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Tyndall-John: central claims

Project: John Tyndall's radiant-heat, gas-absorption and atmospheric-vapour work (1859-1892), from five of his own books and papers in source folder: Tyndall-John. Compiled from the digests and deep reads; no verdicts. Tags: [read] from the documents, [memory] recalled (confidence given).

Source note (limits, not a full source gap)

The key works are readable: all five PDFs have an OCR text layer (554 of 555 pages of Heat, 520 of 521 of New Fragments, 304 of 305 of Six Lectures, 58 of 59 of On Radiation, 24 of 26 of the 1866 paper) and every number a claim turns on was checked on rendered page images by the deep readers. Limits a later step should repeat: - Everything in the folder is by Tyndall himself. No independent replication, critique (Magnus, Melloni, Herschel, Strachey, Kirchhoff, Balfour Stewart, etc.) or later account is in the folder; the Investigator must supply it. Tyndall's descriptions of his own priority (calorescence, water-vapour absorption, the diamond burnt by a terrestrial source) are those of an interested party. - "On Calorescence" (1866) lacks journal p.1 (the introduction with the Herschel and Muller solar curves, Figs. 1-2) and all of Plate I except a fragment; Heat's plates (Plate I apparatus) and figures are not in the text; Six Lectures Fig. 56 (the spectrum curve) is not legible. - After the QE deep reads (2026-10-09) Heat chapters XI (paras 435-466), XII, XIII and XIV (paras 647-684), and the Magnus conduction passage (pp.250-254, p.533), are deep-read with tables checked on page images. Still covered by digest only: Heat chapters I, IV, V, VII (apart from the Magnus passage), VIII and the spectrum-analysis paragraphs 663-680 (PDF pp.495-503), which are peripheral to the seven claims. Recommended further deep reads only if a verdict turns on them: Heat Ch. VIII PDF pp.255-282 (reflection of obscure heat, "rays of cold"); Six Lectures Lecture XI blue-of-sky PDF pp.179-188 (Sonnet). - The Heat Ch. XIV meteorological data (Wells, Glaisher, Pouillet, Melloni) are other people's and carry no humidity measurement; the vapour step in claim 2 is carried by Tyndall's laboratory absorption data and his own inference (the Bengal "dry-air supplement", para 655). The Titlis (1866) spectroscope observation of Janssen's water-vapour bands is a bare mention with no result (New Fragments p.472). - Several single figures (the "ten-foot column intercepts 10-15 per cent", the "two-inch ether shell intercepts 35 per cent", "water 1/10 inch passes the sun's rays", the Sahara frost, the "most delicate experiments" on ice stretching, the "distinguished authority" on elementary molecules, the Strachey series) are stated without an experimental record or a named source in the folder; they are reported as Tyndall's statements, not discarded. - Tyndall's Titlis observation (1866) of Janssen's vapour bands is reported without a result. - Mayer's own paper is not in the folder; Tyndall's 771.4 is his reconstruction of Mayer's method (paragraphs 82-83, 92).

The 3-7 central claims (one sentence each)

