This device at Smith’s Tavern is a mole trap. It is a metal spring-loading three-spear trap. The trap was set in the path that a suspected mole digs in the yard. The spring is set by twisting the handle and locked into place with the side lever. The two outer prongs hold the trap steady in the ground. The three-speared prongs will fire when a mole touches the device.
While this device at Smith’s Tavern seems to be a primitive form of pest control, the exact same device is still sold today.