'Abdu'l-Bahá's journey across America was remarkable. He was 68 years old and had been a prisoner most of His life. When He set out from Egypt He was unwell and planned only to travel to the American East coast and to Chicago. However, the American Bahá'ís begged Him to visit their communities and He undertook the strenuous three thousand-mile journey across the continent by train, sitting up most nights in a chair rather than spend money on a sleeping compartment. He spoke at public meetings nearly every day, sometimes three times a day, and gave hundreds of private interviews. His hectic and exhausting schedule is well-documented by Mírzá Mahmúd, who frequently alludes to the anxiety of the Master's companions over His health. Mahmúd's telling references to the simplicity of 'Abdu'l-Bahá's lifestyle -- `For dinner, 'Abdu'l-Bahá ate only a little bread and cheese and went to bed' -- contrast with the opulent lives lived by many of the Americans who visited Him.
(Preface to 'Mahmud’s Diary', published by George Ronald, 1997)