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Frederick Eckel Y level

Datecirca 1885

Inventory Number5151a

ClassificationSurveyor's Level

Subject

Maker Frederick Eckel 1835 - 1898

Seller Ledder & Probst 1906-1920s

User Department of Engineering Sciences, Harvard University founded circa 1918

Cultural Region

Place of Origin

Place of Use

Dimensionslevel: 25 × 14.9 × 43.8 cm (9 13/16 × 5 7/8 × 17 1/4 in.)
case: 16.8 × 58.7 × 19.2 cm (6 5/8 × 23 1/8 × 7 9/16 in.)

Material

Accessoriesmahogany case (top very worn); lens hood; sunshade; tripod, see 5151b

DescriptionBrass Y level with gunmetal finish consisting of the following major components (from top to bottom): telescope tube in two Y supports; spirit level with attached scale; foot plate with four leveling screws.

The telescope tube has a knurled eyepiece. Clamped around the tube are two brass rings that protect the tube from contact with the Y supports. Clamped around the tube between the Y supports near the eyepiece end are two additional rings, with four brass pins projecting from each. Bolted to the top of the tube between the Y supports near the objective end is a single knurled knob.

Each Y support is held closed by a brass pin having a loop at one end. A piece of string threaded through each knob ties it to the respective end of the level bar.

A spirit level is suspended from two brass posts projecting down from the telescope tube. The spirit level has two semi-oval windows. Bolted to the top of the spirit level tube, perpindicular to the windows, is a long silver (?) tab printed with two scales. The leftmost scale has values descending from 18 to 2. The scale on the right has values ascending from 2 to 18.

Below the level bar is a circular foot plate. Four leveling screws project down from a second brass disc before coming to rest on the foot plate. Around the center of each screw is a circular knurled knob.

Above the top brass disc are three knobs. One circular knurled knob sits close to the vertical spindle. The two knobs below this, one key-shaped and one circular with knurling, project out horizontally from the vertical spindle. The latter is also bolted to the top disc.

The Y level is stored in a mahogany case. Also in the case are a sunshade and lens hood.

See also the tripod for this level, 5151b.

Signedengraved on instrument support: F. ECKEL / NEW YORK / 1078

Inscribedengraved on case lid: Y. LEVEL / 24 / PROPERTY OF / HARVARD COLLEGE / 24 L; partially removed label on case (almost illegible): 18 [or 13, or 48, or 43]; card pinned to inside of case lid: ECKEL LEVER SERIES 1078 / (around circle) SOLD BY / (in circle) L.P. / QUALITY, EFFICIENCY, RELIABILITY; card pinned on previous card: LEDDER & PROBST INC. / SURVEYING / INSTRUMENTS / DRAWING / MATERIALS / REPAIRING / BLUE AND BLACK PRINTING / 56 FRANKLIN STREET / BOSTON, MASS.;

Curatorial RemarksTag: Erect / unusual / base This is level 24 in a series of at least twelve levels once belonging to Harvard's Department of Engineering. (CHSI has levels numbered 2, 3, 6, 7, 8, 12, 14, 19, 20, 21, 22, 24.)

FunctionFor use in surveying, to measure contours.

After placing the Y level on a tripod (see 5151b) at his starting location, the user levels the instrument by means of the spirit level and the leveling screws. 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.

ProvenanceDepartment of Engineering, Harvard University, level 24. Received October 1961. No Harvard University tag.