Voigtländer surveyor's level
Datecirca 1754
Inventory NumberDW0806
ClassificationSurveyor's Level
Subject
Maker
Johann Christoph Voigtländer
1732-1797
Cultural Region
Place of Origin
Dimensionslevel: 29.5 × 7.4 × 80.2 cm (11 5/8 × 2 15/16 × 31 9/16 in.)
base: 20.4 × 23.6 × 23.6 cm (8 1/16 × 9 5/16 × 9 5/16 in.)
assembled: 45 × 23 × 81 cm (17 11/16 × 9 1/16 × 31 7/8 in.)
base: 20.4 × 23.6 × 23.6 cm (8 1/16 × 9 5/16 × 9 5/16 in.)
assembled: 45 × 23 × 81 cm (17 11/16 × 9 1/16 × 31 7/8 in.)
Material
Accessorieswooden display stand
DescriptionBrass surveyor's level with the following major components: two spirit levels; telescope tube; level bar with single leveling screw; socket mount.
The larger of the two spirit levels is mounted parallel to the telescope tube, between the brass rings connecting the latter to the level bar. It has a single oval window marked at each end with two brass bands.
Mounted perpindicular to the telescope tube on the brass ring nearest the eyepiece is a smaller spirit level, with a single oval window having a brass bar at its center.
The otherwise plain brass telescope has a shaped eyepiece and objective end cap. Near the objective end of the tube is a single small circular knob. The telescope is suspended between two brass rings connected to the level bar, one by a threaded post, the other by direct contact.
The level bar is attached to a second horizontal bar by a hinge at one end. Projecting horizontally from the hinge is a circular knob. At the opposite end is a leveling screw, with a circular knob projecting down. The screw, which rests beneath the lower horizontal bar, is attached by a brass ring to a curved brass strip. The opposite end of the strip is bolted to the level bar, which may thus be tilted by turning the leveling screw.
Between the level bar and the socket mount is another, larger, circular knob, projecting horizontally from the vertical spindle. The cylindrical socket mount may be tightened or loosened by turning a key-shaped knob.
The level is mounted on a wooden display stand, painted black. The stand's circular base is chipped.
The larger of the two spirit levels is mounted parallel to the telescope tube, between the brass rings connecting the latter to the level bar. It has a single oval window marked at each end with two brass bands.
Mounted perpindicular to the telescope tube on the brass ring nearest the eyepiece is a smaller spirit level, with a single oval window having a brass bar at its center.
The otherwise plain brass telescope has a shaped eyepiece and objective end cap. Near the objective end of the tube is a single small circular knob. The telescope is suspended between two brass rings connected to the level bar, one by a threaded post, the other by direct contact.
The level bar is attached to a second horizontal bar by a hinge at one end. Projecting horizontally from the hinge is a circular knob. At the opposite end is a leveling screw, with a circular knob projecting down. The screw, which rests beneath the lower horizontal bar, is attached by a brass ring to a curved brass strip. The opposite end of the strip is bolted to the level bar, which may thus be tilted by turning the leveling screw.
Between the level bar and the socket mount is another, larger, circular knob, projecting horizontally from the vertical spindle. The cylindrical socket mount may be tightened or loosened by turning a key-shaped knob.
The level is mounted on a wooden display stand, painted black. The stand's circular base is chipped.
Signedengraved in script on lower horizontal bar: J. C. Voigtländer / in Wien
Curatorial RemarksImages B501038, B501039, B501040 may be removed. They are duplicated (in better exposure) in B501453, B501454, B501455.;
See the instrument file for a copy of the tag.
FunctionFor use in surveying, to measure contours.
After placing the Y level, on a tripod, at his starting location, the user levels the instrument by means of the spirit levels and the leveling screw. Then he sights a stadia rod through the telescope, moving the rod as needed until the target is centered behind the telescope's cross hairs. The difference in height between the telescope and the rod target indicates the gain in elevation over the horizontal distance between the two.
After placing the Y level, on a tripod, at his starting location, the user levels the instrument by means of the spirit levels and the leveling screw. Then he sights a stadia rod through the telescope, moving the rod as needed until the target is centered behind the telescope's cross hairs. The difference in height between the telescope and the rod target indicates the gain in elevation over the horizontal distance between the two.
ProvenanceDavid Wheatland purchased from Alain Brieux, Paris, April 25, 1964 (lot 15/7).
Etienne Lenoir
Date: circa 1830
Accessories: T-shaped mahogany case; knob for socket mount
Object number: 5214
Troughton & Simms
Date: circa 1830
Accessories: mahogany case with brass hooks and hinges, and felt protectors; additional eyepiece; magnifier; adjustable mirror; tripod mount; foot plate (5208b); tripod (5208b)
Object number: 5208a
Peter & John Dollond
Date: 1780-1800
Accessories: mahogany box with brass hooks, hinges, and handle; tripod (see 5240b)
Object number: 5240a
Frederick Eckel
Date: circa 1885
Accessories: mahogany case (top very worn); lens hood; sunshade; tripod, see 5151b
Object number: 5151a
Iszard-Warren Co., Inc.
Date: circa 1910
Accessories: mahogany case with brass corners and lock; key missing; leather strap; screwdriver; dust cover; sunshade; tripod, see 5150b
Object number: 5150a
C. L. Berger & Sons
Date: circa 1902
Accessories: pine case with lock (key not found); screwdriver; leather strap; sunshade; dust cover; tripod (see 5161b)
Object number: 5161a
Troughton & Simms
Date: circa 1840
Accessories: mahogany box with brass handle; sun shade for telescope
Object number: 5234
Jean Lefebvre (II)
Date: circa 1740
Accessories: wooden display stand
Object number: 5217
Buff & Berger
Date: circa 1880
Accessories: mahogany case; sunshade; screws; dust cover
Object number: 5143a