Thomas M. Preble (1810-1907)
T. M. Preble was a Freewill Baptist minister of New Hampshire, and Millerite preacher. He accepted the Sabbath in the middle of 1844 (perhaps from Mrs. Rachel Oakes or someone else in Washington, New Hampshire). He was the first Adventist to advocate the Sabbath in print. His article in the Hope of Israel (an Adventist periodical of Portland, Maine) of February 28, 1845, was reprinted in tract form in March under the title Tract, Showing That the Seventh Day Should Be Observed As the Sabbath. This introduced the seventh-day Sabbath to Joseph Bates, who later wrote his own tract on the Sabbath. But Preble observed the seventh day only until the middle of 1847. In later years he wrote against the Sabbath in the World’s Crisis (an Advent Christian paper) and in his book First-Day Sabbath.
(Source: SDA Encyclopedia)