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Class "T ( E ^^ 
 
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 CORfRIGHT DEPOSm 
 
HYGIENE OF THE EYE 
 
 BY 
 
 WM. CAMPBELL POSEY, A.B., M.D. 
 
 OPHTHALMIC SURGEON TO THE WILLS AND HOWARD HOSPITALS; PROFESSOR OF DISEASES 
 
 OF THE EYE IN THE PHILADELPHIA POLYCLINIC) OPHTHALMOLOGIST TO THE 
 
 DEPARTMENT OF PHYSICAL EDUCATION OF THE UNIVERSITY OF 
 
 PENNSYLVANIA) CHAIRMAN OF THE COMMISSION ON 
 
 CONSERVATION OF VISION OF PENNSYLVANIA 
 
 120 ILLUSTRATIONS 
 
 PHILADELPHIA AND LONDON 
 J. B. LIPPINCOTT COMPANY 
 
^^ 
 
 
 COPTKIGHT, 1918, BY J. B. LIPPINCOTT COMPANY 
 
 Elecirotyped and Printed by J. B. Lippincott Company 
 The Washington Square Press, Philadelphia, U. S. A. 
 
 OCT -8 1918 
 ©CI. A 5(1(5 '17 4 
 
PREFACE 
 
 Sight is the most valuable of all the special senses and 
 the author has endeavored to convey in the following pages, 
 in language as free from technicalities as possible, how it 
 may best be conserved, and the relation which the organ 
 of vision bears to the general economy. Although general 
 practitioners are doubtless more or less familiar with the 
 substance of its contents, it is thought that a review of the 
 more common diseases of the eye, with a description of the 
 manner in which the eye is affected by the general health, 
 and also how the latter may be influenced by eye-strain, 
 will not be without value, both to the physician engaged in 
 general practice and the general public. 
 
 Vision plays such an important part in education that 
 the chapters dealing with the refraction of the eye, the 
 illumination and equipment of the school-room, and the 
 general care of the eyes of the scholar should invite the 
 interest of teachers and parents. 
 
 Blindness and the diseases and conditions leading to 
 it are fully discussed in its pages, together with the national 
 movements which are being made towards its prevention; 
 all of which the author hopes may lessen the labors of those 
 who are so unselfishly leading the movement to diminish 
 the number of blind in this country. 
 
 In view of the increasing number of ocular injuries 
 received by workmen in foundries, factories and elsewhere, 
 particular attention is given to this important subject, as 
 well as to the best means of preventing them — information 
 which should be of value to those engaged with the problem 
 of lessening the number of industrial accidents. 
 
iv PREFACE 
 
 It is hoped by the author that the contents of the four 
 chapters written by distinguished speciaHsts in the subjects 
 which they discuss may prove of interest to ophthalmolo- 
 gists as well as to general practitioners and laymen, as 
 they contain information which should be of value to the 
 specialist hitherto not available in condensed and popular 
 form. Otherwise the author fears his professional col- 
 leagues will find the work elementary and falling far short 
 of what a comprehensive treatise on ocular hygiene treated 
 fully from a scientific standpoint should be. He bespeaks 
 their co-operation, however, in his attempt to convey to the 
 popular reader a broader comprehension of the various 
 phases presented by ocular anomalies and diseases. 
 
 In conclusion, the author desires to express his obliga- 
 tion to the National Committee for the Prevention of Blind- 
 ness, for the loan of a number of photographs, notably 
 those illustrating the chapter on wounds and injuries. 
 
 The Author 
 
 2049 Chestnut Street, 
 
 Philadelphia, Pa. 
 
 June 1, 1918 
 
CONTENTS 
 
 CHAPTER PAGE 
 
 I. Structure of the Eye and of the Parts Adjoining . . 1 
 II. The Physiology of Vision — ^The Ophthalmoscope ... 12 
 
 III. Defects or Anomalies of Refraction and Their 
 
 Correction : Spectacles and Eye-glasses 26 
 
 IV. Strabismus, Cross-eye or Squint 52 
 
 V. The Influence of Optical Defects upon the Gen- 
 eral System 59 
 
 VI. School Life; Also Some Hints Regarding the Care 
 
 OF THE Eyes in General 73 
 
 VII. Artificial Lighting 101 
 
 VIII. Daylight Illumination of Rooms and Buildings 
 
 FROM AN Architectural Standpoint 117 
 
 IX. Diseases of the Conjunctiva 127 
 
 X. Diseases of the Eyelids, Lachrymal Apparatus, 
 
 Cornea, Iris and Vitreous . 154 
 
 XI. Diseases of the Interior of the Eye; Choroiditis, 
 
 Retinitis, Optic Neuritis and Optic Atrophy 171 
 
 XII. Some Visual Perceptions 180 
 
 XIII. Cataract 185 
 
 XIV. Glaucoma 196 
 
 XV. The Participation of the Eye in Diseases of the 
 
 General System 205 
 
 XVI. Wounds and Injuries 233 
 
 XVII. Effect of Certain Beverages and Drugs 273 
 
 XVIII. Color-Blindness 279 
 
 XIX. The Blind. Blindness from an Economic and 
 Social Point of View. The Education and Em- 
 ployment OF the Blind 283 
 
 XX. The Popular Movement for Conservation of Vision 327 
 
 V 
 
ILLUSTRATIONS 
 
 FIG. PAGE 
 
 1. Anterior Orifice of the Orbit with the Eyeball 2 
 
 2. Muscles of the Right Orbit 4 
 
 3. The Lachrymal Apparatus 6 
 
 4. Section of Human Retina 8 
 
 5. Crystalline Lens of New-born Child 9 
 
 6. Camera Obscura of a Photographic Apparatus 13 
 
 7. The Eye as a Camera 13 
 
 8. Lenses 14 
 
 9. Passage of Parallel Rays Through a Prism 15 
 
 10. An Emmetropic or Normal Eye 16 
 
 11. A Hypermetropic or Far-sighted Eye 16 
 
 12. A Myopic or Near-sighted Eye 17 
 
 13. Diagram To Illustrate Accommodation 18 
 
 14. Types for Testing the Eye 19 
 
 15. Binocular Field of Vision 22 
 
 16. Loring's Ophthalmoscope 24 
 
 17. Correction of Hypermetropia by a Convex Lens 28 
 
 18.4. Near-sighted Boy Trying To Read Without Glasses 36 
 
 18B. Same Boy with Glasses Properly Fitted 36 
 
 19. Correction of Myopia by a Concave Lens 39 
 
 20.4. View of School room, Showing How Room Looks to a Child 
 
 with Abnormal Eyes after He Has Been Properly Fitted 
 
 with Glasses 43 
 
 20B. Blurred Picture of Schoolroom, Showing How Room Looks 
 
 to a Child with Astigmatic Eyes 43 
 
 21. Astigmatic Dial 44 
 
 22. Cylindrical Lens 45 
 
 23. Correct and Incorrect Positions of Lenses 49 
 
 24. Showing an Increase in the Angle of Convergence of the 
 
 Optic Axis in Consequence of an Extreme Rotation of 
 
 One Eye 53 
 
 25. A Schematic Diagram of the Cerebrospinal and Sympathetic 
 
 Nerve Connections Between the Eye and the Stomach ... 63 
 
 26. Compensatory Positions of the Head in Paralysis of Eye 
 
 Muscles 67 
 
 27. Expressions Indicative of Overaction and Weakness of the 
 
 Muscles of the Eye 68 
 
 28. The Compressed Brow on One Side and the Elevated One on 
 
 the Other, Observable When the Eyes Are Not on the Same 
 
 Horizontal Plane 68 
 
 vii 
 
viii ILLUSTRATIONS 
 
 29. Showing Torticollis from Vertical Deviation of One Eye .... 69 
 
 30. Moiilthrop Movable and Adjustable School Chair 77 
 
 31. The '* Princeton" Adjustable Desk and Chair 78 
 
 32. Adjustable Desk and Chair 79 
 
 33-34. Adjustable Racks 80 
 
 35. Distortion of the Trunk While Working at a Too High Desk . 81 
 
 36. Specimens of Correct Type for Books 85 
 
 37. The Wrong Way To Use a Light 102 
 
 38. A Good Way To Light a Desk 103 
 
 39. The Wrong Way To Use a Table Lamp 104 
 
 40. The Correct Way To Use a Table Lamp 105 
 
 41. Dark Walls Waste Light and Prevent Diffusion 109 
 
 42. A Common Type of Fixture Planned To Give Diffused 
 
 Illumination Ill 
 
 43. Another Type of Fixture Designed To Give Diffused 
 
 Illumination 112 
 
 44. A Well-considered Side- wall Light 113 
 
 45. Proposed High School Building 121 
 
 46. Showing the Use of Prism Glass To Deflect the Light in a 
 
 Horizontal Direction 123 
 
 47. Illustrating the Uses of Prism Glass with Different Angles 
 
 of Reflection 124 
 
 48. Negro Baby with Ophthalmia Neonatorum 130 
 
 49. Corneal Abscess with Perforation 131 
 
 50. Opaque Cornea After Ophthalmia Neonatorum 131 
 
 51. Careless and Untrained Midwives Are Responsible for Much 
 
 Infantile Blindness 135 
 
 52. Nurse Applying Drops to Baby*s Eyes 136 
 
 53. New-born Baby Being Treated in Hospital for Babies' Sore 
 
 Eyes 137 
 
 54. A Typical Case of Advanced Trachoma Showing Numerous 
 
 Granulations 143 
 
 55. Kentucky Girl Suffering from Trachoma 143 
 
 56. Trachoma. Cicatrization Well Marked 143 
 
 57. Trachoma. Cicatrization Almost Complete 143 
 
 58. The Operation of Rolling or Expression 144 
 
 59. Trachoma and Other Infectious Eye Diseases Contracted by 
 
 the Use of Common Towels 145 
 
 60. Pterygium 153 
 
 61. Chalazion 156 
 
 62. Congenital Ptosis 158 
 
 63. Abscess of Lachrymal Sac and Mucocele . 160 
 
 64. Little Girl Leaning Over Chair, with Head Buried in 
 
 Cushion — Suffering from Corneal Ulcers 163 
 
ILLUSTRATIONS ix 
 
 65. Hutchinson's Teeth 165 
 
 66. Sarcoma of the Choroid 173 
 
 67. Scintillating Scotoma in Migraine 183 
 
 68. Swollen Opaque Lens After NeedUng 191 
 
 69. Incision of the Cornea for the Removal of Cataract 192 
 
 70. Expulsion of Lens Through Corneal Incision 192 
 
 71^. Microphotograph of Anterior Part of a Normal Eye 200 
 
 715. Microphotograph of Anterior Part of a Glaucomatous Eye 200 
 
 72. Incising the Eye at the Corneal Margin for Iridectomy 201 
 
 73. Iridectomy 202 
 
 74. Coloboma of Iris After Iridectomy 203 
 
 75. A Case of Exophthalmic Goitre 226 
 
 76. Erosion of Cornea from Finger-nail Injury 236 
 
 77. Adhesion of the Lid to the Globe After Lime Burn 237 
 
 78. Perforating Wound of the Cornea with Prolapse of the Iris . . 238 
 
 79. The Deadly Scissors and the Innocent Victim 239 
 
 80. Rupture of the Eyeball 243 
 
 81. Blood in Anterior Chamber Following Blow Upon the Eye . . . 244 
 
 82. A Great Many Cases of Loss of Sight Have Been Reported 
 
 as a Result of Curiosity of the Contents of Golf Balls .... 245 
 
 83. Man With Eyesight Destroyed and Face Badly Disfigured 
 
 by Burns From Molten Metal 248 
 
 84. Eye Protection Used by Babbitt Workers 249 
 
 85. Glasses Used by Workmen Pouring Babbitt 249 
 
 86. A Foundry Chipping Yard 250 
 
 87. Glasses Used by Workmen Chipping WTieels; also Burlap 
 
 Guard To Catch Flying Chips of Steel 250 
 
 88. Man With Hood of Brass Wire, Standing Before Furnace ... 251 
 
 89. Water Gauge Glass on Boilers, Protected With Brass 
 
 Casting 252 
 
 90. Glasses Used by Operator at Emery Wheel 253 
 
 91. Hammer, Sho^ving Chip 254 
 
 92. Warning Placard . 255 
 
 93. Mask Used by Operator To Protect Eyes and Face While 
 
 Using Electric Welding Machine 257 
 
 94. Glasses Used by Open Hearth Employees To Protect Eyes 
 
 While Looking in Open Hearth Furnaces 258 
 
 95. Electric Cataract 259 
 
 96. Three Bottles Containing Wood Alcohol Sold by Druggists 
 
 in New York City 262 
 
 97. Steel Chip in Lens 265 
 
 98. Patient in Position Before Giant Magnet 266 
 
 99. Skiagraph Showing Foreign Body in Eye 267 
 
X ILLUSTRATIONS 
 
 100. Taking X-ray for Supposed Foreign Body in Eye 268 
 
 101. The Pennsylvania Institution for the Instruction of the 
 
 BUnd, Overbrook, Philadelphia 290 
 
 102. The Swimming Pool 293 
 
 103. One Hundred Yard Dash. Start 295 
 
 104. One Hundred Yard Dash. Finish 295 
 
 105. School Gardens in June 297 
 
 106. Modeling 299 
 
 107. The Workroom 301 
 
 108. Facsimile of Type Used by Valentin Haiiy 304 
 
 109. American Braille Alphabet 306 
 
 110. Interlining Braille Slate 307 
 
 111. Hall Braille Writer. 308 
 
 112. Facsimile of Pencil Writing in ** Square Hand" by a Totally 
 
 Blind Girl 309 
 
 113. Form Study and Map Drawing 311 
 
 114. Senior Pupils Teaching Seeing Pupils, at the Clavier and 
 
 Piano 316 
 
 115. Senior Girls with Their Housemother in Their Cottage 
 
 Sitting-room 322 
 
 116. Piano Tuning and Repairing Is One of the Most Lucrative 
 
 Occupations for Capable Blind Men 325 
 
 117-118. Warnings Published by National Committee for the 
 
 Prevention of Blindness 330 
 
 PLATES 
 
 I. Horizontal Section of the Eyeball 6 
 
 II. Variations of the Fundus. Inflammations of the Retina. 
 Atrophy of Nerve in Locomotor Ataxia. Choked Disc in 
 Tumor of the Cerebrum 24 
 
HYGIENE OF THE EYE 
 
 CHAPTER I 
 STRUCTURE OF THE EYE AND OF THE 
 PARTS ADJOINING 
 
 To render the descriptions of the various affections 
 which will be treated of in the following pages more com- 
 prehensible, it has seemed desirable to give some intro- 
 ductory account of the anatomy and physiolog}^ of the 
 eyes and their appendages. Naturally, any attempt at a 
 complete or technical description of either of these sub- 
 jects would be foreign to the scope of this treatise, and 
 an effort will be made to present them in the briefest manner 
 compatible with clearness. 
 
