The traditional approach to the extragalactic distance scale rests on a pyramid of primary, secondary and tertiary indicators of increasing range and decreasing accuracy. This multi-step procedure, fraught with the danger of cumulative errors, has led in recent years to two main, widely diverging scales: the 'long' scale (Sandage and Tammann 1974, 1975, 1976) implying a Hubble constant and the 'short' scale (de Vaucouleurs 1978, 1979; de Vaucouleurs and Bollinger 1979; de Vaucouleurs and Peters

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... 1981; de Vaucouleurs et al. 1981) leading to H 0 ≃ 100. Several authors have already shown that the long scale rests on very precarious foundations (Capaccioli and Fasano 1980, de Vaucouleurs 1981, Hanes 1980); counter arguments have been offered in its defence and to criticize the short scale (Tammann, Sandage and Yahil 1979, Sandage and Tammann 1982). For want of a conclusive test a consensus was still lacking.