Seth Thomas died from infection caused by an abcessed tooth at age 14.
Seth's death certificate says he was buried at Rice Cemetery. I believe his remains were moved to Dadeville Masonic, as his stone is there with other family members.
from Seth's obituary -- "He entered school at the early age of five under the guidance of his present teacher, and has climbed up through the grades without the loss of one. Though young and full of life, his conduct was such that not once did he have to be corrected. His daily life among his classmates was one of manly conduct and made himself one of the most respected and best liked of the student body."
As youngsters, Seth's cousin George Morris was one of his best friends.