High resolution observations of the quasar 3C 138.

The results of VLBI observations of the quasar 3C138 at 1667 MHz are presented. The source is about 0.45 arcsec long and has one widely separated component that departs considerably from the overall source linearity. The structure indicates a core/one-sided-jet morphology and concurs with the structure found ten years ago at 2631 MHz. Topics covered include superluminal motions, magnetic field strength, and polarization. The energy loss rate is given as approximately 10 to the 46th erg/s. No evidence for an extended radio component was found, and consequently, it is suggested that the observed jet is inefficient in transferring the energy it carries to large distances and dissipates all of it by bulk kinetic energy losses, or in the first few kpc before dying.