 Such a delicate organ as the eye necessarily demands 
 most careful protection, not only from external injury, 
 but also from diseases of contiguous structures. Against 
 the former, nature has amply provided by furnishing a 
 bony framework into which the eye is set, so that only 
 its anterior one-third is exposed, and even this portion has 
 the covering of the lids and the interlacing eye-lashes, to 
 protect it when occasion demands. To give expression to 
 the w^orkings of the mind, and to endow the countenance 
 with charm and intelligence, the exposed part of the eye 
 has been made the most beautiful of all the structures of 
 the body and has well earned the designation of the poet 
 as " the mirror of the soul." 
 
 The bony receptacles in w^hich the eyes are lodged, the 
 orbits, are cone-shaped, with their widest portion directed 
 
2 HYGIENE OF THE EYE 
 
 forward, and as the long axis of each cone is more di- 
 vergent at its opening than at the apex, a maximum of 
 rotation is afforded to the eyes as they are pulled in various 
 directions by the action of the group of muscles with which 
 each is provided (Fig. 1) . In addition to the eyeball and 
 its muscles, the orbit contains a thick bolster of fat, which 
 surrounds the globe, protecting it from injury and per- 
 mitting of its free rotation by the ocular muscles. The 
 
 Fig. 1. — Anterior orifice of the orbit with the eyeball. Natural size. The tendons of the 
 four recti muscles are cut off near their insertion upon the eyeball, but the interior oblique, oi, 
 and the tendon, os, of the superior oblique are left entire. 
 
 configurement of the orbit depends in large measure upon 
 the shape of the skull and varies in different individuals 
 and in different races, being shallow in races with skulls 
 short in the anteroposterior axis, as exemplified in the 
 Indian, and deep where the same axis is elongated, as may 
 be noted in many European skulls. As the shape of the 
 orbit determines in large measure the form of the eyeball, 
 and, as we will see later, the state of the refraction in 
 each eye is dependent upon its length, it follows that near- 
 
STRUCTURE OF EYE AND PARTS ADJOINING 3 
 
 sightedness and far-sightedness are often the expression 
 of racial pecuharities of structure. 
 
 While the walls of the orbit are thin, to give less weight 
 to the skull, their margins are dense and strong, to re- 
 ceive the force of blows. This is particularly true of the 
 upper margins, where the protective power of the brow is 
 further augmented by a cushion of hair, the eyebrow, which 
 is formed of muscle and thick skin, covered with stiiF hairs. 
 The brow forms a conspicuous setting for the eye and 
 enters largely into facial expression. It also affords pro- 
 tection, by shedding perspiration. 
 
 With but one exception, the eocternal muscles of the 
 eye, six in number, arise from the apex of the orbit and 
 are attached to the globe near its equator. This arrange- 
 ment permits of the free movement of the eye in all direc- 
 tions, while the one muscle which has its origin near the 
 opening of the orbit is concerned chiefly with its easy 
 rotation ( Fig. 2 ) . These muscles receive their stimuli 
 from nerves which, together with the principal blood-ves- 
 sels, gain access to the orbit through a fissure in the apex 
 of the orbit. Another hole in the same position, the optic 
 foramen, permits the passage of the optic nerve with the 
 chief retinal blood-vessels into the skull. The muscles of 
 both eyes work in perfect harmony with one another, and, 
 by means of a wonderful complex mechanism of correlated 
 activity, rotate the eyes, either subconsciously or at the will 
 of the individual, in all directions. Any considerable inco- 
 ordination in their action is productive of double vision, 
 and the nice parallelism which is maintained by the per- 
 fect balance of all the muscles is destroyed and the affected 
 eye turns or squints (see p. 52). 
 
 The eyelids when closed form a perfect curtain for the 
 
4 HYGIENE OF THE EYE 
 
 eye, and when open an attractive setting for the organ of 
 vision. The lashes, with their graceful curve, are decora- 
 tive as well as protective to mechanical injury, and when 
 the lids are partially closed, their interlacing without ex- 
 cluding vision serves as a protection against excessive light. 
 They attain their maximum growth in about five months 
 and then drop out, being succeeded by new ones. Inflam- 
 
 FiG. 2. — Muscles of the right orbit. ("Motor Apparatus of the Eye," Stephens, Courtesy 
 
 F. A.Davis Co.) 
 
 matory conditions of the edge of the lids sometimes cause 
 the incoming lashes to assume a wrong direction and to 
 turn inward against the eye. They are then commonly 
 known as " wild hairs," and cause great distress and may 
 even give rise to serious inflammation of the eyeball. 
 Assuming that other inflammatory conditions of the eye 
 which are attended by sensations of pricking and irrita- 
 tion are also caused by wild hairs, it happens not infre- 
 quently that the ignorant pull out their lashes in the hope 
 of obtaining relief from the annoying symptoms, a use- 
 
STRUCTURE OF EYE AND PARTS ADJOINING 5 
 
 less procedure, as the lashes in such instances are not at 
 fault. 
 
 The movements of the lids are performed almost en- 
 tirely by the upper, the lower being almost stationary. 
 Upon the width of the opening between the lids depends 
 the apparent size of the eye and the expression of the in- 
 dividual. Racial characteristics find expression in the 
 almond eye of the Mongolian. In certain diseases of the 
 eye and the nervous system, the upper lids droop, giving 
 an expression of drowsiness and frequently necessitating 
 the throwing back of the head to enable the rays of light 
 to gain entrance to the pupils. 
 
 The eyelids, which are composed of muscle, elastic 
 tissue, and plates of cartilage which give form and firm- 
 ness to the lids, are covered by skin, which is but loosely 
 attached to the sublying tissues. This laxity of the super- 
 ficial tissues accounts for the great swelling which fre- 
 quently attends inflammations or follows injury of these 
 structures, and permits of the pufiiness under the lower 
 lids which frequently accompanies diseases of the heart 
 and kidneys. 
 
 The thin, delicate tissue, the conjunctiva, which covers 
 the anterior part of the globe and also lines the lids, is 
 continually lubricated by tears derived from the lachrymal 
 gland, a secreting organ the size of a filbert, hidden under 
 the outer portion of the roof of the orbit, and by mucus 
 derived from the conjunctiva itself and from a series of 
 small glands embedded in the edge of the lids. After 
 lubricating the eye and the conjunctival sac, the secre- 
 tions are sucked by two small apertures situated upon the 
 inner portion of each lid into the tear sac, with which they 
 are connected by two fine tubes. This sac, the size of a 
 
6 HYGIENE OF THE EYE 
 
 small pea, is situated just below the ligament which con- 
 nects the lids with the orbit, so that its emptying is facili- 
 tated not only by the contraction of its own muscular coat, 
 but also by the tension exerted upon it by the ligament of 
 the lids during the act of winking. The lachrymal sac 
 empties into the nose, through a bony canal at the lower 
 inner portion of the orbit. This canal and sac are lined by a 
 mucous membrane continuous with that of the nose and 
 
 Superior lacrimal gland 
 Inferior lacrimal gland 
 
 Upper eyelid partly 
 divested of skin 
 
 Upper punctum 
 
 Lacrimal sac, near it9 
 fundus 
 
 T. . X ■ ^ I II iiwiMiii I Common duct, formed 
 
 Ducts from supenor ^ ^^^^^^^tIIpO^^^^MIL by junction of upper 
 
 gland ^/^///Afllrv \^ ^^^^^^MT and lower ducts 
 
 Lower punctum 
 Naso-lacrimal duct 
 
 Fig. 3. — The lachrymal apparatus. ("Modern Ophthalmology," Ball, F. A. Davis Co.) 
 
 of the conjunctival sac, which accounts for the sympathetic 
 watering of the eye in so many nasal affections (Fig. 3) . 
 
 The eye itself is spheroid in form and about an inch in 
 diameter, being somewhat longer in its anteroposterior 
 than its vertical axis. It is suspended in the orbit by its 
 muscles and by a series of membranes or fascia to the walls 
 of the surrounding orbit. The layer of fat referred to 
 above fills out the remaining orbital space. 
 
 The outer layer, or envelope, the sclerotic, is a firm, 
 opaque, tough membrane, into the anterior part of which 
 the transparent cornea is set. The sclerotic maintains the 
 form of the eyeball and serves for attachment of the 
 
PLATE I. 
 
 CANAL OF/ 
 SCHLEMN 
 
 C/UARY 
 BODY 
 
 Horizontal section of the eyeball. Magnified about ZYi times (see PP- 7-10). ("Manual of 
 the Diseases of the Eye," Charles H. May, M.D.; Wm. Wood <k Co.) 
 
STRUCTURE OF EYE AND PARTS ADJOINING 7 
 
 muscles which move the eye. That portion immediately 
 smrounding the cornea and which is alone visible, forms 
 the so-called " white of the eye," the rest being hidden be- 
 hind the conjunctiva and orbital tissues. The cornea is 
 also tough and resisting, but perfectly transparent, to per- 
 mit the passage of rays of light into the eye (Plate I) . It 
 may be designated as " the window of the eye." Its outer 
 sm-face is smooth and preserves a high degree of polish, 
 and, being curved, returns, as a convex mirror, an erect 
 image of diminished size of any object before it. 
 
 Lying within the sclerotic, is the choroid, a membrane 
 rich in blood-vessels and pigment. The blood-vessels 
 nourish the interior of the eye and the pigment aids in the 
 absorption of excessive light. The quantity of pigment 
 varies, being plentiful in brunettes and sparse in blondes. 
 In albinos it is entirely absent. The choroid does not ex- 
 tend quite so far forward as the sclerotic, and merges 
 anteriorly into the ciliary body. 
 
 The third and essential coat is the retina. This is a 
 delicate sheet of nervous tissue, continuous with the brain, 
 through the medium of the optic nerve and its cerebral pro- 
 longations, and the rest of the eye may be regarded merely 
 as a mechanism for its protection and means of exposure 
 to external impressions ( Fig. 4 ) . The light-perceiving 
 elements of the retina are arranged in ten distinct layers, 
 held together by a connective-tissue framework. The most 
 important layer is that of the rods and cones, the latter 
 elements being especially concerned in the perception of 
 visual sensations, as these bodies are alone represented in 
 the macular region, a very minute area upon which the 
 rays concerned with the most direct and acute vision are 
 focussed. External to the laver of rods and cones is the 
 
8 HYGIENE OF THE EYE 
 
 pigment layer, in which is stored the retinal purple, a 
 photochemical substance which absorbs light and is con- 
 cerned in the transformation of the rays into visual im- 
 pulses. Just what the nature of this transformation is has 
 not been clearly determined, but, of course, there is no 
 
 ir 
 
 n 
 
 
 •' ^WK. 
 
 
 
 o 
 
 :^\ 
 
 '" ( )s'0/^,^, 
 
 ^0 O'OX <-A .'- - 
 
 ■ — a 
 —b 
 
 — b 
 —a' 
 — c 
 
 
 i^«^ 
 
 
 .^'/j 
 
 Fig. 4. — Section of human retina (Bohm and v. Davidoff) : a, a', outer and inner segments 
 of rods; b, b', outer and inner segments of cones; c, membrana limitans externa; d, outer nuclear 
 layer; c, outer plexiform layer; /, inner nuclear layer; g, inner plexiform layer; h, layer of ganglion 
 cells; i, fibre layer. Magnified 700 diameters. 
 
 actual picture capable of perception by another person 
 formed there. 
 
 The claim sometimes made, therefore, of the possibility 
 of detecting by posthumous examination of the retina the 
 object last regarded before death, is extravagant and 
 absurd. 
 
