surveyor's Y-level
Date1905-1907
Inventory Number5162a
ClassificationSurveyor's Level
Subject
Maker
Bausch, Lomb, Saegmuller Company
1905 - 1907
User
Department of Engineering Sciences, Harvard University
founded circa 1918
Cultural Region
Place of Origin
Dimensionslevel: 21.3 × 11.5 × 52.3 cm (8 3/8 × 4 1/2 × 20 9/16 in.)
case: 26.2 × 57.4 × 17.2 cm (10 5/16 × 22 5/8 × 6 3/4 in.)
case: 26.2 × 57.4 × 17.2 cm (10 5/16 × 22 5/8 × 6 3/4 in.)
Material
Accessoriesscrewdriver; key; dust cap; sunshade; carrying case; tripod (5162b)
DescriptionThis elegant surveyor's level has a reversable telescope mounted in wye supports.
The telescope is made of brass with a dark green, crackle finish on the tube and other fittings made of bright brass or brass tinted by lacquer. The dust cover is of blackened aluminum. The brass bracket to hold the focusing knob on top of the tube assembly is also black. The telescope has two nested tubes which extend by turning brass ferrules with crisscrossed knurling. The pancratic eyepiece has variable power, and it is adjusted by turning the milled head on the smaller ferrule, which has a silvered scale divided into 18 parts marked 24, 30, and 36. These refer to "diameters." It is marked as "Patented Sept. 1, '03." Turning the milled ferrule on the larger tube adjusts focus on the cross hairs. There are opposing screws for tightening the cross hairs.
The tube is reinforced with brass bands where it sits in the wye brackets. The brackets are damascened, with hinged tops and bottoms. Pins tied to the pillars of the brackets are used to secure the hinged top to the bottom after the telescope tube is placed.
There is a hanging bubble level suspended below the telescope tube. It is of brass enameled in black and has a graduated glass.
The supports for the telescope are fixed to a horizontal diamond shaped platform (also enameled in black), which rotates on the central axis of the tripod mount. There is a bright brass locking screw to limit the quick rotation and a slow motion tanget screw.
The mount has a four-armed casting with a black crackle finish. Each arm sits on a leveling screw mounted to a parallel plate of blackened brass. The plate has a knurled rim. The underside of the plate has a large threaded socket to be mated with a fitting on top of the tripod.
With fitted mahogany case padded in green felt. Accessories include a walnut- handled screw driver, a double wrench, a sunshade with a textured black antireflective coating on the interior, a cloth bag tied up with string and holding some screws, part of a leather strap, and a case key. Instructions for using the variable power eyepiece are stuck to the inside lid of the box.
The telescope is made of brass with a dark green, crackle finish on the tube and other fittings made of bright brass or brass tinted by lacquer. The dust cover is of blackened aluminum. The brass bracket to hold the focusing knob on top of the tube assembly is also black. The telescope has two nested tubes which extend by turning brass ferrules with crisscrossed knurling. The pancratic eyepiece has variable power, and it is adjusted by turning the milled head on the smaller ferrule, which has a silvered scale divided into 18 parts marked 24, 30, and 36. These refer to "diameters." It is marked as "Patented Sept. 1, '03." Turning the milled ferrule on the larger tube adjusts focus on the cross hairs. There are opposing screws for tightening the cross hairs.
The tube is reinforced with brass bands where it sits in the wye brackets. The brackets are damascened, with hinged tops and bottoms. Pins tied to the pillars of the brackets are used to secure the hinged top to the bottom after the telescope tube is placed.
There is a hanging bubble level suspended below the telescope tube. It is of brass enameled in black and has a graduated glass.
The supports for the telescope are fixed to a horizontal diamond shaped platform (also enameled in black), which rotates on the central axis of the tripod mount. There is a bright brass locking screw to limit the quick rotation and a slow motion tanget screw.
The mount has a four-armed casting with a black crackle finish. Each arm sits on a leveling screw mounted to a parallel plate of blackened brass. The plate has a knurled rim. The underside of the plate has a large threaded socket to be mated with a fitting on top of the tripod.
With fitted mahogany case padded in green felt. Accessories include a walnut- handled screw driver, a double wrench, a sunshade with a textured black antireflective coating on the interior, a cloth bag tied up with string and holding some screws, part of a leather strap, and a case key. Instructions for using the variable power eyepiece are stuck to the inside lid of the box.
Signedon side of supporting frame: BAUSCH, LOMB, SAEGMULLER CO., Rochester N. Y.
Inscribedscale on telescope tube: Patented Sept. 1, '03.
serial number on supporting frame: 4445
on label pasted into lid of box: Directions for Using the Variable Power Eyepiece [followed by a text and diagram]
FunctionIn such an instrument, the telescope can be lifted and reversed, end for end. The telescope is for sighting distant objects, while the bubble level is to make sure the telescope is horizontal. This instrument permits direct measurement of differences in elevation.
ProvenanceFrom the Department of Engineering, Harvard University; purchased by David P. Wheatland in 1961.
Andrew Yeates
Date: circa 1840
Accessories: case, second eyepiece, plumb bob
Object number: 5235
Buff & Buff Manufacturing Company
Date: circa 1905
Accessories: wood case; leather case; right-angle prism; plumb bob; oil flask; tripod (5174b)
Object number: 5174a
American
Date: circa 1790
Accessories: Large brass key for tightening joints
Object number: 5006
Adie & Son
Date: circa 1850
Accessories: case; dust cap and sunshade; eyepiece
Object number: 5209
Wm Gaertner & Company
Date: 1900-1920
Accessories: micrometer eyepiece, eyepiece adaptor
Object number: 1997-1-1836
Legey
Date: circa 1838
Accessories: shades with double tabs (4); shades with single tab (4); screwdriver and square key.
Object number: 5268
Ernst Leitz (company)
Date: circa 1937
Accessories: standard eyepieces (3): 8X P, Periplan. OK 10X, and Periplan. Ok. 25X; wide eyepieces (3): 1, 1, 8X, 10X; objectives (4) in fitted case: 1b 4.3X, 3 10X, P7 62X, P 1/12 oel; waveplates (2); condenser with polarizer; mechanical stage; loupe 6x; box of cover glasses; standing case; key; objective adaptors (4); and watch keys (2)
Object number: 1999-1-0020a
English
Date: 1715-1720
Accessories: solar filter; lens; awl; dust caps.
Object number: 5002
See also/See also
