Sir Thomas Walker Arnold (1864, Devonport, Devon – 1930) was an eminent British orientalist and historian of Islamic art who taught at MAO College, Aligarh Muslim University, then Aligarh College, and Government College University, Lahore. He was a friend of Sir Syed Ahmed Khan, and wrote his famous book "The preaching of Islam" at the insistence of Sir Syed. He was also the teacher of famous poet-philosopher Muhammad Iqbal, Syed Sulaiman Nadvi and a very close friend of Shibli Nomani who was also a teacher at Aligarh.
I read it during my Graduate Sociology classes. It gave me some great insights to prepare my course project papers, "The Impact of Religion on Islamic Arts" and "Depiction of Prophets in Visual Art".