 The remaining portions of the eye are adapted to the 
 proper focussing of the rays of light entering the eye 
 through the cornea upon the retina, and in the regulation 
 
STRUCTURE OF EYE AND PARTS ADJOINING 9 
 
 of the amount of light entering the eye. The chief of these 
 is the crystalline lens ( Fig. 5 ) . This structure is a double 
 transparent convex lens or ordinary magnifying glass, but 
 of such consistency that its convexity may be readily 
 altered. It consists of connective layers composed of 
 minute fibrils, the outermost layers, or cortex, being softer 
 than at the central zone, or nucleus. As age advances, the 
 lens becomes harder and more resistant. It is contained 
 within an elastic covering and is suspended in the anterior 
 
 Fig. 5. — Crystalline lens of new-born child, seen from the side, showing the course of 
 the lens fibres. (Arnold.) Magnified 6 diameters. 
 
 part of the eye by a delicate ligament, a fine transparent 
 structure of fibrous tissue, and surrounded by a small cir- 
 cular structure, the ciliary body, the termination of the an- 
 terior extremity of the choroid coat. This body is divided 
 into two portions, a circular band of muscular tissue, the 
 ciliary muscle, and the ciliary processes. These latter, 60 
 or 70 in number, merge with the anterior portion of the 
 choroid and possess the power of pulling that membrane 
 forward. The ciliary body is a structure of great impor- 
 tance, as will appear later, for upon its action depends 
 the alteration in the shape of the crystalline lens and the 
 changing focus of the eye. 
 
10 HYGIENE OF THE EYE 
 
 The lens rests posteriorly in a cup-shaped depression 
 in the vitreous humor, a transparent gelatinous structure 
 which occupies four-fifths of the interior of the ball. This 
 humor fills out the form of the eyeball and gives support 
 to the retina, spread over its outer surface. 
 
 The amount of light entering the eye is regulated by 
 means of a circular curtain, the iris, its central aperture 
 forming the pupil. The iris lies upon the front of the 
 lens, its base of support and action being at the margin 
 of the posterior surface of the cornea, and the anterior 
 portion of the ciliary muscle. In addition to muscle fibres, 
 the iris contains pigment, the quantity of which determines 
 the color of the eye, the designation of the eyes as gray, 
 blue or black depending upon that factor. In albinos, the 
 pigmentation of the iris is absent, and the pinkish hue is 
 dependent upon the reflection through it of the red blood 
 in the vessels of the choroid. All eyes are blue at birth, 
 the commencement of permanent coloration taking place 
 about the sixth week. There is no truth in the popular 
 idea that dark eyes are stronger than light ones, except 
 in so far as they are better protected against excessive 
 light. It is a wise provision of Nature, that among South- 
 ern races dark eyes prevail, the better to protect against 
 the glare of a tropical sun, while in the North, light eyes 
 predominate. 
 
 The circular aperture in the iris, the pupil, is adapted 
 for the transmission of light into the eye, its size constantly 
 varying in response to variations in the quantity of light 
 which falls upon it. The change in the shape of the pupil 
 is effected by a double set of muscles in the iris, one of 
 circular fibres, contracting to make the pupil small in the 
 light, and one of dilating powers, to enlarge the pupil in 
 
STRUCTURE OF EYE AND PARTS ADJOINING 11 
 
 darkness. The pupil varies in size in different individuals, 
 and at different ages, growing smaller as age advances. 
 The pupil is larger, also, in near-sightedness than in far- 
 sightedness. Local affections within the eye, as well as 
 diseased conditions elsewhere in the body, affect its size; 
 various drugs have the same power also. 
 
 The space between the iris and lens and the arching 
 surface of the cornea is filled with an aqueous humor ^ which 
 has some refracting properties. The cornea and vitreous 
 also possess like qualities. These are constant, and but 
 slight in comparison with those of the lens. 
 
 The eyeball is richly supplied with blood-vessels and 
 nerves, apart from the great nerve of sight, the optic, and 
 it is by means of some of these latter that the change in 
 the size of the pupil is accomplished, acting under stimuli 
 from the brain centres. The chief source of vascular 
 supply to the retina is by means of a small artery which 
 enters the eye through the centre of the optic nerve. In 
 case of sudden stoppage of this vessel by a clot, instant 
 blindness ensues. 
 
CHAPTER II 
 
 THE PHYSIOLOGY OF VISION— THE 
 OPHTHALMOSCOPE 
 
 Of all the special senses, sight, perhaps, is the most 
 valuable and highly prized. It comprises the perception 
 and translation of impressions derived from external ob- 
 jects into cerebral conceptions. The explanation of the 
 visual act must therefore include the manner by which 
 impulses are conveyed from the exterior to the brain 
 centres, and something at least regarding the nature of the 
 impressions. How physical impulses are transformed into 
 vision we cannot say, nor have we, indeed, any knowledge 
 of other kinds of perceptions. 
 
 From an optical standpoint, all objects in nature are 
 divided roughly into luminous and non-luminous bodies; 
 light emitted from the former or reflected from the surface 
 of the latter moves in straight lines, and the smallest con- 
 ceivable line of light is called a ray. Of these rays we will 
 speak more hereafter. It will suffice at this time to say that 
 the great function of the eye is to collect these rays from 
 surrounding bodies, to focus them upon one of its parts, 
 the retina, whence the impressions are conveyed along the 
 optic nerve and higher brain tracts to the various visual 
 centres. The eye, therefore, resembles in its action a pho- 
 tographer's camera, of such intricate and wonderful con- 
 struction that it is always exposed for the receipt of im- 
 pressions from all distances, and can act either alone or in 
 harmony with its fellow, with a swiftness and accuracy that 
 no mechanical device can even approach, much less equal. 
 
 12 
 
PHYSIOLOGY OF VISION— THE OPHTHALMOSCOPE 13 
 
 In the camera, images of external objects are focussed 
 upon a sensitive plate and become permanent in conse- 
 quence of chemical changes induced by light; in the eye, 
 
 Fig. 6. — Camera obscura of a photographic apparatus. AB, object; Z>, diaphragm for 
 shutting off too divergent rays; L, lens for refracting the rays so that they will form the image 
 ab upon the sensitive plate R. 
 
 they fall upon the retina, where, after undergoing bio- 
 chemical change, they are conveyed to the visual centres in 
 the brain by the optic nerve. The eyeball itself, therefore, 
 
 Fig. 7.— The eye as a camera. AB, object; C, cornea, where the rays undergo a first refrac- 
 tion; D, the iris, that acts as a diaphragm for shutting off too divergent rays; L, lens, where the 
 rays are again refracted; R, retina, upon which the image ah is projected; a'fe' represents the 
 surface of a hypermetropic eye, and shows that the rays are not completely focussed, and conse- 
 quently the image must be blurred and indistinct; o"b" represents the surface of a myopic eye, 
 and shows a similar condition. 
 
 does not see, the act of vision being performed by the 
 brain. Figs. 6 and 7 compare the mechanism of a camera 
 with that of the eye. The sclerotic represents the sides 
 
14 
 
 HYGIENE OF THE EYE 
 
 of the box, the choroid its blackened inner surface, the 
 pupil forms the opening, and the crystalline lens and 
 cornea the focussing lens (e) , The iris serves as a dia- 
 phragm. The rays of light fall in the one case on the 
 sensitive plate, in the other on the retina. As the rays 
 of light cross in the eye, the retinal picture is an inverted 
 one, just as is the image in the magic lantern. The trans- 
 position of the image doubtless occurs in the brain, though 
 there are some who assert that the righting process takes 
 place in the retina itself. 
 
 Lenses. — A lens may be defined as a portion of glass 
 
 Fig. 8. — A, plano-convex: one side convex, the other plane. B, double convex: both 
 sides convex. When both sides are equally convex, as represented in the figure, the lens is 
 called biconvex. C, concavo-convex: one side concave, the other more convex. D, plano- 
 concave: one side concave, the other plane. E, double-concave: both sides concave. When 
 they are equally concave, as in the figure, the lens is called biconcave. F, convexo-concave: 
 one side convex, the other more concave. Either C ot F ia called a meniscus, or periscopic lens. 
 
 or other substance capable of transmitting light rays 
 bounded by one or more curved surfaces. Lenses that are 
 thickest at the centre are designated as convex lenses, those 
 thinnest at the centre as concave lenses. Convex lenses 
 have the property of collecting light rays, concave lenses 
 of dispersing them. According to the degree in which they 
 divert rays from their original source, lenses are designated 
 as strong and weak, the former bringing rays quickly to a 
 focus, the latter having their focus at a greater distance. 
 The standard now universally adopted in the notation of 
 
PHYSIOLOGY OF VISION— THE OPHTHALMOSCOPE 15 
 
 lenses is based upon the metric system and the unit from 
 which the gradations in the strength of lenses is reckoned 
 is the Dioptre, i.e.„ the focussing power required to bring 
 parallel rays to a focus at the distance of 1 metre. A lens 
 with twice this strength is designated as a 2 D. lens, and 
 has a focal distance of one-half metre. An 0.50 D. lens is 
 one with a focal distance of 2 metres (Fig. 8). 
 
 Lenses may be either spheric or cylindric. In the 
 former, light is refracted equally in all its planes, in the 
 latter, in one meridian only. 
 
 Prisms. — By a prism is meant a section of glass con- 
 sisting of two plane surfaces so inclined to each other that 
 
 Fig. 
 
 -Passage of parallel rays through a prism. 
 
 they form an angle. As it is the property of prisms to 
 deviate rays of light from the apex toward the base of the 
 prism, a prism placed before either eye with its base to- 
 ward the nose will deflect rays of light entering the eye, 
 and lessen convergence effort (Fig. 9). Prisms may be 
 ground into the lens, correcting any kind of refraction 
 error, and as their base may be placed at any axis, and 
 their strength accurately prescribed, they form one of the 
 most valuable means of correcting eye-strain in the ocu- 
 list's armamentarium. Prisms are not only of service in 
 removing the strain from weak muscles, but are often em- 
 ployed in exercising such muscles, the base of the prism in 
 
16 HYGIENE OF THE EYE 
 
 such cases being opposed in direction to the action of the 
 muscle which is to be strengthened. 
 
 All luminous rays reflected from a source at a dis- 
 tance greater than 15 or 20 feet are considered to be 
 parallel. When the object from which light is reflected is 
 brought nearer, rays entering the eye are divergent and 
 
 Fig. 10. — An emmetropic or normal eye. Parallel rays a and & are focussed upon the retina, while 
 divergent rays, as those proceeding from the point B, come to a focus behind the retina. 
 
 require to be more strongly bent or collected before they 
 focus upon the retina. This focussing property, of bend- 
 ing parallel rays of light from the distance and diverging 
 rays from near objects so that they meet upon the retina, 
 is termed refraction. 
 
 All eyes are not of equal length, some being shorter 
 
 FiQ. 11. — A hypermetropic or far-sighted eye. Parallel rays converge behind the retina, Rays 
 
 must be convergent in order to focus there. 
 
 and some longer than the average, or what may be con- 
 sidered to be the standard, eye. According, therefore, 
 to this variation in length, ocuhsts designate by the term 
 emmetropic, the eye of 7i07^mal length (Fig. 10), in which 
 rays of light entering the eye from a distance are brought to 
 a focus exactly on the retina. By the hypermetropic or far- 
 sighted eye (Fig. 11) is meant too short an eye, one in 
 
PHYSIOLOGY OF \^SION— THE OPHTHALMOSCOPE 17 
 
 which similar rays of hght are brought to a focus behind 
 the retina, and by myopic or near-sighted eye (Fig. 12), 
 too long an eye is designated, one in which the rays from a 
 distance are focussed in front of the retina. 
 
 Xot only may eyes vary in length, but, owing to a lack 
 of uniformity in the curvature of the cornea, different 
 meridians of the same eye have a different focus. In this 
 refractive condition, which is termed astigmatism, rays of 
 light w^hich pass through the meridian of greatest con- 
 vexity are brought to a focus sooner than those passing 
 through the meridian of least curvature. According to the 
 degree of corneal asymmetry, the type of astigmatism may 
 vary. In simple astigmatism, for example, one of the 
 
 Fig. 12. — A myopic or near-sighted eye. Parallel rays converge before reaching the retina. 
 Rays must be divergent in order to focus there. 
 
 meridians is emmetropic, the other hypermetropic or 
 myopic. In compound astigmatism, both meridians are 
 faulty, but unequal in degree. In mixed astigmatism, one 
 meridian is hypermetropic, the other myopic. 
 
 Accommodation. — In describing the various parts of 
 the eye, the crystalline lens was designated as a transpar- 
 ent biconvex lens, enclosed in a fibrous capsule, adaptable 
 to change of shape, by action of the circular structure which 
 surrounds it, the ciliary body. Unlike the camera, whose 
 lenticular focal distance may be changed by movement of 
 the sensitive plate backwards and forwards, the length of 
 the eyeball is fixed and constant, and alterations in its 
 focussing power performed by a change in strength of the 
 
18 
 
 HYGIENE OF THE EYE 
 
 refracting surfaces within the eye (Fig. 13) . As has been 
 stated, hght rays coming from a distance greater than 15 
 or 20 feet are parallel; those emanating from an object 
 situated nearer are divergent. To change the focus of the 
 eye, therefore, from the perception of distant objects to 
 those for near, its refracting power must be increased, and 
 the convexity of the crystalline lens increased by action of 
 the ciliary muscle. This adaptability of the eye is known 
 as the power of accommodation, and is made use of when- 
 ever there is the slightest change in the distance of any 
 
 PAR 
 
 NEAR 
 
 Fig. 13. — Diagram to illustrate accomraodation (after Helmholtz) . C.P., ciliary process; 
 7, iris; Sp.l, suspensory ligament; Z. cm., longitudinal ciliary muscle; c.c.m., circukr ciliary 
 muscle; c.S., canal of Schlemm. The left half represents the arrangement for viewing far 
 objects and the right half for viewing near objects. (Foster's "Text-book of Physiology," The 
 Macmillan Company.) 
 
 near object we look at. As life advances, accommodation 
 steadily declines. At 30 years of age, half of its power is 
 gone and at 45 years it is so weakened that small objects 
 near at hand are not perceived without additional focussing 
 power. At 60 years, accommodation is practically nil. 
 This decline in power is due to the increasing hardness in 
 the lens already referred to, in consequence of which the 
 ciliary muscle loses its power to increase its convexity. 
 This loss in power of accommodation due to advancing 
 years is termed presbyopia or old sight. 
 