  1. Oxygen, nitrogen, hydrogen and dry air are practically transparent to radiant (infrared) heat, while compound gases and vapours (CO2, ammonia, nitrous oxide, olefiant gas, water vapour, ether) absorb it from tens to thousands of times more strongly, measured with a compensated thermopile and rock-salt windows (at 1 inch pressure: CO2 972, ammonia 5,460, olefiant gas 6,030 times air, with the air value assumed at 1 degree of 30), and a gas's radiating power equals its absorbing power.
  2. Atmospheric water vapour, far more than the dry air carrying it (70-90 times per unit amount), controls how fast the earth loses heat: it is a "blanket" or "dam" that keeps the surface warm, at least 10 per cent of terrestrial heat is intercepted within ten feet of the ground, and nocturnal cooling, frost, desert and mountain temperature ranges and tropical rain depend on it; CO2 is named only as a minor, weaker constituent.
  3. The invisible (extra-red) radiation of an intensely luminous source is several times its visible radiation (electric arc: 7.7 by spectrum area, 8 by filter subtraction; the sun about 2), and a solution of iodine in bisulphide of carbon removes all visible light while passing most of the heat, so the dark rays can be focused to ignite combustibles and make platinum and carbon glow.
  4. That glow is a transmutation of heat-rays into rays of higher refrangibility ("calorescence"), the reverse of Stokes's fluorescence rule, with the unresolved sub-claim that certain blue glasses make the platinum glow pink (a possible gap in the calorescent spectrum) which Tyndall himself asks to have confirmed.
  5. Absorption of radiant heat is a property of the individual molecule, selected by resonance between the wave period and the periods of the atoms in the molecular group (and by molecular shape and complexity), and it is unchanged when the same number of molecules is compressed into a shorter tube or condensed from vapour to liquid ("conservation of molecular action", "thermal continuity of liquids and vapours").
  6. Radiant heat and light are the same kind of ether wave motion, differing only in period, shown by reflection, total reflection, invisible images, polarization, double refraction and magnetization of dark heat, and heat generally is a mode of motion (Rumford's cannon boring, Davy's ice, the mechanical equivalent 772 ft-lb per lb per degree F with Mayer's method reconstructed to 771.4).
  7. Glacier ice moves without being viscous under tension, because broken ice refreezes at its contacts (regelation), and the Ice Age glaciers show the action of abundant vapour and strong solar heat followed by effective condensation, not a weaker sun (Heat Ch. VI).

Notes on deduplication: the water-vapour/atmosphere argument occurs in On Radiation (1865), Heat Ch. XI (1868) and New Fragments (1882); the 7.7/8 ratio and the iodine filter in 1866, 1865, 1868 and 1872-73; the Rumford cannon-boring in Heat (twice) and New Fragments.

Specific testable statements worth tracking (from the deep reads, with source)

