[en] A NA-4 cylindrical-symmetrical focusing spectrometer operating since 1979 in a muon beam at the CERN 400 geV accelerator is described. The device is intended for the investigation of deep inelastic muons interactions with nucleons and nuclei at 120, 200, 240 and 280 GeV to study their structure at small distances to 10^-5 cm. Results of analysis of experimental data obtained using carbon targets are given. Conclusions obtained earlier for lower energies, that the nucleon composition includes fractional charge particles-quarks or partons, were confirmed. The Λ parameter necessary for the quark interaction description within the framework of quantum chomodynamics was determined, the lower boundary of the product of upsilon particles by the probability of decay into two muons was established. The NA-4 carbon targets were replaced by liquid hydrogen (deuterium)