 Visual Acuity. — ^The normal acuteness of vision has 
 
PHYSIOLOGY OF VISION— THE OPHTHALMOSCOPE 19 
 
 been determined to be the power the eye has of distinguish- 
 ing objects which subtend an angle of 5' upon the eye. 
 With this as a basis, Snellen, a distinguished Dutch oph- 
 thalmologist, constructed a series of letters made to con- 
 form to this standard. The accompanying diagram (Fig. 
 14) demonstrates that an object, in order to subtend the 
 same angle, must be larger the farther it is removed from 
 the eye. In conducting the test for visual acuity, a card 
 containing graduated series of letters of different sizes is 
 placed 6 metres distant from the observer and record made 
 of the smallest line of letters which the observer is able to 
 distinguish with each eye separately. If vision is normal, 
 
 / \ _^^?r^^ 
 
 
 D-60 
 
 J 
 
 viy 
 
 Fig. 14. — These types are so designed that the largest type shoyld be seen at 60 metres 
 by the normal eye, and the types range from this down to a size i-isible not farther off than 
 6 metres. 
 
 the line of letters designated as No. 6 will be distinguished 
 without difficulty. Lower degrees of acuteness indicate 
 some error in refraction or disease of the eye or of the 
 centres of sight in the brain. In general, the visual acuity 
 is expressed by a fraction, the numerator of which is the 
 distance at which the test is conducted, the denominator, 
 the line of type designated, i.e., vision 6/12 means that the 
 acuity is but one-half of normal, the line marked No. 12 
 on the card being seen at a distance of 6 metres. 
 
 The Field of Vision. — Thus far we have been con- 
 cerned with a description of direct vision, with the focussing 
 and refraction of rays which entered the eye in its principal 
 axis and are brought to a focus upon the centre of the 
 
20 HYGIENE OF THE EYE 
 
 retina, the macula lutea, so-called. Though less sensitive, 
 the periphery of the retina is also capable of receiving im- 
 pressions and transmitting them through the retina to the 
 optic nerve and thence to the brain. This peripheral per- 
 ception is termed indirect vision, and by it the eye is made 
 conscious of objects outside the area of direct vision. The 
 area embraced by direct and indirect vision is designated as 
 the field of vision, and varies in extent according as the eye 
 is directed upon a near or far object. By means of this 
 function, there is a visual consciousness of a wide area of 
 objects seen indirectly, and when this area is lessened by 
 disease within the ejQ or impairment of the visual tracts 
 and centres governing vision, the perceptive powers of the 
 individual are greatly restricted. 
 
 If an individual station himself with his back to a 
 window at a distance of two feet from a screen, and with 
 one eye blindfolded direct his gaze upon his finger pressed 
 against the screen directly in front of his eye, while with 
 his free hand he brings a small square of white paper from 
 the extreme periphery slowly inwards towards the finger 
 point at which the eye is directed, the first conscious ap- 
 pearance of the paper will determine the extent of his 
 visual field in that particular meridian, and if this pro- 
 cedure be repeated until all the meridians encircling the 
 fixing finger be tested, he may map out roughly the 
 entire extent of his visual field. If small pieces of colored 
 paper are then substituted for the white, he will obtain the 
 dimensions of what is termed the color field. This will be 
 noted to be peripherally smaller than that for white, and if 
 some designation of the point at which the colors are first 
 seen is recorded on the screen, it will be noted that these are 
 not all seen at the same point, but that blue will be per- 
 ceived before red and red before green, etc. 
 
PHYSIOLOGY OF \^SIOX— THE OPHTHALMOSCOPE 21 
 
 Defects in the visual field may vary from loss of the 
 entire field of indirect or peripheral vision, with the con- 
 servation of that of the central or fixation point alone, to 
 the production of small blind areas or scotomas, scattered 
 throughout the field. These minute blind spots, produced 
 by disease, must not be confused with the physiological 
 blind spot (Mariotte's blind spot) which corresponds to 
 the position of entrance of the optic nerve within the eye, 
 and which is situated somewhat to the outer side and below 
 the fixation point. 
 
 Loss of half of the field of vision, termed hemianopsia, 
 especially when associated with a corresponding loss in the 
 fellow eye, is veiy significant of brain disease, and in asso- 
 ciation with a speech defect often follows apoplectic at- 
 tacks. Blindness in the outer halves of the field of vision 
 of both eyes is significant of disease of the pituitary body, 
 and is often seen in connection with giantism and certain 
 sexual characteristics. 
 
 Each eye not only possesses its own field of vision, but 
 one in common vAih. the fellow^ eye. The simultaneous use 
 of both eyes is called binocular vision, and it is by the har- 
 monious blending of images focussed upon corresponding 
 parts of the two retinae that the brain receives but a single 
 impression. By means of binocular vision, we are enabled 
 to form a much better impression of distances and of the 
 form or solidity of objects. The accompanying diagram 
 (Fig. 1.5) demonstrates the area of the combined fields of 
 vision. 
 
 The determination of the extent of the visual field, more 
 accurately determined, and registered by an apparatus 
 termed the perimeter, is in common use by all oculists and is 
 of inestimable value, not only in determining the nature and 
 extent of intra-ocular diseases, but also the location of many 
 
22 HYGIENE OF THE EYE 
 
 affections within the brain which affect the centres of sight. 
 Ocular Muscles. — ^The range and extent of the field 
 of rision is greatly increased by the rotation of the eyes by 
 the extra-ocular rnuscles. Each eye moves in perfect 
 unison with its fellow, and always with the maintenance of 
 symmetrical points of the retinal images. If this har- 
 monious action of the muscles moving the eyes be disturbed, 
 single vision is no longer possible, and double vision re- 
 sults, usually with some apparent deviation of the eyes 
 from the normal parallelism of their axes. In other words, 
 the eyes are crossed. This is observed in paralyses of one 
 
 Fig. 15. — Binocular field of vision. (Mcser.). The line L bounds the field of vision of the 
 left eye, the line R that of the right eye. The central white area Ifr marks the field of vision 
 common to both eyes. 
 
 or more of the eye muscles, such as occurs in consequence 
 of some serious local or systemic disease. 
 
 Less serious but often no less disturbing phenomena 
 are occasioned much more frequently by slighter anomalies 
 in the structure or nerve supply of the ocular muscles. In 
 this class of cases, the heterophorias, so-called, there is no 
 apparent departure from the harmonious dual action of the 
 eyes, and single vision is still maintained. This main- 
 tenance of single vision and the avoidance of double vision 
 is attained, however, only after severe effort upon the part 
 of the weak muscles, and a chain of symptoms is evoked 
 which is designated under the term of muscular weakness 
 or muscular asthenopia. Dizziness, headache, digestive 
 
PHYSIOLOGY OF VISION— THE OPHTHALMOSCOPE 23 
 
 disturbances, and ocular discomfort at all distances, are 
 some of the subjective symptoms evoked by these latent 
 muscle errors. A consideration of true cross-eye, squint, 
 or strabismus will be given later. 
 
 The Ophthalmoscope 
 
 Prior to 1851, the interior of the eye had never been 
 explored and there was no knowledge of the conditions 
 which interfered with vision other than those apparent by 
 inspecting the anterior segment of the eye. In this year, 
 however, von Helmholtz, the great physicist, produced an 
 instrument termed the ophthalmoscope, by means of which 
 it became possible to illuminate the fundus or back part of 
 the eye, and to study under considerable magnification the 
 many diseased conditions which were formerly the sub j ects 
 of theoretical speculations. This discovery was undoubt- 
 edly one of the greatest achievements in physical science, 
 and, as will presently be learned from the description of 
 what the ophthalmoscope unfolds, has been of incalculable 
 benefit to medicine. 
 
 The ophthalmoscope consists primarily of a concave 
 silvered mirror with a central perforation, behind which are 
 placed a number of convex and concave lenses set into a 
 disc, which is capable of rotation, so that any one of the 
 series of lenses may be brought before the aperture (Fig. 
 16) . The ophthalmoscopic examination is made in a dark- 
 ened room, the patient being placed in front and somewhat 
 to the side of a single source of illumination. The ex- 
 aminer, stationing himself before the patient, with the cen- 
 tral aperture in the mirror held close to his eye, collects the 
 rays of light from the lamp upon the mirror of the oph- 
 thalmoscope and directs them upon the eye to be examined. 
 The patient is then requested to direct his gaze directly in 
 
24 HYGIENE OF THE EYE 
 
 front of him, while the examiner, with relaxed accommoda- 
 tion, slowly approaches to within a few inches of the pa- 
 tient's eye, keeping the pupil steadily illuminated. To one 
 versed in the art of ophthalmology, the interior of the eye 
 is at once visible, and may be studied without inconvenience 
 
 Fig. 16. — Loring's ophthalmoscope; front view. The perforated mirror in this case 
 is cut into a quadrangular shape, so that it can be rotated slightly from side to side (tilting 
 mirror). This is to make the reflection of light less oblique in using the direct method. The 
 lower disc contains a series of lenses which can be rotated by the pressure of the finger on the 
 serrated edge of the disc, so that any desired lens can be brought in front of the sight-hole. 
 Usually there is added a quadrant on the back, containing additional lenses, which being super- 
 imposed over those in the revolving disc make a great variety of combinations. 
 
 or strain to the patient or observer for a protracted intei^al. 
 By means of the lenses which may be brought into the line 
 of vision, it is possible to measure with considerable ac- 
 curacy any errors of refraction present. 
 
PLATE II. 
 
 A, the ttlbinotic fundus; albino and light blonde. B, the tessellated fundus; brunette (see p. 25). 
 C, albuminuric retinitis and neuritis orcurrinK in pregnanfy (see p. 210), D, atrophy of retina 
 nerve and choroid following disseminated chorioretinitis luetica (see p. 172). E, atrophy of optic nerve 
 in locomotor ataxia (see p. 232). F, choked disc in tumor of the cerebrum (see pp. 178-228). 
 (Posey and Spiller.) 
 
PHYSIOLOGY OF VISION— THE OPHTHALMOSCOPE 25 
 
 Precise measurement of the refraction of the eye is 
 accomplished by observing the direction in which the Hght 
 appears to move across the pupil as the mirror held close to 
 the observer's eye is rotated in the vertical and horizontal 
 meridians. In the application of this test, which is termed 
 retinoscopy, or the shadow test, the observer stations himself 
 at a metre's distance from the patient, and superimposes 
 lenses of various kinds and degrees before the patient's eye 
 until the requisite change in direction of the movements of 
 the light is attained. To insure accuracy, complete pupil- 
 lary dilatation by the instillation of some drug to accomplish 
 this purpose is necessary. When properly performed, this 
 test is one of exceeding accuracy, and enables the examiner 
 to ascertain not only the amount of far- and near-sighted- 
 ness present, but also the axis and degree of the astigmatism. 
 
 The picture of the interior of the eye revealed by the 
 ophthalmoscope is one of great beauty. Varying in shade, 
 depending upon the amount of pigmentation, being lighter 
 in blondes and darker in brunettes, the fundus presents a 
 uniformly pinkish-yellow appearance, broken by the red- 
 dish walls of the retinal arteries and veins, as they course 
 over the retina in their exit and entrance in the optic nerve. 
 The head of this structure is plainly visible, and presents 
 itself as a small pinkish-white plaque, surrounded by a fine 
 layer of pigment, which defines its edges from the surround- 
 ing tissues. Xot far from the outer side of the nerve is 
 the macula lutea, the most highly sensitized of all the parts 
 of the retina, as it is upon this point that the central rays 
 of light are converged. This important area is darker than 
 the rest of the fundus, with a small bright spot in the centre 
 called the fovea centralis. The variations from this healthy 
 or physiological appearance of the fundus will be discussed 
 in future chapters (Plate II, A and B) , 
 
CHAPTER III 
 
 DEFECTS OR ANOMALIES OF REFRACTION 
 AND THEIR CORRECTION 
 
 SPECTACLES AND EYE-GLASSES 
 
 As we have already seen, by the refraction of the nor- 
 mal eye is meant the power the eye has of so acting upon 
 the rays of light passing through the pupil that they are 
 converged upon the retina. This is accomplished without 
 eiFort or strain unless the power of the eye be taxed unduly. 
 If, however, the build of the eye departs from the normal 
 and its length is too short, as in the far-sighted eye, or too 
 long, as in the near-sighted eye, clear vision is attained only 
 by the exercise of strain or, as is the case in the near-sighted 
 eye, by the aid of suitable glasses. 
 