  • Absorption table at 1/30 atmosphere (On Radiation, copper-plate source): air 1, CO 750, CO2 972, HCl 1005, NO 1590, N2O 1860, H2S 2100, NH3 5460, olefiant gas 6030, SO2 6480 [read: On_radiation p.22-23, page image]. Heat Ch. X gives the same values at 1 inch Hg with a hotter Bunsen-plate source and adds chlorine 60, bromine 160 [read: Heat p.349-350].
  • At 30 inches (one atmosphere): CO2 90, CO 90, N2O 355, H2S 390, marsh gas 403, SO2 710, olefiant gas 970, ammonia 1,195 [read: Heat p.347-348].
  • CO2 absorption vs pressure for a CO-flame source: 48.0, 55.5, 60.3, 65.1, 68.6, 74.3 per cent at 1, 2, 3, 4, 5, 10 inches Hg; olefiant gas 23.2 ... 65.5 [read: Heat p.431, page image].
  • Water vapour: 72 times (48 degrees = 72 units), 70 times (7 site samples), 90 times (distilled-water-humidified purified air), 16,000 per molecule (80 x 200); 7.9 per cent absorbed in a 4 ft 3 in open tube; over 10 per cent in a 4 ft polished tube [read: Heat p.380-388, 401].
  • Strachey, 4-25 March 1850: vapour tension 0.888 ... 0.435 inch against night fall 6.0 ... 16.5 degrees [read: Heat p.391 page image]; Martins and Bravais 24 F versus 10 F [read: Heat p.393-394].
  • Arc spectrum: 44.6 per cent of the maximum already at the extreme red; invisible/visible 7.7 (area) and 8 (filter); iodine cell absorbs 11-13.2 per cent; bisulphide transmits 94.8 per cent at 2 inches [read: 1.full p.5-11].
  • Heat vs rays "Dark/Light": the visible rays of the electric light give "one-ninth" of the heat of the invisible rays at a focus (On Radiation p.26-28) which is the same ratio as 11:89.
  • Mayer-method equivalent 771.4 from 2,160 / 2.8, which becomes about 769 with unrounded intermediates and about 797 with the modern ratio of specific heats 1.40 [read: Heat p.97-99; reader arithmetic].
  • Breath CO2 by radiant-heat absorption versus Frankland's chemistry: On Radiation (1865) prints two pairs, physical 4.58 vs chemical 4.66 and 5.22 vs 5.33 per cent [read: On_radiation p.50, page image]. Heat (1868) prints three pairs, chemical / physical: 4.311 / 4.00, 4.66 / 4.56, 5.33 / 5.22 [read: Heat p.433, page image]. The first pair differs by 7 per cent; the other two by about 2 per cent. Tyndall: "very fair".
  • Hydrogen-flame series (Heat paras 530-534, 4 ft polished tube): undried laboratory air absorbed 17.2 per cent of a hydrogen flame's radiation (20.3 per cent on a later humid day), 0 for dry air; only 5.8 per cent of a glowing platinum spiral (one-third) and 8.6 per cent of the spiral plunged in the flame. Humidity, drying method and repeats are not stated [read: Heat p.428-429, page images]. In Tyndall's own data the same few feet of air absorb about 6 to 20 per cent depending on the source, which bears on the "at least 10 per cent within ten feet" figure (his own scaling of 10 per cent in 4 ft is about 23 per cent in 10 ft, a floor-type extrapolation that saturation and a cooler source could change) [calc].
  • Liquid versus vapour (claim 5): with equal quantities of matter, ten liquids and their vapours share one rank order for a red-hot platinum spiral source, and water vapour could not be tested unmixed with air (Heat paras 512-515, p.418). The order of vapours changes with the source (chloroform / iodide of methyl, formic / sulphuric ether). Printed inconsistencies in the book are kept in the record (see deep read): formic and sulphuric ether values swapped between p.416 and p.423, hydrogen-flame water transmission 2.8 on p.434 against 5.2 on p.436 for 0.04 inch.
  • Reciprocity (claim 1): rank order of dynamic radiation and absorption agrees in all 11 vapour pairs (ratios 0.40-0.61) and in 2 gas pairs; proportionality is rough, single runs, no errors given (Heat paras 446-466 and Ch. X pairs). Ozone from electrolysis absorbs 20 to 136 times the carrying electrolytic oxygen, its amount unmeasured (paras 440-445). Perfumes: patchouli 30 ... aniseed 372 times air (para 438 prints thyme 74 where the table has thyme 68).
  • Planetary atmosphere: 1 inch of olefiant gas absorbs at least 26 per cent (measured value quoted in a different context, no source or apparatus given); a 2 inch layer of air saturated with ether vapour "would cut off fully 35 per cent" of planetary radiation ("I find"; no table, source or temperature in the folder) (Heat paras 545-546, p.434-436).
  • Luminous fractions (Heat paras 583-587): white-hot platinum 1 part in 24 (the same chapter's table gives 4.6 per cent absorbed, about 1 in 22), gas flame 1 in 25, electric light 1 in 10 and, later, 11 per cent absorbed (so "eight times") [read: Heat p.457-459, page images]. Tyndall tests Melloni's alum assumption: concentrated alum transmits 20 per cent of the iodine-filtered obscure heat (paras 641-643), correcting Melloni's alum-based ratios, not Tyndall's iodine or prismatic figures. The sun's "invisible about twice the visible" is Muller's ratio at the ground, after atmospheric absorption. Ox-eye: one fifth of the electric light's obscure rays reach the retina (para 643, single report). The only dated solar trial is 15 November 1864.
  • Dew and atmospheric absorption of sunlight (Heat Ch. XIV): Wells 1818 (grass thermometer 12 F below the air, only 2 F when cloud passes), Glaisher's chilling by height (long grass 1000, one foot 129, six feet 52; the OCR's 670 and 62 are errors for 570 and 52), Pouillet's swansdown (7.1 C in April, 7.21 C in June), Melloni's 2 C limit. Pouillet's 25 per cent (zenith) and 40 per cent (hemisphere) absorption of sunlight is solar, not terrestrial, and the attribution to vapour is Tyndall's inference [read: Heat p.486-506].
  • Magnus: hydrogen "conducts heat like a metal" (Magnus); "the experimental question of gaseous conduction is still an open one" (Tyndall, Heat p.254); a later Magnus paper against the vapour results is noted without content or reply (Heat p.533). Tyndall also concedes priority on singing flames to Count Schaffgotsch (Heat p.293, digest).

