Kilner-Walter: Physicist review (Step 2)

Project: Walter J. Kilner, The Human Atmosphere (1911), the "aura" seen through dicyanin screens. Reviewer role: PhD physicist. I state the mainstream view, then judge each claim. Tags: [read] = from the documents (printed page numbers, PDF page minus 19, unless "PDF"); [web] = Internet source with URL; [memory] = recalled, with confidence. No source gap: the OCR of the 1911 book is readable throughout. The BMJ review of January 1912 could not be read (see section D), so any statement about it rests on Wikipedia alone.

What I read myself: PDF pp.24-27, 109-142, 149, 156-159, 314-318 of the project PDF; the whole deep read (Appendix, Cases 41-42); the Investigator's notes (sites.md, research/*.md). I did not re-read the 1920 second edition or Boddington 1931 beyond the Investigator's quotations.

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A. Corrections to Step 1

1. "Case 88 and Case 21 appear twice" (claims.md, internal oddities) is probably not an oddity. The pregnancy chapter prints "Case 21 (continued from page 189)" [read: PDF p.317]: Kilner is continuing an earlier case, not reusing a number. The adjacent case is numbered 89 in the OCR [read: PDF p.315]. I did not trace "Case 88". Drop the item unless someone finds a real duplicate.
2. facts.json says the observer's own visual system "is not on his list" of causes of a changed C.C. band. That is true of the four listed causes (skin, aura thickness, texture, colour) [read: p.136-137]. But Kilner does write that the "complementary colours are entirely subjective" [read: p.121], that eye movement spoils the afterimage [read: p.115], that eyes fatigue within minutes [read: p.130], and that the Aura looks blue "most likely" because of the screen and its "long period of action upon the retina" [read: p.138]. So he saw the observer-side explanations and set them aside without a control. The accurate statement is "noticed but not controlled", which is a stronger criticism than "not considered".
3. Claim 2 in claims.md says the aura "lies outside the ordinary visible spectrum". In the 1911 book this is hedged ("perhaps, but this is only supposititious... Lavender Grey", p.107-108). The firmer "ultra-violet phenomenon" is the 1920 preface (Investigator, archive.org note). The claim should be stated in both forms; I judge both below.
4. The mainstream-conflict line on uranium ("uranium radiation is ionising and not visible this way") omits a more specific ordinary-physics point: uranyl salts are fluorescent under blue or ultraviolet light. See claim 2. [memory, medium].
5. Confirmed: six experiments, not five, in Case 42; Experiments 5 and 6 test location not colour; the "G.2 = B.G." identification is an inference; all by one observer. I checked the Appendix text against the deep read for Exp. 5 and 6 and the C.C. predictions on PDF p.158-159 and found them accurate.
6. Investigator item to keep but qualify: "dicyanin superseded ... by cheaper substitutes" and "chemist asked to stay anonymous" are from Boddington, who sells Aurospecs (a seller's account). Kept below as such.

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B. Background the reader needs (plain language)

What Kilner did. He looked at a person standing against a dark background in dim, diffuse daylight, after first staring for some seconds at a bright light through a flat glass cell of the blue dye dicyanin in alcohol. He then saw a faint grey-blue haze around the body and called it the aura [read: p.5-8, 24-27, 108-112].