 Far-sightedness or Hypermetropia. — As may be 
 seen by the diagram of a far-sighted eye (see Fig. 11), by 
 reason of its deformity in length, entering parallel rays of 
 light are not brought to a focus upon the retina, but unite 
 some distance behind this membrane, this distance varying 
 in amount with the length of the eye. Under such conditions 
 clear vision is impossible. Happily, however, the eye is 
 equipped with a mechanism which can readily correct this 
 lack of refraction power and bring parallel rays of light to 
 a shorter focus. This consists in increasing the refractive 
 power of the crystalline lens by a spontaneous and volun- 
 tary contraction of the ciliary muscle. In the normal eye 
 the ciliary muscle is relaxed in distant vision, coming into 
 action only when the eye focusses on a near object. In 
 hypermetropia, however, sharp vision both for far and near 
 
DEFECTS OR ANOMALIES OF REFRACTION 27 
 
 is only obtained through the aid of this important muscle, 
 the degree of its contraction varying with the demand 
 placed upon it, being greater the higher the degree of the 
 far-sightedness and vice versa. 
 
 This constant and unnatural demand upon the ciliary 
 muscle, however, after a time is associated with evil con- 
 sequences. In the young and vigorous the strain may be 
 maintained for a long time without perceptible disadvan- 
 tage, but in older subjects and those with impaired health, 
 symptoms of fatigue of the ciliary muscle soon manifest 
 themselves. These may express themselves in a variety of 
 ways. In the first place, vision is not always clear, and this 
 is particularly true of near vision. As we have seen on 
 page 18, the perception of near objects is accomplished by 
 the act of accommodation, v/hich consists in increasing the 
 convexity of the crystalline lens by action of the ciliary 
 muscle. Precisely the same mechanism is employed to 
 overcome far-sightedness. When a far-sighted eye is called 
 upon to accommodate for a near object, it has already ex- 
 pended some of its power in overcoming its deficiency in 
 length, and has lost considerable of its reserve accommoda- 
 tive power. If the degree of far-sightedness is consider- 
 able, therefore, or if the ciliary muscle has been weakened 
 by a general state of muscular weakness, or, what is more 
 important, if the lens has become harder from age and 
 requires greater muscular contractability to affect its 
 curvature, the perception of the eye for small ob j ects close 
 at hand is much impaired, if not entirely lost. In moder- 
 ate amount of far-sightedness, the strain on the ciliary 
 muscles evidences itself by blurring of the type, for ex- 
 ample, in reading, or a running-together of the stitches in 
 sewing. In far-sightedness of high degree, even distant 
 
28 HYGIENE OF THE EYE 
 
 vision may be impaired, the ciliary muscles being unequal 
 to the strain of maintaining a constantly increased curva- 
 ture of the lens for a protracted period. 
 
 The activity of the ciliary muscle may also give rise to 
 deleterious changes within the eye itself and the structures 
 neighboring upon the globe. Continuous contraction of 
 the ciliary muscle means an increase in the amount of 
 blood within the muscle, to provide for its nourishment and 
 maintenance. Contiguous structures, such as the choroid, 
 retina, and optic nerve, also participate in this state of 
 hypersemia, as it is called, and mild inflammatory changes 
 are evoked, which give rise to symptoms emanating from 
 
 A 
 L 
 
 Fig. 17. — Correction of hypermetropia bj- a convex lens. The eye is drawn of the natural 
 size of a hj-perme tropic eye having an axial length of 21 mm. 
 
 these tissues. Sensitiveness to light is complained of and 
 the eyes become red and irritable; the conjunctiva and 
 lids also sharing in the hypersemia, become inflamed also. 
 JNIuscular activity necessitates the expenditure of ner- 
 vous force also, and in consequence of the maintenance of 
 the ciliary muscles in a state of continuous action, constant 
 impulses must be sent from the brain for their innervation. 
 Headache is originated and a series of nervous reflexes, 
 which will be treated of in a subsequent chapter. Owing 
 to the strain placed upon the muscles rotating the eyeballs 
 inward, far-sightedness of high degree frequently gives 
 rise to strabismus or cross-eye (see p. 52) . 
 
DEFECTS OF ANOMALIES OF REFRACTION 29 
 
 The optical principles involved in the correction of far- 
 sightedness are extremely simple, consisting merely in the 
 determination of the far-sightedness, and the removal of 
 the strain upon the ciliary muscles, by the superposition 
 before the eye of a convex lens equal in amount with the 
 refraction error (Fig. 17). This auxiliary lens at once 
 removes the necessity for the increased curvature of the 
 crystalline lens, and the ciliary muscle is again placed at 
 rest, in so far at least as distant vision is concerned. 
 
 Although the optic principles involved are simple, the 
 prescribing of glasses in far-sightedness is often a matter 
 of some complexity. In the first place, the degree of far- 
 sightedness is not always the same in all the meridians of 
 the eye, and the complication of astigmatism may be pres- 
 ent. Secondly, there is some dispute regarding the proper 
 manner of determining the amount of hypermetropia pres- 
 ent. ]Most cautious and thorough ophthalmologists claim 
 that this can only be accomplished, in subjects under 40 
 years of age, by the local use of some drug which will sus- 
 pend the action of the ciliary muscle. Others, chiefly opti- 
 cians and optometrists, who are not permitted by law to 
 employ any form of drugs in their examinations of the 
 eye, assert that this is unnecessary and that accurately pre- 
 scribed lenses may be given without putting the ciliary 
 muscles at rest. 
 
 Were the eye but a camera, a fixed and stable optical ap- 
 paratus, and the regulation of its focussing apparatus un- 
 associated with muscle spasm, it would be a simple matter 
 to determine the degree of far-sightedness present by ascer- 
 taining the strongest convex lens by means of which the 
 sharpest degree of distant visual acuitj^ was attained. After 
 40 years of age, the eye approaches in a manner the sta- 
 
30 HYGIENE OF THE EYE 
 
 bility of such a fixed optical instrument, for, as we have 
 seen, after that age the lens becomes so hard that the 
 ciliary muscle has but little power to change its shape. 
 In subjects over 40 years of age, therefore, satisfactory 
 results may usually be attained in this manner. In younger 
 persons, however, an active muscle, operating upon a flexi- 
 ble lens, has to be taken into consideration, as well as the 
 deleterious effects which may have arisen in the eye in 
 consequence of the vicious use of that muscle. It would 
 be beyond the scope of this work to enter into a full dis- 
 cussion of all the optical principles involved in refraction, 
 and to attempt an explanation of the various changes which 
 occur in the ciliary muscle in errors of refraction. It may 
 be stated, however, that in far-sightedness, in consequence 
 of the extra work placed upon it, the ciliary muscle becomes 
 excessively strong, and hypertrophies. Its contractions 
 frequently become spasmodic and render all attempts to 
 estimate the degree of the refraction error extremely diffi- 
 cult. Before the exact amount of far-sightedness present 
 in any eye under 40 years of age can be accurately deter- 
 mined, therefore, some means must be used to eliminate the 
 action of this muscle and to prevent its contractions modi- 
 fying the results of the examination. Fortunately, such 
 means are afforded by a class of drugs termed " mydri- 
 atics " or, better, " cycloplegics," drugs which have the 
 power of dilating the pupil and temporarily suspending 
 the power of the ciliary muscle. 
 
 These drugs are of two classes, the quick-acting, of 
 which homatropin is the type, and atropine, a derivative of 
 belladonna, whose effects are much more lasting. Gen- 
 erally speaking, atropine is the ideal drug for refraction 
 purposes, for it not only assures a complete abeyance for a 
 
DEFECTS OR ANOMALIES OF REFRACTION 31 
 
 time of all action of the ciliary muscle, but it secm-es for 
 the tissues of the eye a needful rest, which is often most 
 essential after the eye tissues have been long subjected to 
 the effects of strain. As we shall see in the description of 
 near-sightedness, a large proportion of near-sighted eyes 
 develop from uncorrected far-sighted eyes, whose tissues 
 have been strained and softened by the unnatural strain 
 placed upon them. In such eyes, the prolonged use of 
 atropine is invaluable, the softening and stretching proc- 
 ess being entirely arrested by it. In children, the coats of 
 whose eyes are weak and yielding and whose ciliary muscles 
 are strong and active, atropine is the drug of choice. 
 
 The objections to atropine are the length of time neces- 
 sary to complete the test, the effects of the drug lasting 
 for about ten days to two weeks, and the constitutional 
 symptoms which appear at times after even one instillation 
 of the drops. The first objection is readily met by a con- 
 sideration of the advantages to be derived from this short 
 interruption of work or pleasure. Unless the condition of 
 the eyes to be refracted shows signs of urgency, the refrac- 
 tion test under atropine, in the case of school children, can 
 usually be postponed until the holidays, and in other cases 
 few employers will grudge an employee sufficient time to 
 gain a greater efficiency in his work by obtaining proper 
 ocular treatment. 
 
 The constitutional symptoms which occasionally ap- 
 pear, though made much of by optometrists and others 
 who are prevented by law from employing drugs of any 
 kind in their refraction work, are usually very slight, and 
 pass away rapidly after the cessation of the treatment. A 
 diminished dosage in children and refraining from the use 
 of atropine in extremely warm weather are usually the 
 
32 HYGIENE OF THE EYE 
 
 only safeguards necessary to be observed. Another objec- 
 tion is sometimes made that atropine may precipitate an 
 attack of glaucoma. In elderly persons predisposed to 
 glaucoma, such accidents have been known to occur, but 
 may easily be prevented by the careful systematic examina- 
 tion of the eyes which should precede the instillation of 
 drugs of any kind for refraction or other purposes. Most 
 eye surgeons of experience have treated thousands of cases 
 without having this unfortunate accident happen. 
 
 Near-sightedkess^ Myopia. — Diametrically opposite 
 to the far-sighted eye is the near-sighted or myopic eye, for 
 in this anomaly of refraction the eyeball is too long, and 
 rays of light coming from a distance are brought to a focus 
 in front of the retina. We have seen how the far-sighted 
 eye may secure clear distant vision by a contraction of the 
 ciliary muscle, but in myopia such an increase in the focus- 
 sing power of the eye only accentuates the difficulty, nor 
 is there any other mechanism possessed by the near-sighted 
 eye which enables it to overcome its visual deficiency, so 
 that the myope is dependent entirely upon the artificial aid 
 of lenses to see distant objects clearly. By squinting the 
 lids, and excluding some of the marginal rays entering the 
 eye, the myope is enabled to see somewhat clearer, but the 
 degree of visual clearness obtained by this means is verj^ 
 slight. 
 
 As has been stated in an earlier chapter, the shape of 
 the skull frequently determines the conformation of the 
 orbit, which, in its turn, moulds the form of the eyeball. 
 Myopia, therefore, occurs most commonly in races like the 
 Teutonic, whose skulls are long in the anteroposterior di- 
 ameter, and is but rarely met with in the negro and Indian, 
 where the converse is the rule. 
 
DEFECTS OR ANOMALIES OF REFRACTION 33 
 
 Owing probably to the transmission of the shape of the 
 skull favoring the development of myopia, this error of 
 refraction is often hereditary, being transmitted through 
 several generations and often occurring among many mem- 
 bers of the same family. Myopia is but rarely congenital, 
 generally developing from the eighth to the tenth year, its 
 appearance at that time in eyes formerly emmetropic or 
 far-sighted being traceable to (a) the hereditary influence 
 just referred to, (b) unusual strain upon the eyes, either 
 from overuse or use under improper conditions of lighting, 
 etc., (c) ill health, or (d) to some irregularity in the corneal 
 curvature, or haze of the refracting surface of the eyes, 
 which impairs, though but slightly, the proper focussing of 
 the rays of light upon the retina. 
 
 As we have seen, the myopic eye is too long an eye. 
 Emmetropic and hypermetropic eyes become myopic in 
 consequence of a stretching in their coats, a process which 
 is never physiological and is accompanied by more or less 
 danger to the ocular structures. Myopia exhibits also a 
 marked tendency to be progressive, the degree of the near- 
 sightedness tending to increase year by year until the proc- 
 ess is arrested. This arrest in the stretching process usu- 
 ally happens in healthy subjects whose eyes are not 
 subject to too great strain, between the ages of 20 and 30 
 years, but in some cases it continues through life, and, being 
 always attended with evil consequences to the integrity of 
 the eyeball, may cause such damage that the eye no longer 
 is possessed of useful vision. Indeed, in some cases the 
 damage suffered is so great that the removal of the eye 
 is necessitated for the relief of pain and other inflammatory 
 symptoms. To show the effect of school life upon the 
 eyes the following percentages of Cohn, a German oph- 
 
34 HYGIENE OF THE EYE 
 
 thalmologist, who made extensive researches some 50 years 
 ago, with a view to determining the incidence of myopia in 
 Germany, are of interest : 
 
 Percentage of myopia 
 
 Five village schools 1.4 
 
 Twenty elementary schools 6.7 
 
 Two higher girls' schools 7.7 
 
 Two intermediate schools 10.3 
 
 Two real-schulen 19.7 
 
 Two gymnasiums. 26.2 
 
 Among the students of the university, Cohn found the 
 percentage of myopic eyes had advanced to 59.5. His con- 
 clusions demonstrated that not only does the number of 
 short-sighted pupils increase from the lowest to the highest 
 schools, but that the increase is in direct proportion to the 
 length of time devoted to the strain of school life. In 1885, 
 Risley and Randall compiled a similar group of statistics 
 based upon the examination of a large number of eyes by 
 competent American oculists, and found an analogous, 
 though somewhat lower continuous progression in the per- 
 centage of myopia in American schools. In 1907, the 
 author, in conjunction with Dr. R. Tait McKenzie, Di- 
 rector of the Department, in his capacity as Ophthalmol- 
 ogist to the Department of Physical Education in the 
 University of Pennsylvania, made an analytical study of 
 the eyes of 883 students in the various departments of that 
 institution. In the comparison which was made to ascer- 
 tain the influence of age and study on the refraction, it was 
 found that among 633 students in the two lower classes, 
 87.25 per cent, were hypermetropic and 12.75 per cent, 
 were myopic, while of 261 students in the upper classes, 
 80.25 per cent, were hypermetropic and 19.75 per cent. 
 
