A critical inquiry respecting a new membrane in the eye : discovered by Mr. George Hunsley Fielding, and described by him in a lecture delivered at Oxford, before the late meeting of the British Association for the Advancement of Science / by William Gordon.

  • Gordon, William, 1800-1849.
Date:
1832
Catalogue details

Licence: Public Domain Mark

Credit: A critical inquiry respecting a new membrane in the eye : discovered by Mr. George Hunsley Fielding, and described by him in a lecture delivered at Oxford, before the late meeting of the British Association for the Advancement of Science / by William Gordon. 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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    knows whether it be furnished with nerves at all. To imag ine, that because it is membranous, it must besensitiveeven withoutnerves, partakes too much of theStahlian doctrine for the physiologists of the present day. With regard to the undulations of theMembrana Versicolor, I may remark, that Mr. Fielding has no means of ascertaining whether such undulations ever take place ; and as to his Hartleian* Hypothesis, that the undulations of the Retina are propagated in a series of vibrations along the Optick Nerve to the Sensorium, it is perfectly gratuitous; in short, the experiments of Dr. Wilson Philip have shown that the nerves, even Avhen divided, can convey impressions to the Brain—a circiunstance which entirely dis- proves that nervous action consists in any vibra- tory or oscillatory motion.-]- From facts, then, as Avell as from the most legitimate arguments, it appears, that the theory of undulation is founded on data and reasoning not more satisfactory than those, on which is based the theory of reflection. It is not easy to determine which of Mr. Field- ing's theories is the most charged with difficul- ties. If we adopt the theory of undulation, we must not only dispense with the new membrane (the Membrana Versicolor), or at least (supposing * Vitl. Harllcy on Man. t Vid, Philip'ri Experim. Inquiry. G
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