A classical style table clock by Nathan Adams of Boston, MA. Made between 1796 and 1810. Though he started his career as a cabinetmaker in the early 1780s, he switched to clockmaking by 1786. He was listed in the Boston directories as both a clockmaker and cabinetmaker, so it is possible that he made both the case and the clock. The applied carved classical décor was likely made by a carving specialist in Boston.
We currently have two shelf clocks like this, but both were made in England. American made shelf clocks like this, especially with the applied carved décor are very rare in American cabinetmaking.