What mainstream vision science says is going on (candidates, not proven for his cases). - Afterimage: staring at a bright, coloured light bleaches (temporarily desensitises) the retinal receptors that responded to it; looking away shows a ghost patch of the opposite colour or brightness. Kilner's own spectroscope check says the screen removes orange and most yellow and leaves red and blue slightly dimmed [read: p.112]. Adapting the eye to that tinted light shifts the colour balance of everything seen for a minute or so (called chromatic adaptation). Kilner himself says the aura always looks blue-grey "most likely due to the employment of the spectauranine screen and ... its long period of action upon the retina" [read: p.138]. That is the mainstream explanation of the colour, in his own words. - Dark adaptation and low-light vision: Kilner says the aura is seen only in dim light [read: p.108-109]. In dim light the eye uses rods (dim-light receptors) with poor spatial detail and no colour. Faint haze, grain and drifting patterns ("visual noise") are normal there. - Edge effects: next to a bright edge the eye produces light and dark bands that are not in the scene (lateral inhibition, the Mach-band effect). Scattered light inside the eye (veiling glare) puts a faint halo round any bright object on a dark ground. The "Etheric Double" is a dark band about 1/8 to 3/16 in wide next to the skin [read: facts.json from p.40-41]. At a viewing distance of 2 m (my assumption, the text gives no distance here) that is about 5 arcminutes of visual angle, the scale of the eye's own blur. The Inner Aura (about 3 in) is about 2 degrees, and the Outer Aura (up to 12 in) about 8 degrees, at 2 m. [Calculation, this review.] - Troxler fading and filling-in: fixed, faint patterns fade and reappear; the brain fills gaps. Kilner reports the aura "vanishes and reappears" in the will experiments (Exp. 1) [read: deep read p.333-334]. - Real air effects: a warm body is surrounded by a rising layer of warm moist air a few millimetres to centimetres thick. Its refractive index differs from the room air by about Δn ≈ n₁·ΔT/T. With n₁ ≈ 2.9×10⁻⁴ (air at room temperature), ΔT ≈ 10 K, T ≈ 300 K, I get Δn ≈ 1×10⁻⁵ [calculation; constants memory, high]. That is invisible to the unaided eye but is imaged routinely by schlieren photography (a method that turns tiny refractive-index gradients into brightness) [memory, high]. De Fontenay raised this kind of "ordinary" aura in 1912 (Investigator, IAPSOP note). It cannot explain a structured, striated Inner Aura with rays, but it is a real physical haze, and it would be disturbed by a hand or a draught (so the "mutual attraction of auras" [read: p.105] has an air-flow analogue).

What a sceptic must also respect. Kilner is not a cheat on the face of the text. He reports failures (the Exp. 3 yellow never became true yellow; the willed red never matched the cue book [read: deep read p.333, 335]; his eyes were hurt by the screens, p.7), warns that "enthusiasm and imagination can mislead" [read: p.10-11 per facts.json], and describes the apparatus and the conditions in enough detail for another person to try. That is why the Paris and Philadelphia re-trials (section D) are informative.

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C. The claims

Claim 1: A structured haze (Etheric Double, Inner and Outer Aura) surrounds every body and becomes visible to ordinary eyes after looking through a dicyanin screen.

a. Mathematics. There is almost none; the claim is observational. The one quantitative paper (the 1911-12 "chromatic focus" paper, Investigator lead 1) is checkable: see "Chromatic-focus check" below. Internally the book is consistent in what it says the screen does, with one tension: the observer is advised to look at the light through a dark screen first and then at the subject "with or without" a light screen, and he admits that sometimes the light screen works better and sometimes the reverse "though the conditions may be exactly similar" [read: p.8].

b. Consistency with experiment. Two parts. - Weak form (observers, after the screen routine and in dim light, see a faint haze or band round a body): consistent with established vision effects listed in section B. Surya's Graz observers report a haze, one seeing it with the naked eye afterwards (Investigator, Feerhow 1913); the Philadelphia letter-writers "H. C. S." and Goodspeed saw "some of the effects" [read, via Investigator: Archives of the Roentgen Ray v.16 pp.199-200]. None of this needs a new kind of radiation. - Strong form (the haze is an objective, body-specific emanation that carries structure and information): no established experiment supports it. The only independent physical-style comparison on record points the other way: H. C. S. found the phenomenon "more pronounced with an inanimate hand-towel than with the human being" [read via Investigator, p.199-200]. Kilner himself says he has never seen haze round an inanimate object "except a magnet or a radio-active substance" (p.240), which conflicts with the H. C. S. towel observation. Both statements are kept.