DEFECTS OR ANOMALIES OF REFRACTION 35 
 
 were myopic. The average of all the scholars examined 
 was 21.4 years, and the statistics showed an increase of 
 about 2.5 per cent, of myopia for each year during the 
 four years of college life. Five per cent, more of myopia 
 was found in the professional departments in scholars of a 
 similar age than in the college department, this being 
 doubtless accounted for by the fact that most of the scholars 
 in the college come from private or city schools, where the 
 eyes are properly protected, while the scholars in the pro- 
 fessional schools come from rural communities, where ac- 
 curate refraction is impossible and the care of the eyes 
 neglected. 
 
 In addition to the professional classes, many artisans 
 whose work entails prolonged and taxing eye work become 
 myopic. Hebrews, owing perhaps to racial peculiarities of 
 skull, are often near-sighted, frequently to the highest 
 degree. 
 
 On account of their poor vision, myopes without glasses 
 are greatly handicapped in many waj^s. Thus individuals 
 with this build of eyes often manifest a strong distaste 
 for all outdoor sports in which sharp vision is a requisite, 
 and acquire a marked predilection for indoor occupations, 
 painting, books, etc., a taste which is especially unfortunate, 
 as prolonged near work of all kinds only aggravates their 
 difficulty and adds to their ocular deficiency. In conse- 
 quence of their inability to note the expression of those with 
 whom they come in contact, the myope often develops an 
 abstracted and even a stupid expression of countenance, 
 and exhibits a degree of shyness not so frequently seen in 
 those with normal vision. Although there may be but 
 slight strain placed upon their ciliary muscles, uncorrected 
 near-sightedness frequently gives rise to headaches and the 
 
36 
 
 HYGIENE OF THE EYE 
 
 other symptoms enumerated elsewhere as the consequence 
 of eye-strain. 
 
 The diagnosis of near-sightedness, when present to an 
 appreciable degree, may be suspected, when in addition to 
 poor distant vision the subject is able to read the finest type 
 with the greatest ease, provided the book or magazine is 
 brought close enough to the eyes (Fig. 18). 
 
 Fig IS.i. — This near-siiilited boy is trying to read without glasses and is in danger of 
 serious trouble later if neglected. Properly fitted glasses would add to the boy's comfort and 
 appearance, as well aa provide insurance for his future. 
 
 Fig. ISB. — When glasses are properly fitted, comfort and safetj' are secured. 
 
 Upon ophthalmoscopic examination, the observer will 
 note certain characteristic changes in the fundus dependent 
 in degree and extent to the amount of stretching which the 
 eye has undergone. Most constant of these is a crescentric 
 area of partial and complete atrophy of the choroidal and 
 retinal elements to the outer side of the optic nerve, which 
 
DEFECTS OR ANOMALIES OF REFRACTION 37 
 
 in high grades of myopia may extend to and even involve 
 the area of most distinct vision. 
 
 By reason of the lessened demand upon accommodation, 
 correlated convergent efforts are also diminished and 
 myopic eyes frequently become divergent. 
 
 The eyeball being elongated unduly, the vitreous is no 
 longer adequate to fill the space it occupies under normal 
 conditions, and becoming disorganized by the attendant 
 choroidal disease, becomes fluid and more or less filled with 
 opacities, which float to and fro with the movements of the 
 eyes and occasion the motes or muscce volitantes, which be- 
 come a source of great annoyance. Finally, as a result of the 
 lack of support given it by the altered vitreous and weak- 
 ened by the sublying choroidal disease, the retina, in re- 
 sponse to some slight tap upon the eye or to some jar of the 
 body, floats loose from its attachments and encroaches upon 
 the space normally occupied by the vitreous. Loss of sight 
 in the area occupied by the detachment follows, and unless 
 reparative measures be properly applied, and. unfor- 
 tunately in many cases, even in spite of the most prompt 
 and best medical care, total blindness may ensue. 
 
 From the foregoing it must be evident that myopia is 
 a pathological condition of the eyes which demands the 
 most careful consideration, not only of the oculist but the 
 layman as well. There is a more or less general impres- 
 sion that near-sighted eyes are stronger than others, and 
 on account of ease in reading, etc., myopes not infrequently 
 transgress the laws of prudence and prolong the use of the 
 eyes at close work beyond reason. Often it would appear 
 as though the tax was without deleterious consequences, 
 and the eyes apparently tolerate years of abuse without 
 giving signs of failing. By middle life, however, the 
 
38 HYGIENE OF THE EYE 
 
 changes wrought by misuse rarely fail to manifest them- 
 selves, and the unfortunates who have persisted in the mal- 
 treatment of their eyes are now forced to be sparing of 
 their use, at a time when physical limitations curtail the 
 enjoyment of participation in an active outdoor life and 
 necessitate sedentary habits. The prevention and correc- 
 tion of myopia, therefore, is a problem of great sociologi- 
 cal as well as medical significance, and it must be a matter 
 of gratification to their countrymen that American oculists 
 for many years have devoted much study and effort to 
 its solution. 
 
 The prevention of myopia includes a steadfast and 
 intelligent observance of all the details enumerated in 
 Chapter VI, but especial emphasis must be laid upon the 
 necessity for an early examination of all children's eyes, 
 with a view to ascertaining the state of the refraction, and 
 for the prompt and efficient correction of any errors which 
 may be found. The laity must disabuse its mind that the 
 wearing of glasses has any weakening effect upon the eyes, 
 and must appreciate that the most potent factor to pre- 
 vent the progress of ocular deficiencies is properly adjusted 
 glasses. One of the most pathetic, and unfortunately a not 
 uncommon experience of the oculist, is to have children 
 with eyes well advanced in myopia brought for consulta- 
 tion by parents who have deferred the visit in the hope that 
 the longer they postponed the examination, the more chance 
 there will be of the apparent error of diminished distant 
 vision being outgrown. Errors of refraction are never out- 
 grown, but, on the contrary, if they are permitted to go 
 uncorrected, steadily increase, often insidiously, with re- 
 markable rapidity. 
 
 Parallel rays of light falling upon the cornea of a near- 
 
DEFECTS OR ANOMALIES OF REFRACTION 30 
 
 sighted eye are brought to a focus in front of the retina. 
 Myopia is corrected, therefore, by the superposition of a 
 concave lens before the eye, such lenses having the property 
 of causing the divergence of rays of light passing through 
 them, and the weakest concave glass which enables the 
 near-sighted eye to see sharpest is the measure of the degree 
 of myopia present (Fig. 19). 
 
 Other important factors, however, must be taken into 
 consideration before finally determining the lens which 
 shall be prescribed, for, as in hypermetropia, the selection 
 of the correcting glasses demands considerable skill and 
 judgment. Astigmatism may be present, and, as in hyper- 
 
 FiG. 19. — Correction of myopia by a concave lens. The eye is drawn of the natural size of a 
 myopic eye having an axial length of 27 mm. 
 
 metropia, there may be more or less associated spasm of the 
 cihary muscle, which may mask the true amount of myopia 
 present by adding to it, in consequence of the increased 
 thickness of the lens, and the earlier refraction of the rays 
 which is thereby occasioned. The necessity for the em- 
 ployment of a cycloplegic in the measurement of myopic 
 eyes is of even greater importance, therefore, than in test- 
 ing far-sighted eyes, for if too strong concave glasses are 
 prescribed, the ciliary muscle will be excited to still greater 
 action, and, thereby increasing the intra-ocular congestion 
 and softening the coats of the eye, cause actual increase in 
 the myopia. Atropine, therefore, should be the drug of 
 
40 HYGIENE OF THE EYE 
 
 choice in all tests of myopic eyes in childhood and adoles- 
 cence, the drug having the two-fold advantage of not only 
 enabling the examiner to determine with accuracy the de- 
 gree of myopia present, but also of putting the coats of the 
 eye at rest, of diminishing the congestion of the eye, and 
 allowing the eyeball to recover its natural vigor and tone. 
 Instead of " drops," so-called, being harmful, in this class 
 of cases they are, on the contrary, actually priceless, and 
 often check the progress of a rapidly increasing near- 
 sightedness. 
 
 As the tendency of myopia is to increase, examinations 
 should be made annually, until a period of comparative 
 non-progressiveness has been reached. After that, exami- 
 nations every two or three years are ordinarily sufficient. 
 
 While under certain conditions in older subjects cor- 
 recting glasses need be worn only to secure sharp distant 
 vision, in myopic children and adolescents it is imperative 
 that they be worn constantly, to remove all strain in near 
 as well as in distant use of the eyes. As must be apparent 
 from what has already been said about the progressive 
 nature of .myopia and the yielding tissues of the child's 
 eye, no prejudice about the wearing of glasses by children 
 for cosmetic or other reasons should be permitted to out- 
 weigh the great benefit to be derived from this most potent 
 and accurate manner of relieving ocular strain. After the 
 period of adolescence has passed and the danger of the 
 myopia increasing is lessened, it is oftentimes feasible, 
 provided the degree of the myopia is not too great, and 
 the coats of the eye healthy, to remove the glasses for con- 
 stant use and to resort to them only at close work, or at 
 such times at it may be desirable to obtain full distant 
 vision. Ordinarilv the same lenses mav be worn for both 
 
DEFECTS OR ANOMALIES OF REFRACTION 41 
 
 far and near use; in certain cases, however, it is desirable 
 to prescribe a weaker pair of lenses for close work. If the 
 near-sightedness is attended w^ith marked w^eakness of the 
 ocular muscles, prisms are often of value, and may be 
 ground into the concave lenses correcting the myopia. In 
 some cases, division of one or more of the eye muscles is 
 desirable. ]Myopia of very high degree is sometimes 
 lessened by the removal of the crystalline lens by operation. 
 This procedure, however, is not without danger, and is 
 only to be recommended in extreme cases. 
 
 As myopia increases with the use of the eyes, parents 
 and those engaged in the education of the j^oung should 
 realize the dangers of excessive reading and the prolonged 
 use of the eyes in all kinds of fine near work. In Chapter 
 VI detailed instruction regarding this and other phases of 
 the care of the eyes will be given in full, as well as an ac- 
 count of the method which has been suggested for the 
 education of high myopes. 
 
 As near-sighted individuals can at all times, unless 
 there be considerable astigmatism present, see near objects 
 clearly, they possess the advantage over those who are 
 emmetropic or hypermetropic of being able to read, etc., in 
 advanced life, after the presbyopic period has arrived, with- 
 out glasses. It is for this reason that the impression has 
 spread that near-sighted eyes grow stronger and vision im- 
 proves with age. This is not true, however, as the degi-ee of 
 true myopia never lessens, and proper concave glasses must 
 be worn at all times to obtain clear distant vision. 
 
 The so-called " second sight," or ability acquired by 
 some individuals to read late in life without the aid of 
 glasses, is really symptomatic of cataract, and is due to 
 swelling and increase in the refractive power of the lens, 
 
42 HYGIENE OF THE EYE 
 
 which is one of the stages of this form of ocular disease. 
 Astigmatism. — As has been defined elsewhere, astig- 
 matism is an error of refraction, dependent not upon 
 the shape of the entire eyeball, but upon an irregularity in 
 curvature in one of its refracting surfaces, usually the cor- 
 nea. If the curvatures of the two principal meridians of 
 the cornea are at right angles to one another, the astig- 
 matism present is said to be regular; irregular when the 
 unequal curvatures bear no definite relation to each other. 
 The latter form of astigmatism arises usually from injury 
 or disease of the cornea, which has affected its transparency 
 as well as its refracting curvatures. Irregularities in the 
 structure of the lens produce a slight amount of this form 
 of astigmatism in all eyes, which accounts for the irradia- 
 tion about the stars and for the rays of light which shoot 
 out from street lamps and other distant points of light. In 
 regular astigmatism, if the inequalities between the two 
 meridians of the cornea be but slight, vision may be but 
 little interfered with, but if the degree be at all marked, the 
 foci of the two sets of rays are so far apart that only a 
 blurred image of surrounding objects is obtained. Astig- 
 matism may be either hypermetropic or myopic, according 
 as one meridian is more or less curved than the other 
 meridian ; mixed when one meridian is myopic and the other 
 hypermetropic; or compound, when both have different 
 degrees of myopia or hypermetropia. A popular demon- 
 stration of astigmatism is to draw a line around an egg 
 through the ends and another around the middle, at right 
 angles to the first ; it will be evident that these lines have a 
 very different curvature, and that if the egg were made of 
 glass it could not form a sharp focus, as a glass sphere 
 does — it would be astigmatic. 
 
