Mantel clocks, otherwise known as shelf clocks, began replacing long-case (grandfather) clocks when spring-driven movements became available. Previously, clock cases were necessarily tall and bulky because weight-driven movements required a relatively long drop in order to operate. Mantel clocks also became more popular and affordable when mass-production methods were introduced.
Unmarked metal front mantel clock, brass case w/angel figure at top, 30-hour, time only, patented Oct. 18,1902, 8 x 10″ h. $95.