
Monte Carlo simulations for extensive air showers having maxima located far
away from a hypothetical observatory. Another type of a hypothetical
observatory is adopted to examine composition of ultra-high energy primaries
which initiate vertical air showers with maxima observed near surface
detectors.
