stadia rod target
Date: circa 1910
Inventory Number: 2003-1-0241a
Classification: Surveyor's Level
Subject:
Maker: American ?
Cultural Region:
Dimensions:
10.5 x 13.5 x 10.5 cm (4 1/8 x 5 5/16 x 4 1/8 in.)
blue board box: 13.3 × 31.8 × 16.7 cm (5 1/4 × 12 1/2 × 6 9/16 in.)
Description:
Circular iron plate bent into a ninety-degree angle down the middle, with a rectangular cutout near the center of one face. The four quardrants of the faces of the plate are alternately painted white and red. Bolted to one face of the plate against the edge of the cutout is a sloped brass piece printed with a scale with values ranging from 0 to 10.
Two iron brackets bolted to the back of the plate on either side of the cutout may be used to attach the target to a stadia rod. Four iron rollers, two smooth and sticking out beyond the edges of the plate, and two knurled and within the edges of the plate, aid the stadia rod in sliding up and down the brackets. A brass screw having a circular knurled knob extending past the edge of the plate may be tightened against the stadia rod.
Two iron brackets bolted to the back of the plate on either side of the cutout may be used to attach the target to a stadia rod. Four iron rollers, two smooth and sticking out beyond the edges of the plate, and two knurled and within the edges of the plate, aid the stadia rod in sliding up and down the brackets. A brass screw having a circular knurled knob extending past the edge of the plate may be tightened against the stadia rod.
Signedunsigned
FunctionFor use in surveying. Attached to a stadia rod and held in place by one surveyor, the stadia rod target is viewed by a second surveyor through a level or similar instrument. The first surveyor then moves the rod and target according to the second surveyor's instructions, with the rod's final location being the point from which the horizontal distance (or other desired quantity) from the viewing instrument may be measured.
ProvenancePrivate Donor, Troy, NY, 2003.