Volume 2

Medical portrait gallery : Biographical memoirs of the most celebrated physicians, surgeons, etc., etc., who have contributed to the advancement of medical science. / By Thomas Joseph Pettigrew.

  • Pettigrew, Thomas Joseph, 1791-1865.
Date:
1839
Catalogue details

Licence: Public Domain Mark

Credit: Medical portrait gallery : Biographical memoirs of the most celebrated physicians, surgeons, etc., etc., who have contributed to the advancement of medical science. / By Thomas Joseph Pettigrew. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    even calls it the crystalline muscle; but he does not hint at the office of it, as explained by Young. Mr. E. Home in a paper read ' in the same year as that of Dr. Young, communicating some facts relative to Mr. John Hunter's preparation for the Croonian Lecture of that year, which, unfortunately for science he did not survive to deliver, claims for him the suggestion of the use of the lens and its power in regulating its own internal actions to adjust itself so as to adapt the eye to view ob- jects at different distances. It appears that Mr. Hunter had remarked the fibrous structure in the lens of the cuttle-fish. 2. (1800, p. 106.) Outlines of Experiments and Inquiries respecting Sound and Light. These are arranged under sixteen different heads, and are offered only as the first steps of an investigation. In the fifteenth division a technical description is given of the formation of sounds by the configu- ration and inflexions of the vocal organ. The author intimates, that by a close attention to the harmonies entering into the constitution of various sounds, much more may be done in their analysis than could otherwise be expected. 3. (1801, p. 23.) On the Mechanism of the Eye. This is a Bakerian Lecture. It contains a variety of ingenious observations of a general nature pertaining to vision, treats particularly of the focal distances of the eye, and suggests an improved optometer. It also enters upon a minute con- sideration of the dimensions and refractive powers of the human eye in its quiescent state, and the form and magnitude of the picture which is deline- ated on the retina. The power of the lens in altering the focal length of the eye is further considered, and it is shown that in persons who have had the lens removed in the operation of Extraction of the Cataract, the actual focal distance is totally unchangeable. 4. (1802, p. 12.) On the Theory of Light and Colours. Another Bakerian Lecture. This paper developed the important law of Interference established by Dr. Young, which M, Arago regards as his chief discovery, and one that will render his name imperishable. Dr. Young in this paper says he thinks himself authorized to assert, without hesitation, that radiant light consits in undulations of the luminiferous aether. The increase or diminution of light, he thinks clearly referable to an increase or diminution of the undulations, and that all the affections to which the undulations would be liable, are distinctly visible in the phenomenon of light, and that it may therefore be very logically inferred that the undulations are light. .5. (1802, p. 387.) An Account of sonip Cases nf the Production of