 He did this not by succumbing to the imitation of country singing, but by investing whatever he sang with all the principles of good singing - of long and intelligent phrasing, clean, natural attack and diction, lively faithfulness to rhythm and timing, and the powerful engagement of imagination in interpretation.These values were explained in his 1912 book "Interpretation in Song" which ran through many editions and rapidly became a classic.His advocacy of art-song was indefatigable.