After a brief explanation of the method of simultaneous determination of time and latitude by the observation of several stars at equal altitudes, as practiced with the prismatic astrolabe of Claude and Driencourt, Danjon's new impersonal astrolabe is described and compared with the Meridian Circle.A brief discussion of the results obtained with astrolabe 0. P.L. is given. The possible contribution of this new instrument to fundamental position astronomy is considered.Asociación Argentina de Astronomía