DEFECTS OR ANOMALIES OF REFRACTION 
 
 43 
 
 The symptoms evoked by astigmatism, in consequence 
 of the strain placed upon the ciliary muscle in its efforts 
 to focus the rays of different lengths, are usually very pro- 
 
 TiG. 20 A. — Figures on blackboard sharp and clear. This is the way they look to the child with 
 abnormal eyes after he has been properly fitted with glasses. 
 
 Fig. 20B. — Blurred picture of schoolroom, showing how room looks to a child with astig- 
 matic eyes. 
 
 nounced, and this form of ametropia may be suspected 
 when, in reading, the letters are confused and seem to run 
 together (Fig. 20), and when the head is inclined to one 
 
44 HYGIENE OF THE EYE 
 
 side in an eiFort to obtain sharper vision. The hds are 
 frequently contracted in an effort to shut out marginal 
 rays. Headache is common and other forms of reflex ner- 
 vous disturbances are present. If an astigmatic person 
 close one eye and gaze fixedly at a so-called astigmatic 
 dial (Fig. 21) placed 5 metres from the eyes, he will note 
 that certain rays appear much darker and more distinct 
 than others. This device often enables the ophthalmologist 
 to determine the axis of the corneal curvature, and is of 
 service in the final prescription for glasses. Astigmatic 
 persons usually attribute their poor vision to near-sighted- 
 ness. No form of spherical surface, be it convex or con- 
 
 FiG. 21. — Astigmatic dial. 
 
 cave, will, however, improve vision, for what is needed in 
 simple astigmatism is a glass which will correct one 
 meridian without affecting the other, and in compound or 
 mixed astigmatism, a glass with two curved surfaces, one 
 adapted to each meridian. A section of a C3dindrical glass 
 supplies the want. Fig. 22 represents such a glass; the 
 rays of light ab passing through its axis, meet with no 
 curve and are unrefracted, while those at right angles cd 
 meet with a strong convex surface and are brought to a 
 focus. Such cylindrical lenses are cut in the form ordinarily 
 used in glasses and placed in the direction corresponding 
 to the curvature of the astigmatism. They may also be 
 
DEFECTS OR ANOMALIES OF REFRACTION 45 
 
 incorporated with spherical lenses in the correction of cases 
 of compound astigmatism, i.e,^ astigmatism associated with 
 far- or near-sightedness. 
 
 The correction of astigmatism calls for the same care 
 as has already been outlined in the discussion of the treat- 
 ment of far- and near-sightedness. In subjects under 40 
 years of age, some form of cycloplegic is absolutely essen- 
 tial to determine the amount and axis of the astigmatism, 
 for the compensatory action of the ciliary muscle often ob- 
 scures the amount of the astigmatism and shifts its axis. 
 A faulty correction of astigmatism is almost as harmful as 
 no correction, and no glasses should be prescribed until the 
 
 
 d 
 
 
 l.----- 
 
 
 "="t^ 
 
 I_^_ 
 
 ■I 
 
 _TI_) 
 
 li _■ 
 
 -•-— ^ 
 
 T::i / 
 
 [/----- 
 
 / 
 
 r.-.-jr.--.-.-:^-—-.:: J 
 
 c 
 
 Fig. 22. — Cylindrical lens. 
 
 examiner has been satisfied, by several examinations in 
 which he has been aided by the various tests which have 
 been devised by ophthalmologists for the detection of this 
 error of refraction, that he has determined with absolute 
 accuracy both its amount and axis. 
 
 AxTiMETROPiA ; ANISOMETROPIA. — Thcsc tcrms are 
 used synonymously to define different degrees of refrac- 
 tion in the eyes of the same individual. Thus one eye may 
 be near-sighted and the other far-sighted or astigmatic, and 
 often considerable degrees of muscular imbalance accom- 
 pany the condition, with attendant difficulty in obtaining 
 comfortable simultaneous use of the two eyes. If one eye 
 is very near-sighted and the other almost of normal build, 
 
46 HYGIENE OF THE EYE 
 
 it is at times desirable not to attempt the correction of the 
 myopic eye, and refract one eye only. 
 
 Presbyopia. — ^When considering the subject of accom- 
 modation, presbyopia was defined as the loss in the power 
 of accommodation due to advancing years, and was found 
 to be dependent upon an increasing hardness in the crys- 
 talline lens. This hardening process is entirely physiologi- 
 cal and there is nothing abnormal for one who has previ- 
 ously suiFered from no ocular limitations whatsoever to be 
 compelled to resort to glasses to see small near objects 
 clearly at some time between the ages of 40 and 50 years. 
 The elongation of the eye by myopia and the added refrac- 
 tion strength acquired in this way may postpone the neces- 
 sity of the near-sighted wearing glasses to correct pres- 
 byopia until several years beyond the normal period, and if 
 the degree of the myopia be considerable, persons with this 
 error of refraction may be able to read the finest type with- 
 out glasses throughout life — a slight advantage to counter- 
 balance the limitations of far-sight always possessed by 
 myopes. On the other hand, hypermetropia, by the addi- 
 tional strain it entails upon the muscles of accommodation, 
 precipitates presbyopia. If, in the years preceding the 
 advent of the period at which presbyopia usually manifests 
 itself, the eyes have been of normal build and there is no 
 astigmatism present, the prescribing of lenses to improve 
 the perception of near objects is a simple matter and may 
 in many instances be left in safety to the optician and 
 optometrist, always with the recognition, however, that in 
 so doing the opportunity of submitting the eyes to a thor- 
 ough examination with a view to determining possible dis- 
 ease of the eyes or general system is not taken advantage 
 of, as would be the case were the test made at the hands of 
 
DEFECTS OR ANOMALIES OF REFRACTION 47 
 
 a competent medical adviser. If astigmatism or other as- 
 sociated anomaly of refraction is present, or imbalance of 
 the ocular muscles, the test becomes more complicated and 
 an expert examination is essential. Uncorrected pres- 
 byopia calls for a convex spherical glass for its correction, 
 thereby supplementing the refractive power lost by the 
 rigidity of the crystalline lens. The strength of the lens 
 must be increased every year or two, to supplement the 
 increasing hardness of the lens, until the age of 55 or 60 
 years has been reached, after which time no increase in the 
 lens strength for purely presbyopic purposes is necessary, 
 although later swelling in the lens from cataractous change, 
 or from certain structural changes in the eye, may neces- 
 sitate additional tests and other lenses. 
 
 Spectacles and Eye-glasses 
 Correcting glasses may be worn either in the form of 
 eye-glasses or spectacles. Monocles, or single eye-glasses, 
 so popular among the military and others of the upper 
 classes abroad, have fortunately never been popular in our 
 own country, as they throw undue strain upon the eye in 
 use and can only be regarded as a makeshift and never as 
 a lens capable of correcting a refraction error. 
 
 In the event that lenses must be worn constantly, spec- 
 tacles will under nearly all circumstances be found more 
 useful than eye-glasses. Cosmetically, however, the latter 
 are to be preferred, and unless there is some structural 
 peculiarity of the nose which prevents the proper adjust- 
 ment of eye-glasses, or unusually heavy lenses, or lenses 
 containing cjdinders for the correction of astigmatism of 
 such high degree that the slightest deviation in their axis 
 is attended with distress, adults may safely wear this form 
 
48 HYGIENE OF THE EYE 
 
 of adjustment. On account of the liability to displacement 
 and accident in play or romping, children should always be 
 fitted with spectacles and these should be provided with 
 stout rims for additional strength and to prevent injury to 
 the eye from the shattering of the lenses in case of accident. 
 
 The choice between spectacles and eye-glasses is, how- 
 ever, so far as adults are concerned, of but minor impor- 
 tance in comparison with the adjustment of the lenses be- 
 fore the eyes. The average person considers that the ocu- 
 list has finished his work when after the test he has been 
 given the formula and has obtained the glasses from the 
 optician. Every oculist, however, who is at all alive to 
 the welfare of his patients and his own reputation will 
 insist that he be given an opportunity to ascertain that the 
 lenses have been ground according to his prescription and 
 to see the lenses which he has prescribed in position before 
 the eyes. Many a carefully selected formula has failed to 
 give the relief expected by reason of a careless adjustment. 
 ]Vot only must the centres of the lenses correspond to the 
 ocular centres, but the distance of the lenses from the eyes 
 must be proper and no greater space permitted between 
 the two than is sufficient to prevent the tips of the eye- 
 lashes from touching the glass. 
 
 Lenses must be worn at a correct angle, i.e., somewhat 
 slanting, so that the top of the lenses is somewhat farther 
 away from the eyes than the lower portion. The accom- 
 panying photographs with their legends illustrate how 
 glasses should and should not be worn (Fig. 23). 
 
 When lenses of different strength must be worn for 
 far and near use, they may often be combined in bifocal 
 form ; that is to say, a reading segment may be fitted into a 
 space cut from the lower half of the distance lens to admit 
 
DEFECTS OR ANOMALIES OF REFRACTION 
 
 49 
 
 Fig. 23. — A, lenses too low and wide; B, lenses correctly positioned; C, lenses incorrectly 
 inclined; D, lenses correctly inclined; E, lenses out of horizontal alignment; F, lenses correctly 
 positioned. 
 
50 HYGIENE OF THE EYE 
 
 it. Recent optical improvements permit of the reading 
 glass being separately ground as an insert on the distance 
 lens, or cemented or fused to it. This latter is known as the 
 Kryptok lens, and the reading portion is invisible unless 
 examined under certain aspects. While a great conveni- 
 ence, especially to elderly people, in obviating a change of 
 glasses when adjusting the eye for various distances, many 
 have difficulty in accustoming themselves to them, espe- 
 cially in walking, on account of the blur thrown over ob- 
 jects directly in front of the feet. A precise adjustment of 
 the lenses, however, and some practice will usually over- 
 come this slight disadvantage. 
 
 As a substitute for the bifocal, so-called " fronts " are 
 sometimes prescribed, ix.^ the necessary strength of lens 
 for reading is mounted in a rigid eye-glass or spectacle 
 frame provided with hooks at each end, and slipped over 
 the distance correction at will. Ladies frequently have 
 lenses with proper reading strength mounted in a lorgnette, 
 which they hold superposed over their distance correction. 
 
 When glasses are worn for near use alone, the lenses 
 should be inclined forward and set about 5 mm. lower than 
 those for distance, to conform with the usual downward 
 fixation of the eye at close work. At times it is convenient 
 to cut away the upper half of the reading glasses, so that 
 the eyes obtain a clear view of distant objects over the top. 
 As few eyes are not benefitted by a correcting glass for 
 distance, the ordinary bifocal form is to be preferred. 
 
 Lenses should be amply large, though the present mode 
 of extraordinarily large glasses is not to be commended, 
 except for their employment in shooting, billiards, etc. 
 
 It is frequently of advantage to have the surface of the 
 lens curved instead of being flat, the advantage of these 
 
DEFECTS OR ANOMALIES OF REFRACTION 51 
 
 periscopic or toric lenses being that the curvature of the 
 glass approximately corresponds to the curve of rotation 
 of the movements of the eyeball, and the refraction is the 
 same through all parts of the lens, whereas in a flat lens, 
 and especially those of high power, the eye sees clearly 
 only through the optical centre of the lens, necessitating a 
 turning of the wearer's head in observing all side objects. 
 
 Wearers of glasses should make it a point to visit the 
 optician from whom they obtain their lenses at regular 
 intervals, in order to rectify any errors in adjustment. Such 
 service is usually rendered gratis and insures that the lenses 
 are properly centred. 
 
 In recent years the prescribing of colored or tinted 
 glasses has had quite a vogue, such lenses being ordered with 
 the idea of preventing certain harmful light rays from en- 
 tering the eye. There can be no question, however, but that 
 this has been overdone and that neither daylight nor ordi- 
 nary sources of artificial light contain radiations either in 
 kind or degree which are injurious to the healthy eye. The 
 comfort derived from amethyst, amber, and other tinted 
 glasses is usually psychic and is imparted largely by the 
 suggestion of the oculist or optician prescribing them. 
 While healthy eyes under ordinary conditions require no 
 interference with the rays coming from ordinary light 
 sources, diseased eyes do. Under such circumstances, those 
 of neutral shade, ix,, those known technically as London 
 Smoke, are to be preferred. Such lenses merely diminish 
 the amount of light entering the eye without interfering 
 with spectral or heat rays. The proper kinds of lenses to 
 protect the eyes from the deleterious action of an excessive 
 amount of light and heat rays has been discussed elsewhere. 
 
CHAPTER IV 
 STRABISMUS, CROSS-EYE OR SQUINT 
 
 If for any reason the harmonious action of the muscles 
 moving the eyes is disturbed, the normal parallelism of the 
 axes is interfered with and the eyes become crossed. This 
 may occur either as a result of paralysis of one or more of 
 the eye muscles from injury or serious systemic disease; it 
 may originate, as we have seen, from anomalies of refrac- 
 tion, or it may be congenital, and the eyes crossed from 
 birth. The character of the strabismus may be simple or 
 mixed. That is to say, an eye may turn in or out, in rela- 
 tion with its fellow, or this lateral deviation may be con- 
 joined with a vertical one, depending upon the number 
 of eye muscles affected. In paralytic squint, the deviation 
 as a rule occurs more or less suddenly and double vision 
 obtains. In strabismus from high degrees of farsighted- 
 ness or from myopia, the development of the deformity is 
 gradual and the perception of the image of the deviating 
 eye is suppressed, and double vision is absent. It is also 
 rarely present in congenital squint. 
 
