The illustrated optical manual, or Handbook of instructions for the guidance of surgeons in testing quality and range of vision, and in distinguishing and dealing with optical defects in general / by Surgeon-General Sir T. Longmore.

Thomas Longmore

Date:: 1888

Credit: The illustrated optical manual, or Handbook of instructions for the guidance of surgeons in testing quality and range of vision, and in distinguishing and dealing with optical defects in general / by Surgeon-General Sir T. Longmore. 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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$Brightness of objects at different dis- tances, 15 Bull's-eyes and centres of targets, 182 of targets, sizes of, 183 Causes of asthenopia 173 ■— of bypermetropia, 71 — of presbyopia, 131 -— optical, of erametropia, 59 of myopia, 61 Central acutencss of vision, 155 Chromatic aberration, 27 Circles of diffusion, 62 Circular test-dots, 180 — W.O. of September 1887, 225 Colour-blindness, 144 amblyopic, 153 causes of, 146 ■ congenital, 145 diagnosis of, 147 • disqualifying effect of, 151 Holmgren's test of, 14S lantern test of, 150 and military service, 151 and naval service, 152 symptoms of, 145 varieties of, 145 Colour-sense, acuteness of, 147 defects of, 145 Coloured vision, 153 Composition of lenses, 37 Concave lenses, 19 — lens, power of, 35 Concomitant strabismus, 139 Continental armies, ametropia in, 207 Convergence and accommodation, 129 Convergent strabismus, 137 Convex lenses, 19 — lens, power of, 35 Correction of astigmatism, 98 ■— of myopia, 68 Counterfeit myopia, 69 Counting test-dots, ISO Cylinder, principal features of, 29 Cylindrical lenses, 28 bi-concave, 28 bi-convex, 28 plano-concave, 29 — — plano-convex, 29 simple, 28 sphero-concave, 30 — sphero-convex, 30 tests of, 34 varieties of, 28 — lens, action of, on light, 30 power of, 36 Definition of amblyopia, 16 ol' arhroinotopsirt, 1 I I — of accommodatory power of the eye, 122 Definition of asthenopia, 173 — of as — of ' circles of diffusion,' 62 — of colour-blindness, 14 4 — of emmetropia, 59 — of ' Held of vision,' 11 ■— of 'finite rays,' 18 — of hemeralopia, 169 — of hemiopia, 1 71 — of hypermetropia, 73 — of ' infinite rays,1 1 7 — of ' infinity,' 17 — of lenses. 1 '.i — of myopia, 60 — of nyctalopia, 170 — of oversightedness, 7:! — of ' pencil of rays,' 6 — of perfect vision, 2 — of presbyopia, 130 — of prisms, 31 — of ' radiation,' 6 — of ' ray of light,' 6 — of scotoma, 172 — of shortsightedness, 60 — of strabismus, 137 — of ' visual angle,' 10 Degree of hypermetropia, 80 — of myopia, 67 Diagnosis of asthenopia, 174 — of astigmatism. 90 ophthalmoscopic, 111 — of colour-blindness, 147 — of defects of vision, 190 — of emmetropia, 59 — of hypermetropia, 7S ophthalmoscopic, 110 — by keratoscopy, 120 — of myopia, 65 ophthalmoscopic, 110 — of oversightedness, 78 ■— of presbyopia, 133 — of sh rrtsightedness, 65 Diffusion, circli s of, 62 ■— images in astigmatism, 88 Dimsightedness, 177 Diplopia, 5 — images homonymous, 4 — images crossed, 5 — and strabismus, L39 Disqualifying visual effects, 199 Distance, art of judging, 50 Divergent si rabisinus, 137 I louble concave Ui>es, 19 — convex lenses, !'.' — vision. 5 I tuples-focal «] ectacles, l> I >\ schromotopsia, M1 Em uetropia, 59 - definition of, 59$