c. Tests. By Kilner: the whole book, one observer, no counts, no blinding. By others: - In favour (second-hand): O'Donnell at Mercy Hospital, Chicago, 1911, reported in the New York Herald of 15 Jun 1911 to have repeated Kilner's experiments before about 20 physicians (via de Fontenay 1912); an encyclopedia entry says he "controlled and confirmed" them, citing Harry Price. I have not read either primary source, and neither says how success was judged [web, via Investigator]. The unsigned Archives of the Roentgen Ray review says "many of them are able to see a bluish haze" after Kilner's demonstration to medical men [web: HathiTrust uc1.d0010345536 p.156]; the journal is published by the book's own publisher, who also sold the screens (interested party). Surya (Graz) reports about 50% see nothing at first use and two detailed positives, in publications of the publisher of Feerhow's book (interested party, as Feerhow notes) [web, via Investigator]. - Against: de Rochas, de Fontenay and Roux, Paris, 1911-12, saw nothing matching Kilner's descriptions with Kilner's own screens; one clairvoyant subject said the screen helped. De Fontenay calls it "a reservation, not a denial" [web: Annales des Sciences Psychiques 22 (1912) pp.74-84, via Investigator]. The BMJ reviewer, according to Wikipedia, wrote that Kilner "has failed to convince us that his 'aura' is more real than Macbeth's visionary dagger", and Wikipedia adds that BMJ scientists "attempted to replicate" with negative results [web: https://en.wikipedia.org/wiki/Walter_John_Kilner]. I could not open the review (the PMC pages gave an HTML challenge instead of the PDF). The replication sentence stays unverified, and so does whether the BMJ ran a trial at all. - No trial found uses the minimum design: unknown subject versus empty (or decoy) background, observer blind, several observers, recorded hits and misses. Nobody tested whether the same haze appears round a warm towel, a mannequin or a dummy at body temperature.

d. What would have to change if true. If the strong form were true, the body would need to emit a field or radiation that (i) is not infrared or ordinary light, (ii) is invisible to normal eyes yet becomes visible after a bright-light adaptation, and (iii) is not recorded by photographic plates. Photography failed in the book (p.9-10 per facts.json; the 1920 preface says "to a slight extent"). Physics would need a new interaction between living tissue and light that leaves no trace in any detector. If only the weak form is true, nothing changes in physics; a chapter of visual psychophysics gains a worked example.

Chromatic-focus check (Investigator lead 1, Kilner's own quantitative work). Kilner reports observers refocusing a microscope by +1 to +6.5 divisions (one division = 1/1000 in = 25.4 µm of stage travel) after viewing light through dicyanin [web: HathiTrust uc1.d0010345536 p.344-352, via Investigator]. I did not see the paper's raw table. Two checks I can do: - Depth of focus: a 1/4-in objective has a numerical aperture (NA, light-gathering angle) of perhaps 0.25 [assumption]. Depth of field from diffraction alone is about λ/NA² = 0.55 µm / 0.0625 ≈ 9 µm, a third of one division. So a shift of 1-2 divisions is only 3-6 depths of field, and the person's setting can easily drift by that much between sessions. - What the eye would have to do: stage travel Δz moves the image by M²Δz, where M is the objective magnification (the longitudinal magnification of a microscope is M²). The eyepiece of focal length f then changes the light's vergence (reciprocal distance, in dioptres, D) by M²Δz/f². For M = 10, f = 25 mm: 4 D per division. For M = 25, f = 50 mm: 6 D per division [calculation; M and f are my assumptions, not in the source as I read it]. A change of the eye's focus by 2.5 divisions would then mean 10 D or more, which is far beyond the eye's known chromatic difference of about 2 D across the whole visible spectrum [memory, high]. The result therefore cannot be a pure chromatic effect of the eye. More likely the observer's accommodation (the lens's focusing) or the setting criterion changed, which Kilner says he excluded by refocusing "repeatedly with the coarse adjustment" [web, via Investigator]. This is a weak check because the key parameters are assumed, and I mark it as a lead for the Mathematician: it shows the method is a very sensitive amplifier of small accommodation differences, so it cannot by itself prove a shift toward violet.

Verdict, split. - Weak form (observers report a faint haze or edge band after screen adaptation): Plausible, untested as a perceptual fact. It is consistent with known visual effects, which are the likely cause; the screen routine has not been compared with a sham screen. - Strong form (an objective, body-specific, structured emanation seen through dicyanin): Never properly tested. Not dismissed without testing (Paris, Philadelphia, Chicago and perhaps the BMJ tried), but none of those trials was blinded or counted, and the one inanimate-object comparison on record (H. C. S.) leans against human specificity.

