Sundial by Copp Family, United States, ca 1750 — view 1 of 2 — View 1 of 2 · Image: National Museum of American History · original image source

View 1 of 2 · Image: National Museum of American History · original image source

Instruments · Sundial

Sundial by Copp Family, United States, ca 1750

DocumentedDocumented from the holding institution's catalogue record.

Maker / attribution: Copp Family (Associated Name)
Date: ca 1750
Historical period: Precision & Scientific Horology (1750 – 1850)
Country of origin: United States
Place: United States: New England; United States: Connecticut; United States: Massachusetts; United States: Rhode Island; United States:…
Object type: Sundial
Dimensions: pewter (overall material); overall: 1 5/8 in x 3 in; 4.1275 cm x 7.62 cm
Holding institution: National Museum of American History, Smithsonian Institution, Washington DC
Accession / object no.: DL.006505
Credit line: Gift of John Brenton Copp
Catalogue title (original): Sundial

Record summary

Held and catalogued by National Museum of American History, Smithsonian Institution, Washington DC (object number DL.006505), this is a sundial by Copp Family, made in United States: New England; United States: Connecticut; United States: Massachusetts; United States: Rhode Island; United States:…, dated ca 1750. The Atlas places it in the Precision & Scientific Horology period (1750 – 1850) of its Instruments collection. Recorded dimensions: pewter (overall material); overall: 1 5/8 in x 3 in; 4.1275 cm x 7.62 cm. The record is illustrated with 2 photographs.

Assembled from the source record's structured fields. Dates and attributions are given as the source states them; where a field is missing the Atlas leaves it blank rather than estimating.

Catalogue description

Description

The Copp family of Stonington, Connecticut used this pewter sundial around 1785. The dial has three holes to mount the sundial horizontally, with the initials “NM” cast at the clocks’ “6” position. Accurately aligning the tip of the sundial’s gnomon to true north allows the gnomon’s shadow to fall on the hour of the dial plate. The NM is possibly Nathan Miller from Rhode Island, the son of founder Josiah Miller, whose name appears on several similar sundials of the era.

Description

The Copp Collection contains a variety of household objects that the Copp family of Connecticut used from around 1700 until the mid-1800s. Part of the Puritan Great Migration from England to Boston, the family eventually made their home in New London County, Connecticut, where their textiles, clothes, utensils, ceramics, books, bibles, and letters provide a vivid picture of daily life. More of the collection from the Division of Home and Community Life can be viewed by searching accession number 28810.

Historical context

Precision & Scientific Horology (1750 – 1850)

Harrison solves longitude; Mudge invents the lever; Breguet's Paris workshop defines the modern watch.

The longitude problem was solved by the marine chronometer and lunar distance methods; dividing engines made precision scales possible, and observatories set time by transit instruments.

Read the period in the timeline More instruments from this period Earlier: Early Modern Horology

Atlas type guide

Sundials and solar time-finders

A sundial tells time from the position of a shadow cast by a gnomon or style. Because the sun's apparent motion depends on latitude, every fixed dial is laid out for a particular latitude, and portable dials either carry a latitude scale or are made for one region. Sundials show local apparent solar time, which drifts against mean (clock) time by up to about sixteen minutes over the year — the equation of time.

Portable dials were the pocket instruments of the sixteenth to eighteenth centuries. Nuremberg and Augsburg workshops produced folding ivory diptych dials with inset compasses; English and French makers sold brass horizontal dials, ring dials and the Butterfield type; Japanese and Chinese makers had their own traditions of compass dials. After mechanical watches became reliable, dials remained in use for setting them, and nineteenth-century heliochronometers were built to correct directly for the equation of time.

What to look for

The latitude engraved on the dial plate or a latitude arc on the gnomon — it shows where the dial was meant to be used.
The type of hour lines: equal (equinoctial) hours, Italian or Babylonian hours counted from sunset or sunrise, or unequal temporal hours on early and Islamic instruments.
An inset magnetic compass and whether a magnetic-declination mark is drawn on its card — a useful dating clue because declination changes over time.
Maker's signatures and town marks: Nuremberg compass-makers (Kompassmacher) often struck a personal mark and the town's punch.
Additional scales such as lunar volvelles, wind roses, perpetual calendars or lists of cities with their latitudes.

Dating clues

Ivory diptych dials are characteristic of Nuremberg between about 1500 and 1700.
Butterfield-type dials with a bird-shaped adjustable gnomon point to Paris workshops from the late seventeenth century onward.
Equation-of-time tables engraved on the plate became common after the mid-seventeenth century, once pendulum clocks made the difference between solar and mean time obvious.

General guidance written by the Atlas editors about this kind of object. It is not a statement about this particular piece; for that, rely on the source record above and on physical examination.

Mechanisms mentioned

No escapement or complication is named in the source record. See the encyclopedia for how such pieces work.

Record completeness

Maker or attributionRecorded
DateRecorded
Place or countryRecorded
MaterialsNot in source
DimensionsRecorded
Narrative descriptionRecorded
Inscriptions / marksNot in source
ProvenanceNot in source
Several photographsRecorded

Editorial status: Documented — facts as published by the source; not independently verified by Atlas editors.

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Sources & image rights

Record source: National Museum of American History, Smithsonian Institution, Washington DC.

Image rights: CC0 1.0 (Smithsonian Open Access).

Images are hosted by the Atlas for study and credited to their owner. Rights holders may request correction, credit changes or removal via the editorial office.

Cite this record

"Sundial by Copp Family, United States, ca 1750." National Museum of American History, Smithsonian Institution, Washington DC, DL.006505. Catalogue record in The Horology Atlas, WatchMuseum.org, https://atlas.watchmuseum.org/museum/sundial-by-copp-family-united-states-ca-1750-7fdf7e.