Color images in the brain : being an account of the detection of visible objects, seen posited on exchanged sides in the brain, after the intromission of impressions of light, reflected from external objects, one in each eye ... / by John Fearn.

  • Fearn, John, 1768-1837.
Date:
[1831]
Catalogue details

Licence: Public Domain Mark

Credit: Color images in the brain : being an account of the detection of visible objects, seen posited on exchanged sides in the brain, after the intromission of impressions of light, reflected from external objects, one in each eye ... / by John Fearn. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    ton again illumined the world, and T could command him to FEIGN a set of cases in order to confirm Recrossed Ce- rebral Vision, I could not choose any case more com- pletely in juxtaposition with the whole Rationale and phenomena laid out in my several publications on the sub- ject : For, when we press (for example) simultaneously on the left side of each Eije, we liave Two Peacock's Fea- thers on the right side of the Sensorium, onh of them being more to the right than the other. Can any force of bias resist this fact, when it is taken in combination with Dr. WoUaston's case of Half-field Vision'^—The fact of its happening on DIFFERENT SIDES of the field op VISION at two dijferent times, renders it an experi- mentum crucis of a very rare value and occurrence. Two remarks, of material importance, had not room for insertion in the body of the Letter. First.—All Novices, (as happened to Sir Isaac Newton, as well as to myself,) have thought with Sir David Brewster that the Peacock's Feather is in the opposite margin of the SAME ei/e that is pressed. Nor, perhaps, would the cheat be discovered so long as we employed but one eye. It is onlg upon hanging both eyes into action that the grand secret of the recrossing is revealed, in all its manifest certainty and consequences. Secondly. — The Advocates of External Direction may, still, think it something that the Peacock's Feather is always true to the opposite point of the eye to the point impressed : and they may, perhaps, demand a REA- SON for this. But the wonder must cease when I point out that, the reason is because the eye and the Sen- SORIUM are, each of them. Spherical; so that a Pressure (for example) on the extreme left of the left e occasions a Yekther on the extreme right of the SensoriuM; ivhich must he, since the TWO SPHERES are two co-operating organs, the Pres- sures on the eye being registered, as Color Images, no where hut in the Sensorium.