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Claim 2: The aura is a force from the body acting on the ether (1 aF and 2 aF), lies outside the visible spectrum, and has counterparts in hazes round magnets, radio-active uranium and galvanic circuits.

a. Mathematics. No equations. Internally, the argument runs: if a substance emits vibrations that match the visible spectrum, it is "auto-luminous"; Reichenbach's "sensitives" saw light from magnets; since ordinary keen-sighted people have not noticed this, the vibrations "lie just outside the Solar Spectrum"; so people who see the aura have "a faculty to see rays that are not included in the ordinarily visible Spectrum" [read: p.106-108]. This is internally tense: the vibration is defined as not visible, yet it is said to be seen, through a screen that, by Kilner's own spectroscope, only removes orange and yellow from ordinary visible light [read: p.112]. A screen that absorbs part of the visible spectrum cannot make a non-visible radiation visible; at most it can change how the eye adapts. Kilner recognises the gap: the eye's change is the "all-important factor" [read: p.109], and the explanation is "completely hypothetical and without proof" [read: p.112]. He also supposes the force produces vibrations in the ether and not light, yet calls the haze "bluish" or "yellowish" like the colours of light [read: p.96-98]. The two-force argument (a rayed, striated Inner Aura versus a nebulous Outer Aura that grows in females at puberty, p.100-101) is an argument from appearance, not from a measured quantity.

b. Consistency with experiment. - Ether: the luminiferous ether (a supposed medium carrying light) was given up after Michelson-Morley (1887) and Einstein (1905) [memory, high]. A "force acting on the ether" has no content in modern physics. - Beyond the visible spectrum: the human eye is limited to about 380-740 nm; the cornea and lens absorb most ultraviolet below about 380 nm [memory, high], and the glass and alcohol cell used would also pass little of it. The 1920 "ultra-violet" version [read: Investigator, archive.org note] is testable: ultraviolet exposes ordinary photographic plates and is detected by quartz optics and UV fluorescence. Kilner's own attempts to photograph the aura (panchromatic, ultrared, ultraviolet plates) failed [read: facts.json from p.109-123]; the 1920 preface admits "slight" success only. That is a null result from the inventor himself. - Magnet haze: a static magnetic field does not emit light and does not interact with light in air at ordinary strengths [memory, high]. No physical mechanism is offered in the book. Kilner says the haze did not follow the field lines [read: p.94]. His own conditions (smooth black ground, diffuse light, double the usual screen-staring time, p.94) are those that produce visual haze round any bright, small object, and he reports the haze is brighter at points and between nearby objects (p.96, 98), which is also what scattered light inside the eye does. - Uranium nitrate: uranyl compounds really do fluoresce (give out green-yellow light) when excited by violet or ultraviolet light [memory, medium; not web-checked: I did one search on dicyanin spectra, which found nothing specific and none on uranyl]. Daylight contains some. A yellow haze that is "more clearly seen through a light yellow screen" and "lessened or obliterated" by a blue one [read: p.97] fits fluorescence or ordinary yellow-tinted crystals better than radioactivity: ionising radiation at that activity is far too weak to be seen as a visible cloud [memory, high]. No one has to accept that as proven; the crystal could be re-examined with a control crystal of a non-radioactive uranyl or yellow salt. - Galvanic cell: Kilner says most people cannot see a haze round disconnected cell poles, but it "will become visible" with the procedure [read: p.97-98]. A bare wire pair 2 in apart looking "nebulous" in the gap is typical of veiling glare between two bright-edged objects. - N-rays: Kilner's earlier work used needle deflections he ascribed to "N rays" and explained their erratic results as rays falling or not falling on the needle [read: p.101-102]. N-rays were claimed by Blondlot in 1903; R. W. Wood showed in 1904 by secretly removing an essential prism and swapping the "emitting" file for a piece of wood that observers still "saw" the effects [web: https://en.wikipedia.org/wiki/N_ray]. N-ray results are a documented case of experimenters seeing what their expectation told them, using faint, threshold-level sensations. Nickell (1993, via Wikipedia) makes the same link to Kilner; that is a sceptic's characterisation. The link matters: the same mechanism (expectation at the edge of detection) is the leading candidate for Kilner's rays and for the Appendix results. - Wimshurst experiments (1920 edition, 1915): auras vanished on charging a patient on an insulated stool, then returned 3 in wider [read: Investigator, archive.org note]. A person charged to tens of kilovolts will also shed ions and move air; a visual halo that changes could track that. Single-observer, unblinded.

