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
Catalogue details

Licence: Public Domain Mark

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.

    23/296
    CHAPTER III. OBJECTIVE ASSESSMENT OF OCULAR REFRACTION. Subjective and objective modes of visual examination . . .104 Objective assessment of refraction 105 Two rnetbods commonly employed 105 1. Direct Method of Ophthalmoscopic Diagnosis. Conditions wbicb concern tbe eye observed . . . . .106 Direction of rays emitted by an Emc. eve 106 By a Mc.'eye .... 106 By a He. eye .... 107 Conditions which concern tbe ob- server ..... 107 Effect of rays from Emc. eye on observer . . . . .107 Of rays from ZSIc. eye . . . 108 Of rays from He. eye . . . 109 Application of observations to dia- gnosis . . . . . 109 Erect and inverted images . . 109 Objective diagnosis of Em. . , 110 Of M 110 OfH 110 OfAst Measure of ametropia by refraction ophthalmoscopes Description of refraction opbtbal- moscopes .... Manner of employing tbem . Observation of Emc. eye Diagnosis of degree of M. Of degree of H. . Remarks on tbe use of refraction opbtbalmoscopes 2. Keratoscopy. Keratoscopy in military practice Arrangements necessary Appearances in keratoscopy. Nature of keratoscopy. Keratoscopy with concave mirror Estimating ametropia by it . Application in practice Diagnosis of degree of M. or H. General estimate of M. by kerato- scopy .... Measure and correction cf Ast by it ... . Keratoscopy witb plane mirror CHAPTER IV. .ACCOMMODATORY FUNCTION OF THE EYE. A ccommodatiun. Act of Ace..... Demand for Ace.. . Mechanism of Ace. Power cf Ace. Expression of amount of Ace. Measure of amount of Ace. . Region of Ace. Association of Ace. and converg- ence .... Definition Presbyopia. PAGE 111 111 111 112 114 114 114 115 116 116 117 118 118 119 120 120 120 121 121 Optical conditions . 131 . 123 Causes .... 131 . 123 Diminution of Ace. witb age l:J2 . 124 Symptoms .... ]3S . 126 Diagnosis .... 133 . 126 Determination of degree of Pr. 134 . 126 Examples .... 134 . 128 Correction of Pr. . 134 Range of A cc. in Pr. vision . 134 129 Pr. witb M. ... 136 Pr. witb H 135 130 CHAPTER V. ON IMPAIRED VISION CONNECTED WITH STRABISMUS. Strabismus. Directions of deviation in strabis- Defiuition . Various forms of strabismus . 137 mus. , 1^7 Apparent strabismus . 137 138