In September 1946 workers directed by the Jewish Historical Commission in Poland recovered ten metal boxes buried in the basement of what had been a Jewish school in the Warsaw Ghetto, but which was then a precarious heap of rubble. The boxes contained the first collection of documents and records assembled by the Oyneg Shabes group in the ghetto and buried for safe-keeping. This remarkable enterprise had operated for four years under the cover of a Jewish self-help organisation run by Emanuel Ringelblum, a Jewish historian of pre-war eminence who had perished during the war. In December 1950, a second cache was unearthed. These papers were contained in two milk churns and were in better condition than the first lot, which had suffered extensive damage. A third batch of material was never found, despite efforts made by the only three survivors of the group.