c. Tests. Photography attempts by Kilner (negative). H. C. S./Goodspeed: effect stronger on a towel (so not specific to a living body). The NYT headline of 5 Feb 1911 ("The human aura has at last been photographed", article text not read; Investigator, partial) conflicts with the book's own report of failure; its content is unknown. Feerhow and the 1912 Annales review of Werner and Caan report weak "photo-activity" of human tissue on photographic plates (Investigator, priority 3). I have not read these; they are a different effect (fogging of plates by contact) from visible haze and are not evidence for it. No test of the magnet, uranium or galvanic hazes by anyone other than Kilner has been found.

d. What would have to change. An ether-mediated bodily force: the whole post-1905 picture of light and fields would have to be reopened. A visible haze round a static magnet or an inert galvanic wire: the interaction of static fields with air or light. A radiation in the ultraviolet from a living body at room temperature: a body emits thermal infrared (peak near 9-10 µm at 310 K) and a very faint ultraviolet/visible "biophoton" emission of order a few photons per second per cm², some 10⁻¹² of room light [memory, medium]. That is not a haze anyone could see. Nothing in mainstream physics has to change for the ordinary-vision reading.

Verdict, split. - The ether-force and "two auric forces": Historically superseded but instructive (a reasonable 1911 reading of Reichenbach and N-ray ideas, replaced by field theory and relativity). - Outside-the-visible-spectrum/ultraviolet: Tested, not supported by Kilner's own failed photography, and Internally inconsistent as stated in 1911 (the same vibration is "not visible" and "seen through a visible-light filter"). - Hazes round magnets, uranium and galvanic wires: Never properly tested (one observer, no control objects; no mechanism offered; ordinary visual and fluorescence explanations not excluded).

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Claim 3: Aura size, shape, texture and colour reflect sex, age, heredity, temperament and disease (hysteria, epilepsy, hemiplegia, local disease, pregnancy).

a. Mathematics. Width numbers are tabulated in about 40 cases (infants to age 58) [read: facts.json from p.34-78]. There is no averaging, spread, or comparison with chance. Statistics offered are descriptive ("typically ... wide trunk, lumbar bulge in hysteria"). One example of the logic: the epileptic whose aura was judged epileptic "A few days later this was confirmed as she had a fit" [read: p.186 per the grep: case text near "Haut and Petit Mal"] is an anecdote with a stated outcome, one of the few I found where a prediction and a result are both given. I found no case list with a full set of predictions and outcomes.

b. Consistency with experiment. Nothing in physics forbids a body's appearance varying with age and sex; the question is whether the measured quantity (width of a haze) is a property of the body. If the haze is largely a visual construct then its width depends on the observer's adaptation, lighting and background as much as on the subject. Kilner controls some of these (background, diffuse one-sided light, distance 1-2 in margins [read: p.8, 105]) but does not test the same subject on different days with a different observer.

c. Tests. Only Kilner. The unsigned Archives of the Roentgen Ray review declines to assess the disease claims ("if succeeding investigators should confirm his results ..." [web, via Investigator]). No replication or blind classification of cases found.

d. What would change. If sex, age and temperament were encoded in an emanation from the body, there would be a physical carrier of constitutional information with no known counterpart; unlikely. If the shapes reflect gross anatomy (a wider female hip and trunk, posture in hysteria, a hemiplegic's stance), they need no new physics: the "aura" would be tracking body outline and warmth.

Verdict. Never properly tested (a testable claim; no blinded classification, no inter-observer agreement; dismissed in practice without testing by the mainstream, which did try the screens in 1911-12 but not this claim).

