The economy of the eyes : precepts for the improvement and preservation of the sight. Plain rules which will enable all to judge exactly when, and what spectacles are best calculated for their eyes. Observations on opera glasses and theatres, and an account of the pancratic magnifier, for double stars, and day telescopes / By William Kitchiner.

  • Kitchiner, William, 1775?-1827.
Date:
1824
Catalogue details

Licence: Public Domain Mark

Credit: The economy of the eyes : precepts for the improvement and preservation of the sight. Plain rules which will enable all to judge exactly when, and what spectacles are best calculated for their eyes. Observations on opera glasses and theatres, and an account of the pancratic magnifier, for double stars, and day telescopes / By William Kitchiner. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    became so grievous, that at two or three-arid- thirty, I determined to try a concave glass: and then found that the numbers 2 and 3 were to me in the relation so well described by Mr. Ware ; that is, I could see distant objects tolerably well with the former number, but still more accurately with the latter. After contenting myself a little time with No. 2, I laid it wholly aside for No. 3, and, in the course of a few more years, came to No. 5, at which point my eye has now been stationary between fifteen and twenty years. An earlier use of concave glasses would probably have made me more Near-sighted, or would have brought on my present degree of myopy at an earlier period of life. If my friends had per- suaded me to read and write with the book or paper always as far from my eye as I could see; or if I had occasionally intermitted study, and taken to field sports, or any employment which would have obliged me to look much at distant objects, it is very probable that I might not have been Near-sighted at all. Possibly the persons who become Near-sighted, by having constantly to adjust their eyes to near objects, may not usually change to be Long- sighted by Age. p. 111.