The automatic measuring machine acquired by the U.S. Naval Observatory in 1966 was built by Nuclear Research Instruments (NRI) in Berkeley, California, based upon design specifications by the Naval Observatory and upon a considerable amount of innovative engineering by NRI. The performance of the machine and the results obtained over the past four years clearly show that a reliable high speed measuring system has been achieved. Hence, when requirements developed for a second machine it was decided to copy the earlier machine, incorporating modifications which the present state of the art permit and which were not available when the machine was designed in 1963.