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Claim 4: A complementary-colour (C.C.) band cast on a patient turns lighter or darker over local disease, tenderness, impending menstruation, early pregnancy or a dead foetus, so it can be used for diagnosis.

Plain-language setup. The observer stares at a strip of coloured paper for 30-60 s, then looks at the patient. He sees a ghost strip in the opposite colour (a negative afterimage) lying across and beyond the body. Kilner judges whether the ghost looks lighter or darker over particular patches.

a. Mathematics. None. The logic is by elimination: four causes (skin, thickness, texture, colour of the aura) [read: p.136-137].

b. Consistency with experiment. The afterimage is real and its apparent brightness depends on the brightness and colour of the surface it is projected on (this is standard; the afterimage appears to add or subtract from the light coming off the surface) [memory, high]. Skin that is flushed, pale, shiny with sweat, shaded by body curvature or lit at a different angle will carry a lighter or darker ghost. Inflamed or congested skin (disease, tenderness, early menstruation, breast changes) differs in reflectance, so a skin-surface signal is plausible, and it would carry a little real, if crude, physiological information. This is the mainstream-compatible reading, and it is what Kilner's cause (1) "skin" would catch. He recognises that skin and lighting vary and tries to exclude them by turning the patient round (Exp. 1 turn-round, p.334-335) and by a black or white background. The residual causes (eye movement, fatigue, individual retina, expectation) are named by him but not controlled [section A, item 2]. The "colour of the aura" step is his last resort for "all the remaining cases" [read: p.137]; it is a hypothesis for unexplained residue, not a result.

c. Tests. Kilner's case notes with outcomes (for example: a lady "believed herself pregnant": no discoloration over the pubes, prediction "pregnancy out of the question ... menstruation would not take place within four or five days", it came "just seven days after" [read: PDF p.317]; a young woman expected to menstruate "in three or four days", no change above the pubes, "her period was a week later than the right date"). Note the pattern: the pregnancy sign is largely the absence of a darker patch, which is the more probable finding, and the timing predictions were off by days in two of the two outcomes I saw reported. A selective set of illustrative cases with no denominator (how many were wrong?) cannot give a sensitivity or specificity. No second observer, no blinding, no comparison with a physician's independent diagnosis. I did not read the dead-foetus and cancer sections in detail.

d. What would change. Nothing, for the skin-reflectance reading. For an "aura-colour" reading: a living body would need a colour-coded emanation visible to the afterimage-adapted eye and not to the naked eye; see claim 5.

Verdict. Never properly tested as a diagnostic method. The kernel (afterimage patches track skin and lighting differences) is Plausible, untested as a crude sign; the specific obstetric claims (early pregnancy, dead foetus) have no test and no support beyond Kilner's reported cases.

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Claim 5: The C.C. band changes, in cases texture does not explain, come from the aura's colour, which the naked eye cannot see.

a. Mathematics. The logic is an elimination argument: three causes fail to explain some cases; therefore the fourth must be at work (p.136-137). Hidden assumptions: the list is exhaustive (it omits the observer's visual system, illumination geometry and body curvature, and expectation); and a colour too faint to see directly is strong enough to modulate an afterimage, which Kilner supports by "presumptive evidence": "clairvoyants affirm that they can see the Auras in all colours" [read: p.137]. That is a circular citation: it takes the claimed faculty as proof of the aura's colour.

b. Consistency with experiment. Is it possible for a colour below the visibility threshold to show in the afterimage? Adaptation changes sensitivity, so contrast near threshold can be altered, but that would amplify noise and drift as well as signal, and I know of no measurement showing it makes a subthreshold coloured veil detectable [memory, medium]. No physical detector of the aura's colour exists.

c. Tests. Kilner's footnote makes the Appendix experiments his evidence for this claim [read: p.137, footnote 1; deep read]. Those experiments do not test it; see claim 6.

d. What would change. Nothing (if false); a new coloured emanation (if true).

Verdict. Never properly tested. As an inference it rests on elimination and on a premise (the clairvoyants) that is the claim under test.

