Observations of the Southern Reference Star (SRS) and Bright Star (BS) programmes were started in January 1963 with the Repsold meridian circle of the Santiago Observatory. Up to July 1, 1967, a total of 86725 star observations arranged in 1520 series had been observed.
In order to investigate the instrumental system, series of fundamental stars between +41° and −69° SP were included in the observing programme. A total of 214 such series were observed, 123 being with ‘clamp East’ and 91 with ‘clamp West’. The number of individual star observations in these 214 series was 7344. These observations were reduced using Bessel’s formula
α = T + (u + m) + n tan δ + c′ sec δ,
where u denotes the clock correction and c′ includes the collimation error, diurnal aberration and the contact width.