Pickering photographic sunshine recorder, afternoon half
Date: circa 1889
Inventory Number: 1996-1-0191
Classification: Sunshine recorder
Subject:
Inventor: William Henry Pickering (1858 - 1938)
User: Blue Hill Meteorological Observatory (1885-present)
Cultural Region:
City of Use:
Dimensions:
4.6 × 18.5 × 8.6 cm (1 13/16 × 7 5/16 × 3 3/8 in.)
Bibliography:
Blue Hill Meteorological Observatory: The First 100 Years---1885-1985
Description:
This is part of the photographic Pickering-model sunshine recorder. Essentially it is a pin-hole camera.
It consists of a metal compartment with the shape of a half cylinder with flat ends. One end has a metal, elongated v-shaped attachment, with notches along the bottom of the v. A metal tab on the flat side of the cylinder curves up to lock against the notches in the v, which hold the tab in position. The compartment is designed to hold a piece of photographic paper, which is exposed to solar radiation through small holes on the flat side of the recorder compartment.
It consists of a metal compartment with the shape of a half cylinder with flat ends. One end has a metal, elongated v-shaped attachment, with notches along the bottom of the v. A metal tab on the flat side of the cylinder curves up to lock against the notches in the v, which hold the tab in position. The compartment is designed to hold a piece of photographic paper, which is exposed to solar radiation through small holes on the flat side of the recorder compartment.
Signedunsigned
FunctionA sunshine recorder, which measures the amount of solar radiation admitted to an opening in the instrument's main compartment, recorded on piece of photographic paper inside the compartment.
Historical AttributesAccording to the Annals of the Astronomical Observatory of Harvard College, volume 30 (1896), which is devoted to observations at the Blue Hill Meteorological Observatory from 1889 until 1890, W. H. Pickering invented this form of photographic sunshine recorder in about 1888 by modifying the Jordan version. It solved the problem of positioning the recorder in a place that would capture both the morning and afternoon sun, but dividing the instrument in half.
The new Pickering recorder was made in two parts, each being a half cylinder with its axis parallel to the earth's axis. Each semi-cylinder contained blue print paper, on which the sun acted by shining through holes in the flat side of the semi-cylinder. The holes moved down each day, so that one sheet of paper could last for a week. One of the semi-cylinders was positioned to record the morning sun; the other, the afternoon sun. If necessary, they could be placed on opposite sides of a house.
TheBlue Hill Meteorological Observatory installed W. H. Pickering's new version in 1889. It replaced the older Jordan device at the station. Many ther meteorological stations installed Pickering's sunshine recorder too. On the Blue Hill inventory, this item is listed as BHO #60: "Pickering model sunshine recorder. Made for use on five successive days. (For noon-sunset only, other half-item 60b.)"
The new Pickering recorder was made in two parts, each being a half cylinder with its axis parallel to the earth's axis. Each semi-cylinder contained blue print paper, on which the sun acted by shining through holes in the flat side of the semi-cylinder. The holes moved down each day, so that one sheet of paper could last for a week. One of the semi-cylinders was positioned to record the morning sun; the other, the afternoon sun. If necessary, they could be placed on opposite sides of a house.
TheBlue Hill Meteorological Observatory installed W. H. Pickering's new version in 1889. It replaced the older Jordan device at the station. Many ther meteorological stations installed Pickering's sunshine recorder too. On the Blue Hill inventory, this item is listed as BHO #60: "Pickering model sunshine recorder. Made for use on five successive days. (For noon-sunset only, other half-item 60b.)"
Primary SourcesAnnals of the Astronomical Observatory of Harvard College...Vol. XXX. Observations Made at the Blue Hill Meteorological Observatory, Massachusetts, U.S.A., in the Years 1889-1990 (Cambridge, 1896), 30: vii. online here.
ProvenanceBlue Hill Meteorological Observatory.
Published ReferencesJohn H. Conover, The Blue Hill Meteorological Observatory: The First 100 Years - 1885-1985 (American Meteorological Society, 1990), Appendix B, p.37, no. 60.