Corrections to earlier documents

The digests are expected to contain OCR errors; the deep reads corrected them from page images. The orchestrator should apply these to any stale copy (digests, summaries, reviews): - On Radiation: nitric oxide is 1590 (not 1890; Heat OCR "1690" also an OCR error, Heat image value 1590 per the Heat deep read); olefiant gas 6030 (not 6080); aniseed 372 (not 872); carbonic oxide 750; amylene 321 (not 821); formic ether 548. Digest On-radiation part 01 p.23, p.38, p.40 carry the wrong values. - Heat digest corrections (Heat deep read section 11): digest .10 p.335 olefiant gas table (1 inch = 90, 4 = 157, 8 = 186, 10 = 193); digest .11 p.348 "50 inches" should be 30 inches; digest .11 p.350 nitric oxide 1590; digest .11 p.358 valeric ether 32 (not 82); digest .11 p.357 boracic ether 1/10 inch (not 1/4 inch); Heat Rumford water-box was 18.77 lb "2 1/2 gallons" (not 24 gallons). - 1866 paper: the 2-inch bisulphide-cell readings are 74 degrees (empty) and 73 degrees (filled), repeat 73 and 72, not "73.8" (digest 1-full .01 p.10; Heat digest p.456 "73"); the flask distance is 3 1/2 feet and the flask 6 3/4 inches, not "34 feet" and "63 inches" (digest p.19); iodine cell 1.2 inch (not "1-2 inch"); glass cell sides "nearly 2 1/2 inches" (not 23). Digest Heat p.457-458 values "739 / 73" and "720 / 70.0" are OCR-garbled decimals. - Six Lectures: Faraday's magnetization of light is Lecture IV section 8, PDF pp.172-173 (printed pp.145-146), not Lecture V; the "pp.172-173" in the task statement refers to PDF pages. The comet and diamond passages are printed pp.171-173 (PDF pp.198-200). - Rumford cannon-boring: 107 is the water temperature after one hour (Fahrenheit), not a final result; the 23.5-versus-28-minute result is the goldbeater's-skin vessels (not cannon boring) and measures the coating, not colour (New Fragments deep read E). - Mayer: Tyndall states Mayer's first paper contains no details of the calculation; 771.4 is Tyndall's reconstruction, not Mayer's own number. - QE deep reads (2026-10-09), Heat. Breath table: Heat's first chemical value is 4.311 (not 4.11 as the On Radiation deep read took from OCR) and its second physical value 4.56 (On Radiation prints 4.58); a real difference between the 1865 lecture and the 1868 book, not OCR. Breath pressures are 1, 3, 6 and 30 inches (not "6.5"). Digest Heat part 13 p.433 "6.22" is 5.22. - Glaisher table (Heat p.492): two inches above grass 570 (OCR 670), six feet 52 (OCR 62). - Perfume table (Heat p.364): spikenard 355 (OCR 855), sandal-wood 32 (OCR 382), neroli 47 (OCR "AT"). Dynamic vapour table (p.375): OCR "6.", "7.", "384", "48", "28" are 64, 70, 34, 43, 23. - Six Lectures p.215 page image shows 150 for the magnetisation of obscure heat ("equal to 150 of the lower degrees"); the digest's "may be 15" is wrong. - Claim 3: the 8 is 89/11 (para 587); the rounder "1 in 10" of para 586 would give 9. The sun's "about 2" is a ratio at the earth's surface (Muller). Pouillet's 25 and 40 per cent are solar absorption and are not the same kind of evidence as the "ten feet" terrestrial figure in claim 2. - Claim 2 wording ("at least 10 per cent ... within ten feet"): Tyndall's statement is a lower bound (Heat p.387 "no doubt at least 10 per cent"); extrapolations of his own 4 ft figures (about 23 per cent, or 38 per cent from the hydrogen flame) exceed it. The open questions are saturation, humidity (never stated) and the cooler terrestrial source, not contradiction by his own data.