The artwork
Study of sky effect
Pencil and watercolour · Height: 189 mm; Width: 229 mm
No museum image is reproduced here.
View the museum objectJohn Constable · Victoria and Albert Museum · 202-1888
Study of sky effect
“26 Sepr 1833 12 to 1--noon looking North East”
Museum transcription. Source record. Each underlined phrase links to its claim.
The V&A transcribes 26 September 1833, 12–1, looking north-east. The solar calculation uses the interval’s midpoint, 12:30 local mean time, as an assumption.
Finding · Nephos analysis · version 2026-09-09
The Royal Society records S at 9 a.m. and “Fine—nearly cloudless” for the day. Constable’s inscription makes no weather claim to compare with those entries. Its date, noon interval and north-east view remain unknown to the independent witnesses.
The Nephos method
How this study was read
The method in fullWhat is written
great britain, 26 September 1833, 12 to 1--noon.
26 Sepr 1833 12 to 1--noon looking North East
Victoria and Albert Museum, 202-1888, as the museum transcribes it
Records of those days
- Royal Society meteorological journalThe Society’s own daily register, kept in London.
Each claim tested
- “26 Sepr 1833” The V&A transcribes 26 September 1833, 12–1, looking north-east.
- “12 to 1--noon” The computed Sun describes the light available at an assumed place and hour.
- “looking North East” No independently identified landmark or measured painted solar direction fixes the painting’s bearing.
Verdict
The Royal Society records S at 9 a.m.
- Unknown“26 Sepr 1833”, “12 to 1--noon”, “looking North East”
01 · The evidence
The claims and their witnesses.
Each phrase of the inscription is a claim. Each column is a witness that never saw the painting, with its own place, scale and limit.
How to read itRead across one row: the phrase Constable wrote, what each witness can say about it, and the verdict on the right. A dash means that witness has nothing to offer on that claim.
| Claim | Royal Society registerPrinted table · Source | Weather reconstruction20th Century Reanalysis · Source | The sunComputed · Hampstead assumed · Source | Verdict and limit |
|---|---|---|---|---|
| “26 Sepr 1833” Unknown |
The register has an entry for this day. Nothing in it names a painter. Page image | — | — | The V&A transcribes 26 September 1833, 12–1, looking north-east. The solar calculation uses the interval’s midpoint, 12:30 local mean time, as an assumption. No independent source assembled here dates the painting. Link to claim |
| “12 to 1--noon” Unknown |
— | — | 36.5° altitude · 192.2° azimuthAt 12:30 local mean time; Hampstead assumed. Computation. | The computed Sun describes the light available at an assumed place and hour. No independently identified landmark or measured painted solar direction establishes the time of execution. Link to claim |
| “looking North East” Unknown |
— | — | 36.5° altitude · 192.2° azimuthAt 12:30 local mean time; Hampstead assumed. Computation. | No independently identified landmark or measured painted solar direction fixes the painting’s bearing. The solar position alone cannot establish the stated view. Link to claim |
Described. Words used by a person in a particular context: the inscription and the printed register. A felt quality cannot be converted into a threshold, and strength words have no shared numerical scale.
Modelled. A reconstruction describes a regional cell. It is not an observation at the easel. No weather agreement independently establishes a painting's date.
02 · The witnesses
What each source can reach.
Royal Society · 26 September 1833
The printed register
S · 63.7° / 54.2°F
Wind at 9 a.m. mean time; external self-registering thermometer, Highest/Lowest for 26 September 1833. Page image.
“Fine—nearly cloudless.” Note page image.
Royal Society apartments, Somerset House, London. Wind at 9 a.m. mean time. External self-registering thermometer, Lowest and Highest in Fahrenheit; these are not Howard’s first-thermometer readings.
No printed wind tally exists on this page. The tally computed from its daily 9 a.m. column is: ESE 4, SW 5, SSW 4, NE var. 4, NNE 1, SE var. 1, NNW 2, ENE 3, E 2, NW var. 1, S 2, WSW 1. A second separate page-image reading, from bottom to top, agreed on all 30 entries. Both passes were made by the same reader; no second-person review is claimed.
The computed sun
36.5° altitude · 192.2° azimuth
At 12:30 local mean time; 51.560° N, 0.165° W is an assumed Hampstead position. No cited source establishes the clock basis; local mean time there trails UTC by about 40 seconds.
A solar calculation supplies no observation of the painting's execution. No painted angular measurement is established here.
Weather reconstruction
Regional context
Wind from 224° · 4.3 m/s; 62 ± 36% cloud; 15.7 ± 2.0°C
12:00 UTC at 52° N, 0° E. Wind speed and bearing calculated from the mean u/v components; component spreads are retained in the query sources. Cloud and temperature show mean and one-sigma spread. This is a 1° cell about 111 × 68 km. No local wind-strength scale or capture cloud measurement is established here.
03 · Making the artwork
The sky passed through an artist's decisions.
Production uncertainty is separate from weather uncertainty. The located sources do not establish every stage of this object's making, and “unknown” is not evidence that a stage did not happen.
- Locationpartly known
- great britain The exact easel coordinates are not established; the solar comparison uses the assumed Hampstead position.
- Date evidence
- The V&A transcribes 26 September 1833, 12–1, looking north-east. The solar calculation uses the interval’s midpoint, 12:30 local mean time, as an assumption. Museum source.
- Outdoor executionunresolved
- The evidence assembled here does not establish that every passage was executed outdoors in the stated interval.
- Preparatory work and later changesunknown
- No complete sequence or timing of working sessions is established by the sources assembled here. No technical examination of this object is offered.
04 · Revisions
How the reading changed.
- Sources assembled
- The museum transcription is placed beside the independently dated register and modelled context. Catalogue qualifications remain explicit.
- What remains open
- This is the first Nephos record for this object. No earlier verdict is being revised.
05 · Take this into your work
A record you can cite, print or embed.
Cite individual claims by their link, and cite museum and historical sources directly when using their statements. Nephos analysis is independent of the holding institution; image licences are separate from the research text.
Machine-readable
For the Victoria and Albert Museum: this record is for 202-1888. If it is right, link it from your object page; if anything is wrong, write to Nephos and it will be corrected the same day.
The museum’s catalogue remains the authority. Nephos does not claim endorsement.
06 · Sources
Follow every claim.
- M1Victoria and Albert Museum: John Constable, Study of sky effect, 202-1888. Object page; museum transcription. The museum also transcribes J. Constable in pencil.
- H1Royal Society, Meteorological Journal for September 1833, Philosophical Transactions of the Royal Society of London (1834); Meteorological Journal for September, 1833; unnumbered monthly table Page image.
- S1Skyfield 1.55 with JPL DE440. Apparent topocentric Sun without atmospheric refraction. The place and clock basis are assumptions; the calculation is recorded in the JSON-LD record.
- R1NOAA-CIRES-DOE 20th Century Reanalysis v3. tcdc mean · tcdc spread · uwnd mean · uwnd spread · vwnd mean · vwnd spread · air mean · air spread