The human sensorium : investigated as to figure by a course of pressures on the eyes, and by the induced phases and bearings of those sensations of colors called peacock's feathers : being a second supplement to the Rationale of cerebral vision / by John Fearn.

  • Fearn, John, 1768-1837.
Date:
[1832]
Catalogue details

Licence: Public Domain Mark

Credit: The human sensorium : investigated as to figure by a course of pressures on the eyes, and by the induced phases and bearings of those sensations of colors called peacock's feathers : being a second supplement to the Rationale of cerebral vision / 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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    PREFACE. That Visual Modification of the Mind—in other words that Circular Mass of Sensations of Color—which has by Sir Isaac Newton been likened to the feather in a peacock's tail, is a phenomenon which opens to us a road to the investigation of the nature of the Sentient Subject that never could have been afi*orded by vision from Light, since it is impossible that light, reflected from ex- ternal objects, can be made to fall upon the eye so as to impress the retina upon many of those points, which it is necessary to impress in order to induce visual phenomena in the situations, bearings, and mutations, which alone can indicate, in any extent however small, the Physiolo- gical Condition or Figure of the Sentient, the investiga- tion of which, as far as may be done from certain data, is the purpose of the present supplement. At the same time, it claims remark here, as an im- portant example of oversight, to what an extent this spe- cies of vision has been neglected ; while its existence is so obvious, and even so obtrusive upon the notice of all men, that scarcely any human being can be altogether ignorant of the fact. The case of Sir Isaac Newton; and that of Dr. Porterfield, who wrote so largely on Vision, and who held as strongly for the existence of a Sensorium, against the denial of it set up by Dr. Reid, as Newton himself would have done had he been in life; would have ap- peared to me almost impossible, were it not that an equal extent of neglect has happened in my own case, during twenty years after I had actually experimented a course of general pressures on the eyes, with a view to determine the physiology of our visual sensations; at which time, I was perfectly aware of the existence singly taken, though I never thought of seeking for the jtlurality or multiph- cation, of the peacock's feather. Some good may be derived from the fact, now adverted