Question: Who was the teacher of T. M. Preble?

Context paragraphs:
T. M. Preble: Thomas Motherwell Preble (1810–1907) was a Free Will Baptist minister in New Hampshire and a Millerite preacher.  After accepting the teachings of William Miller, Preble was excommunicated from his church.

William Miller (preacher): William Miller (February 15, 1782 – December 20, 1849), an American Baptist preacher, is credited with beginning the mid-19th century North American religious movement known as the Millerites.  After his prophecies of the Second Coming did not occur as expected in the 1840s, new heirs of his message emerged, including the Advent Christians (1860) and the Seventh-day Adventists (1863).  Later movements found inspiration in Miller's emphasis on Bible prophecy; the Bahá'í Faith holds that his predictions of 1844 events were accurate.

Supporting paragraphs: T. M. Preble William Miller (preacher)
Answer: William Miller