The artwork
Study of Sky and Trees
oil on paper · Height: 24.8 cm (estimate); Width: 30.5 cm (estimate)
No museum image is reproduced here.
View the museum objectJohn Constable · Victoria and Albert Museum · 167-1888
Study of Sky and Trees
“Sepr. 24th . . 10 o'clock morning wind S.W. warm & fine till afternoon, when it rained & wind got more to the north”
Museum transcription. Source record. Each underlined phrase links to its claim.
The inscription gives 24 September but no year. The V&A catalogue supplies 1821; the register comparison uses that attribution.
Finding · Nephos analysis · version 2026-09-09
Constable writes SW; Howard records W, an adjacent direction. Howard’s note is “Overcast.” It does not establish the change from a warm, fine morning to afternoon rain or a turn of the wind towards north.
The Nephos method
How this study was read
The method in fullWhat is written
Hampstead, 24 September 1821, 10 o'clock morning.
Sepr. 24th . . 10 o'clock morning wind S.W. warm & fine till afternoon, when it rained & wind got more to the north
Victoria and Albert Museum, 167-1888, as the museum transcribes it
Records of those days
- Luke Howard’s registerPrinted daily wind, thermometer and notes, The Climate of London. Kept at Tottenham or Stratford, not Hampstead.
- 20th Century ReanalysisA modern reconstruction for a 1° cell about 111 by 68 km, estimated from pressure, not observed.
Each claim tested
- “Sepr. 24th” The inscription gives 24 September but no year.
- “10 o'clock morning” The computed Sun describes the light available at an assumed place and hour.
- “wind S.W.” SW and W are adjacent sectors, not identical readings.
- “warm & fine till afternoon,” Howard records “Overcast” and daily thermometer extremes.
- “when it rained” Howard’s note says “Overcast,” without reporting an afternoon shower.
- “wind got more to the north” One daily direction cannot establish a within-day change at another place.
Verdict
Constable writes SW; Howard records W, an adjacent direction.
- Partially agrees“wind S.W.”
- Unknown“Sepr. 24th”, “10 o'clock morning”, “warm & fine till afternoon,”, “when it rained”, “wind got more to the north”
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 | Howard registerPrinted table · Source | Weather reconstruction20th Century Reanalysis · Source | The sunComputed · Hampstead assumed · Source | Verdict and limit |
|---|---|---|---|---|
| “Sepr. 24th” Unknown |
The register has an entry for this day. Nothing in it names a painter. Page image | — | — | The inscription gives 24 September but no year. The V&A catalogue supplies 1821; the register comparison uses that attribution. No independent source assembled here dates the painting. Link to claim |
| “10 o'clock morning” Unknown |
— | — | 33.0° altitude · 146.1° azimuthAt 10:00 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 |
| “wind S.W.” Partially agrees |
WPage image | Wind from 34° · 0.6 m/s; 68 ± 37% cloud; 14.0 ± 2.3°C09:00 UTC; a regional cell, about 111 × 68 km. Mean and one-sigma spread. Query sources. | — | SW and W are adjacent sectors, not identical readings. Howard’s daily direction is from another place and cannot establish the later turn towards north. Link to claim |
| “warm & fine till afternoon,” Unknown |
66° / 44°FPage image | Wind from 34° · 0.6 m/s; 68 ± 37% cloud; 14.0 ± 2.3°C09:00 UTC; a regional cell, about 111 × 68 km. Mean and one-sigma spread. Query sources. | — | Howard records “Overcast” and daily thermometer extremes. Neither defines “warm” or establishes fine conditions at the easel during the morning. Link to claim |
| “when it rained” Unknown |
“Overcast.” Note page image. | — | — | Howard’s note says “Overcast,” without reporting an afternoon shower. That does not establish or exclude rain at the painter’s position. Link to claim |
| “wind got more to the north” Unknown |
WPage image | — | — | One daily direction cannot establish a within-day change at another place. 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.
Howard · 24 September 1821
The printed register
W · 66° / 44°F
Wind and first thermometer, maximum/minimum for 24 September 1821. Page image.
“Overcast.” Note page image.
The table does not establish conditions at Constable’s position. Supplementary Tottenham observations are kept separate from the main register.
The computed sun
33.0° altitude · 146.1° azimuth
At 10:00 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 34° · 0.6 m/s; 68 ± 37% cloud; 14.0 ± 2.3°C
09:00 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
- Hampstead The exact easel coordinates are not established; the solar comparison uses the assumed Hampstead position.
- Date evidence
- The inscription gives 24 September but no year. The V&A catalogue supplies 1821; the register comparison uses that attribution. 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 167-1888. 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 and Trees, 167-1888. Object page; museum transcription. The museum qualifies Hampstead as probable and also transcribes the monogram JC.
- H1Luke Howard, The Climate of London, 2nd edition, vol. III (London: Harvey and Darton, 1833); Table CLXXXIV, p. 60; continuation and results, p. 61 Page image. Printed monthly results.
- 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