Surveyor's Vernier Compass
"Wm. J. Young Maker Philadelphia"
length 14 inches; needle 5 inches
This compass is not dated, but we know that William J. Young began using this particular signature around 1840, and he began putting serial numbers on his instruments in the early 1850s. The variation arc on the north arm extends 27 degrees either way. The vernier is moved by rack and pinion located on the south arm and hidden under a brass plate, and reads to 5 minutes. There is a circular level vial on the south arm and an outkeeper on the north arm. The
face is dark, and the needle ring was probably originally silvered.