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Claim 6: The will can project rays from the Inner Aura and change the aura's colour; in two trials with an unknown spot the observer located the willed spot with the blue C.C. band (one at the exact centre, one 0.5 in off), using one subject who could see auras herself.

What was done. Read myself in the deep read and checked against PDF p.157-158 (Kilner's own prediction that a red or yellow ray seen end-on is invisible to the naked eye and appears dark on a blue band) [read: p.138-139]. Subject D., a paid artist's model, 28, hysterical temperament, "able to see the Aura easily ... sometimes even before the observer could" [read: deep read p.331-333]. Exp. 5: she wills a red spot "somewhere upon the abdomen"; the observer examines with the blue band and "almost immediately" finds a darker spot above and left of the navel; the finger placed on it is "the exact centre". Exp. 6: yellow spot, unknown place on the thorax; a dark patch about 2 in across on the upper left breast; finger half an inch from the true centre. She was fatigued; "No more experiments of this nature were possible" [read: p.337-338].

a. Mathematics. No calculation is given. A rough chance estimate (my own, with assumptions): treat the abdomen as about 30 × 25 cm and "hit" as within 2.5 cm of the true centre; a single random guess lands in the target with probability about π(2.54)²/750 ≈ 3%. For the thorax, similar, a few percent. Two such hits would be unlikely by luck if the observer picked one location at random and if the subject gave no cue. Neither condition holds: (i) the C.C. band shows many dark patches on a body (Kilner says a sacral patch is common, p.295), so the observer searched a patterned field and chose one that looked right; a posteriori selection of a single "dark patch" is not a random guess; (ii) the subject told him "when to look" and "could inform us" [read: p.337]; she could see the aura, she was in view, and she was facing him. Eye and head direction, shifts of posture, or breath-holding can mark a location to within an inch or two; ordinary ideomotor-type cues are not excluded. No other number (misses, rejected patches, number of trials not reported) is given, so no p-value can honestly be computed. The text uses one hit and one near-miss (with "diffuseness" explained afterwards by fatigue, p.338): the near-miss is reported as a hit.

b. Consistency with experiment. Compatible with: a cue-assisted search by an expecting observer (the pattern of N-ray work). Not independent evidence for a physical colour change: only the blue band was used in the blind trials, and by Kilner's own prediction both red and yellow rays darken the blue band [read: p.138-139; deep read §6]. So the trials test location, not colour, as the Step 1 notes say. The colour-specific pattern (dark on blue and yellow, light on red) is reported only in Exp. 1 and 4, where observer knew colour and site. No sham ("will nothing") trial. The willed rays in Case 41 were chosen by the observer, the subject knew the site, and the observer judged by eye after he had demonstrated the effect to her (p.327): a demand-characteristic setup.

c. Tests. One observer, two blind-location trials, one subject who sees auras. The 1920 edition adds experiments (women who "change the colour of their auras at will") not read in depth. No replication or independent observer found.

d. What would change. If volition produced a coloured emanation in living tissue that can be located by another person's afterimage, physics would need a pathway from a neural state to an optical signal: a direct mind-matter coupling. The simplest alternative needs no change: cues plus expectation.

Verdict, split. - Willed rays and willed colour changes as an objective phenomenon: Never properly tested (no blinding of the cue channel, no control trials, an observer who held the hypothesis). - Location trials as evidence for colour specificity of the C.C. band: Not testable as stated in that form, since both predicted colours give the same signal on the blue band; they could support only "the subject could mark a place".

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D. Investigator's findings and how I weigh them (kept in full)

Records still needed, in order of value for my verdicts: (1) the BMJ 1912 review text; (2) the Herald/Chicago reports and any hospital record on O'Donnell; (3) the NYT 1911 article; (4) Kilner's chromatic-focus table; (5) the Rebman 1912 booklet.

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E. Summary table

What would settle most of this in one stroke: a double-blind comparison, several observers, a screen routine versus a sham filter, subjects behind a screen that blocks view of each other (so no cueing), mixed with warm decoy objects and empty positions, with hits and misses counted in advance of the trial. Nothing close to this is on record.