Inclusive jet production at √s=1.8 TeV has been measured in the CDF detector at the Fermilab Tevatron ¯pp Collider. Jets with transverse energies (Et) up to 250 GeV have been observed. The Et dependence of the inclusive jet cross section is consistent with leading-order quantum-chromodynamic calculations, and comparison with lower-energy data shows deviations from scaling consistent with QCD. A lower limit of 700 GeV (95% confidence level) is placed on the quark compositeness scale parameter Λc associated with an effective contact interaction.Received 3 November 1988DOI:https://doi.org/10.1103/PhysRevLett.62.613©1989 American Physical Society