Henry Livingston, Jr. lived during an extraordinary period of history. He served as a Major in the Revolutionary War, and watched the creation of a new country, led by his brothers and cousins and uncles. But while Henry stayed at home tending to his farm and surveying work, he was also writing poetry for his family and friends. Among his poems was one of the most famous American poems that is still recited today: "The Night Before Christmas".After Henry's original manuscript was burnt in a house fire, and Clement Moore took credit for Henry's poem, his descendants had difficulty proving Henry to be the actual poet. It took Auckland University Emeritus Professor MacDonald Jackson two solid years of research examining such unconscious linguistic characteristics as the way the tongue moves in the mouth to develop a set of tests that could distinguish the poetry of Henry Livingston from that of Clement Moore. When those tests were applied to the celebrated Christmas poem, it showed that "The Night Before Christmas" shared those instinctive habits of speech with Henry Livingston, and not with Moore. Finally, after almost 200 years, the beliefs of Henry's descendants have been vindicated. Henry Livingston, Jr. has been shown to be the true author of "The Night Before Christmas."Mary Van Deusen is Henry Livingston's fifth great granddaughter. A computer scientist, Mary acted as research assistant to Vassar Professor Don Foster and MacDonald Jackson in their author attribution research.