However, I think we shall be compelled to accept the change from the artistic to the scientific school of historians, though we may regret it as unavoidable. It is the vast enlargement of the field of historical study, the strong critical searchlight that is turned on all the dark corners and outlying tracts of this field, that is irresistibly affecting the work of writers, enforcing the need of caution, of scrutinising every point, of weighing evidence in the finest scales, of assaying its precise value. The contemporary writer has to deal with the huge accumulation of material to which I have already referred; he must ransack archives, hunt through records piled up, public and private, must decipher ancient manuscript, must follow the labours of the wandering collector of inscriptions and the excavator of old tombs. He has to make extracts from correspondence, diaries, and notes of travel which are coming for the first time to the light; he must keep abreast of foreign literature and criticism. The mass and multiplicity of documentary evidence now at his disposal, most of which may not have been available to his predecessors, is enormous. Some twelve years ago Lord Acton wrote: 'The honest student has to hew his way through multitudinous transactions, periodicals and official publications, where it is difficult to sweep the horizon or to keep abreast. The result has been that the classics of historical literature are found inadequate, are being re-written, and the student has to be warned that they have been superseded by later discoveries.'