The Second Cambridge Catalogue of Radio Sources (2C) was published in 1955 by John R Shakeshaft and colleagues.
The observations were made with the Cambridge Interferometer, at 81.5 MHz.
The data appeared to show a flux/number ('source counts') trend which precluded some cosmological models (such as the Steady-State):- For a uniform distribution of radio sources the slope of the cumulative distribution of log(number, N) versus log (power, S) would have been -1.5, but the Cambridge data apparently implied a (log(N),log(S)) slope of nearly -3.0.
Key data demonstrating this came from the then-recently commissioned Mills Cross Telescope in Australia.
However, subsequent statistical analysis by Hewish of the interferometer records later showed some aspects of the initial interpretation to have been broadly correct, with the correct measure of the (log(N),log(S)) slope of nearly -1.8 derived once confusion was taken into account.