It is consistent with any possible value of the continuum c that every infinite-dimensional Banach space of density <= c condenses onto the Hilbert cube.Let mu < c be a cardinal of uncountable cofinality. It is consistent that the continuum be arbitrary large, no Banach space X of density gamma, mu < gamma < c, condenses onto a compact metric space, but any Banach space of density mu admits a condensation onto a compact metric space. In particular, for mu = omega 1, it is consistent that c is arbitrarily large, no Banach space of density gamma, omega 1 < gamma < c, condenses onto a compact metric space. These results imply a complete answer to the Problem 1 in the Scottish Book for Banach spaces: When does a Banach space X admit a bijective continuous mapping onto a compact metric space?