{
 "schema": "nephos.method.v1",
 "slug": "thayer-winter-sunrise-monadnock-1917",
 "title": "Abbott Handerson Thayer, Winter Sunrise, Monadnock (1917), Met 17.180.1",
 "urls": [
  "/studies/thayer-winter-sunrise-monadnock-1917"
 ],
 "written": {
  "summary": "The Met dates this version to the third week of October 1917 from Emma Thayer’s letter. The study interprets that as 15–21 October: a window for execution, not a dated winter sunrise.",
  "items": [
   {
    "quote": "third week of October 1917",
    "source": "The Met’s object text and 1980 catalogue, describing Emma B. Thayer to John Gellatly, 26 November 1917. Original letter not inspected.",
    "url": "https://www.metmuseum.org/art/collection/search/12786"
   },
   {
    "quote": "my old theme",
    "source": "Thayer to George de Forest Brush, 6 January 1917, quoted in the Met catalogue, p. 102. Original letter not inspected.",
    "url": "https://cdn.sanity.io/files/cctd4ker/production/15bd0c79920937097b3316a939224159b1f0c453.pdf#page=143"
   }
  ]
 },
 "records": [
  {
   "name": "Keene daily high and low temperatures",
   "detail": "All 7 days present, quality flags blank; checked against the 1917 printed table. Daily extrema are not sunrise readings.",
   "url": "https://www.ncei.noaa.gov/pub/data/ghcn/daily/all/USC00274399.dly"
  },
  {
   "name": "New England climatological report, October 1917",
   "detail": "Keene reports 0 inches of snowfall for the whole month. The regional summary reports snow farther north on 12 October; Monadnock is not named.",
   "url": "https://www.ncei.noaa.gov/nerms/api/document/34AB3017348D48ABB4CB27E82B2AF0AB/download"
  },
  {
   "name": "Daily weather maps and a computed sunrise",
   "detail": "Albany and Boston sky symbols at 8 a.m. EST; Dublin sunrise computes to 06:01–06:08 EST. Different places and times.",
   "url": "https://library.oarcloud.noaa.gov/docs.lib/htdocs/rescue/dwm/1917/19171015.pdf"
  }
 ],
 "gaps": [
  "No verified summit snow or local sunrise cloud record.",
  "Dublin and Peterborough files contain no 1917 rows.",
  "The exact easel site, depicted day and horizon are unknown."
 ],
 "tests": [
  {
   "claim": "Does October rule out a winter subject?",
   "result": "No. The catalogue documents a recurring theme and studio variants. Execution and depicted season need not coincide."
  },
  {
   "claim": "Do the temperatures prove snow?",
   "result": "No. Keene reaches 22 °F, but frost temperatures do not establish snowfall or snow cover on Monadnock."
  },
  {
   "claim": "Can a clear sunrise be identified?",
   "result": "No. Clear symbols occur at both selected regional stations on 16, 17, 21 October, at a later hour. The mountain sky remains unknown."
  }
 ],
 "finding": "The week includes cold minima and clear regional mornings, but the records do not identify the painted sunrise or establish snow on Monadnock. The strongest explanation of the October/winter distinction is the documented history of a repeated subject.",
 "verdicts": [
  {
   "claim": "Snow on Monadnock in the execution week",
   "verdict": "Unknown",
   "reason": "Keene’s snowfall and regional snow reports do not measure the summit."
  },
  {
   "claim": "The painted sunrise",
   "verdict": "Unknown",
   "reason": "No depicted day, local sky observation or verified easel bearing."
  }
 ],
 "limits": [
  "The third week is interpreted as 15–21 October; the letter’s full wording has not been checked in the archive.",
  "The cold daily minima may precede the reporting date and are not timed observations of dawn.",
  "Solar times assume a level horizon; the mountain and intervening terrain can delay visible sunlight.",
  "A 1980 catalogue illustration is horizontally reversed relative to the current Met image. The current image is retained without flipping; no compass direction is inferred from it."
 ]
}