 Squint or Cross-eye Resulting from Errors of 
 Refraction. — Under normal conditions, both eyes are di- 
 rected upon the same point at the same time. In regard- 
 ing near ob j ects, both eyes are strongly converged and held 
 in this position of focus largely through the action of the 
 internal rectus muscles, the two muscles chiefly concerned 
 in rotating the eyes inward. Simultaneously with this 
 strong convergent effort, to obtain a clear image of the 
 
 52 
 
STRABISMUS, CROSS-EYE OR SQUINT 
 
 53 
 
 object at which the eyes are directed, there must be a strong 
 contraction of the cihary muscle of each eye ( Fig. 24 ) . In 
 eyes of normal build, this action between convergence and 
 accommodation is equably adjusted and the balance is 
 maintained without strain, but in high degrees of far-sight- 
 edness, the harmonious action is disturbed by the super- 
 added amount of activity required by the ciliary muscles, 
 necessitated by the shortness of the globes. The centres in 
 
 Fig. 24. — Showing an increase in the angle of convergence of the optic axis in consequence 
 of an extreme rotation of one eye, L, inward. The angle i' is thus made larger than the angle 
 i, obtained for the eye, R, which consequently received a clearer image of vision, object A, 
 on its retina (Swanzy). 
 
 the brain controlling accommodative effort must send addi- 
 tional stimuli to the ciliary muscles, and the correlated 
 centres of convergence similar impulses to the convergence 
 muscles. In consequence the eyes are converged out of 
 proportion to the impulse needed for the distance upon 
 which they are focussed. Binocular vision is maintained 
 therefore only at the expense of great muscular strain and 
 is relinquished if any condition arises which increases the 
 difficulty or facilitates its interruption. Poor vision in one 
 
54 HYGIENE OF THE E^E 
 
 eye, either from astigmatism or disease, is an example of 
 the former contingency and the accidental discovery by 
 the subject that fixation with one eye while the other is 
 temporarily thrown out of focus relieves the strain, typifies 
 the latter. There are those who believe also that preter- 
 naturally weak brain centres controlling the muscles of the 
 eyes is also a controlling if not the chief factor in the causa- 
 tion of squint. 
 
 In consequence of the causes just related convergent 
 strabismus or cross-eye usually develops in hypermetropic 
 eyes at about the third year, at the age when near objects 
 are seriously regarded and the child holds the eyes in con- 
 vergence when playing with toys, or regarding picture 
 books, etc. The appearance of the squint soon after ill- 
 nesses of various kinds frequently occasions the assump- 
 tion that the particular disease from which the child has 
 suffered has determined the ocular deviation. This idea, 
 however, is erroneous, such illnesses precipitating the squint 
 only in so far as they occasion a lowering of the general 
 vitality and weaken the tone of the ocular muscles and the 
 centres which supply them. 
 
 The correction of convergent squint consists in the es- 
 tablishment of a normal relationship between convergence 
 and accommodation. This is accomplished by the adjust- 
 ment of spectacles containing convex spherical lenses of 
 sufficient strength to correct the amount of far-sightedness 
 present. If this be done shortly after the squint has mani- 
 fested itself, its correction is immediate and the eyes are 
 straight as long as the glasses are worn. If there be delay 
 and the lenses are prescribed some months or years after 
 the strabismus has appeared, the squint may still persist, 
 and the cure of the condition by glasses alone be impossible. 
 
STRABISMUS, CROSS-EYE OR SQUINT 55 
 
 The reason for this is two-fold. In the first place, in con- 
 sequence of the long suppression of the mental images re- 
 ceived from the squinting eye, a happy device of nature to 
 avoid the double vision which would naturally follow the 
 departure from parallelism of the visual axes, the vision 
 in the squinting eye becomes progressively impaired, and 
 even though the refraction error be corrected by proper 
 glasses, the eye will not cooperate with its fellow unless 
 something is done to break up the habit of non-participa- 
 tion which it has acquired through disuse. Again, various 
 contractions of the muscles occur, in consequence of faulty 
 action, which prevent their properly cooperating with the 
 muscles of the other eye, even after the normal bal- 
 ance between convergence and accommodation has been 
 restored. 
 
 Squint, therefore, not only disfigures, but actually dis- 
 ables, impairing the vision of the crossed eye. Too much 
 emphasis cannot be laid, therefore, upon the importance of 
 correcting squint early. There is an impression, confined 
 not merely to the laity but shared also by many general 
 practitioners as well, that squint is often outgrown and 
 that it is well to wait until the child suffering with squint 
 is more matured before its correction is attempted. While 
 this is sometimes true of the purposeless movements which 
 are observed in the eyes during the first year of life, any 
 constant deviation which persists after this age should 
 awaken suspicion and should lead to the consultation of a 
 competent oculist. While it may seem an unnecessary dis- 
 figurement to adjust spectacles to the eyes of a child two 
 or three years of age, such action not only may insure 
 straight eyes for life, but, what perhaps is more essential, 
 may prevent the loss of sight in the deviating eye. 
 
56 HYGIENE OF THE EYE 
 
 In some cases, glasses need not be given at such an 
 early age, but the knowledge possessed by eye specialists 
 should be spread wide that if efforts are not made to cor- 
 rect such eyes and develop the vision in the squinting eye 
 before 6 years of age, but little can be done to restore sight 
 in the deviating eye, even though the eyes be straightened 
 by glasses or operative procedures. Ophthalmologists have 
 at their command various instruments, based upon stereo- 
 scopic principles, to develop vision in this class of cases, 
 which are often of great service, in conjunction with the 
 correction of the refraction errors, in reestablishing 
 parallelism of the visual axes. 
 
 While in far-sightedness there is an associated excess 
 of convergence, in near-sightedness there is a deficiency, the 
 near-sighted eye, in consequence of its adaption for the 
 perception of near objects, being enabled to regard these 
 without the accommodative effort necessary to a normal 
 eye. Too slight associated impulses, therefore, are sent to 
 the converging centres, and near-sighted eyes show a 
 strong predilection to deviate outwards, to become what is 
 popularly known as " wall-eyed." Fortunately, in diver- 
 gent squint, there is not the same tendency to suppression of 
 the visual image as has been noted in the convergent variety, 
 for the eyes, though failing to* converge in harmony, main- 
 tain their vision independent of one another. The early 
 prescribing of the proper concave spherical lenses is indi- 
 cated in this class of cases, conjoined with the building up 
 of the adducting strength of the weakened muscles by 
 proper exercises with prisms, etc. 
 
 Congenital Squint. — Not all cases of squint are de- 
 pendent upon errors of refraction, for in many instances 
 the strabismus is present at birth. In this type of strabis- 
 
STRABISMUS, CROSS-EYE OR SQUINT 57 
 
 mus, the muscles themselves are usually at fault, being 
 faultily inserted into the globe, or, as sometimes happens, 
 absent altogether. The degree of squint may vary in such 
 cases from a slight deviation which is only manifest in cer- 
 tain excursions of the eyes, to an extreme deformity. As 
 in divergent squint, vision may not be compromised, as 
 both eyes frequently participate in binocular vision in some 
 parts of the field of fixation. The need of early correction 
 is not so pressing, therefore, as in convergent squint. 
 Xevertheless, prompt detection of this variety of squint is 
 of great importance, in order that proper measures may be 
 instituted to insure parallelism of the visual axes as soon as 
 possible. 
 
 Slight deviations, as in other varieties of insufficiencies 
 of the muscles, may be corrected by means of prisms. 
 
 To gain parallelism of the visual axes, however, and to 
 insure the participation of both eyes in all their excursions, 
 some form of operative treatment is usually necessary. As 
 in the treatment of the other varieties of squint, the oper- 
 ator has the choice of either weakening the muscles that are 
 too strong by tenotomy, an operation which consists in par- 
 tially or wholly loosening the tendinous attachment of the 
 muscle into the globe, or of strengthening the weak muscles 
 by a shortening process. These latter procedures are desig- 
 nated as advancements, and consist either in shortening the 
 muscle by a process of " tucking " or of dividing the muscle 
 from its old attachment and sewing it forward into a new 
 position on the globe. Tenotomy is a simple procedure, 
 advancement an operation of some magnitude. Both re- 
 quire experience and skill for their successful accomplish- 
 ment. Tenotomies may be safely performed at an earlier 
 
58 HYGIENE OF THE EYE 
 
 age ; generally, however, it is safer to wait until the ninth 
 or tenth year of age before attempting advancements. 
 
 As a rule, blind eyes tend to diverge, and it is generally 
 useless to attempt to obtain parallelism in such cases by 
 any form of operative procedure, for without the stimulus 
 of vision to hold the eyes in fixation, such operations are 
 usually futile, the deviations recurring after the primary 
 effect of the readjustment of the muscles has passed. 
 
CHAPTER V 
 
 THE INFLUENCE OF OPTICAL DEFECTS 
 UPON THE GENERAL SYSTEM 
 
 It may readily be gathered from the perusal of the 
 previous two chapters that any decided derangement in 
 the build of the eyes or in the proper balance of the ocular 
 muscles may, under certain conditions, exert a profound 
 influence upon the general system, and the daily experience 
 of all specialists in eye diseases supports this supposition. 
 
 Such phenomena are usually of reflex origin, and have 
 their manifestation in organs which have some association 
 with the eyes, by virtue of connections both near and 
 remote, through the central nervous system. It is rare that 
 these reflex symptoms arise in others than eye workers, 
 who employ many hours daily in the close use of the eyes. 
 At times, however, they are encountered in individuals who 
 lead for the most part an outdoor life, with a minimum 
 amount of eye-strain. 
 
 When it is remembered that the eye may be regarded 
 as an end organ of the brain and that of the 12 pairs of 
 cranial nerves 6 have some connection with the eye, and 
 that several of these have relationship with nerves supply- 
 ing other important organs of the body, it is not surprising 
 that ocular anomalies entail more or less derangement 
 in the functions of these organs. The degree of impres- 
 sionability of the nervous system in each individual has 
 much to do with the appearance of such reflexes, and errors 
 of refraction which would occasion no reflexes whatever in 
 unresponsive individuals will, in a person of nervous dis- 
 
 59 
 
60 HYGIENE OF THE EYE 
 
 position, originate disturbances in the functions of the 
 body of considerable moment. An examination of the eyes 
 of such cases usually reveals an error of some magnitude. 
 Probably the most common symptom caused by eye 
 strain is headache. Indeed, it has been estimated that 71.3 
 per cent, of cases who consult oculists suffer from some 
 form of head pain. The pain from eye-strain may occur 
 in any part of and all through the head, so that from its 
 location alone it is impossible to differentiate headache 
 from eye-strain from that due to other causes. Usually, 
 however, pain over both or one eye is significant, but dull 
 pain in the back of the head is scarcely less so, and pain in 
 the temples and top of the head is frequently originated by 
 eye-strain. The time of the occurrence of the head pain 
 may, however, often establish a causal connection between 
 it and eye-strain. Thus, it will be ascertained that a morn- 
 ing headache was induced by the prolonged use of the eyes 
 the night previous. In another patient, headache will ap- 
 pear in the late afternoon, after an all day's labor at the 
 desk, whereas on Sundays or holidays there is perfect free- 
 dom from all such symptoms. It must be noted, though, 
 in this connection, that headache may be just as likely in- 
 duced by the strain of regarding distant as well as near 
 objects. In fact, in many defects of the ocular muscles, 
 distant fixation is more apt to give rise to distress than 
 prolonged application at close range. In this class of in- 
 dividuals, headache will appear in the morning after a 
 night spent at the theatre or at a lecture, or will be occa- 
 sioned by watching moving objects, as in crowds, or pass- 
 ing objects when seated in a trolley or railroad car. If 
 the patient be catechised sufficiently, a connection between 
 some unusual near or distant use of the eyes may generally 
 
INFLUENCE OF OPTICAL DEFECTS ON SYSTEM 61 
 
 be ascertained, and the clew given which will lead to the 
 recognition of the cause of the trouble. 
 
 A large proportion of the sub j ects who suffer from eye- 
 strain present no associated ocular symptoms whatsoever. 
 Indeed, it may be put down as a rule that eyes with red 
 lids and other signs of congestion do not, as a rule, cause 
 headache or other reflexes. The strain seems to be relieved 
 by the local turgescence, and head symptoms are absent. 
 Although the eyes themselves present nothing abnormal 
 to the casual observer, it is often possible to elicit data 
 which are at least suggestive that they are at fault. Thus, 
 many subjects will complain of the print blurring after 
 prolonged reading, of restricted distant vision, of occa- 
 sional double vision, in fine of those symptoms usually de- 
 scribed under the term of astlienopia. 
 
 In many instances, however, there is nothing which 
 serves to attract the attention of the sufferer to any ocular 
 deficiency whatsoever, and the headaches are variously as- 
 cribed by him to biliousness, hunger,. brain fag, and a variety 
 of other causes. Others count themselves victims of an in- 
 herited trait and resign themselves to a life of suffering. 
 Despite the claims of some that migraine or sick headache, 
 that distressing form of recurring head pain, with asso- 
 ciated sick stomach and vomiting, and often accompanied 
 by various forms of visual phenomena, i.e., the perception 
 of flashes of lights, motes, etc. {vide p. 189) is invariably 
 caused by eye-strain, experience teaches that while it is 
 true that such attacks may sometimes be cured, they are 
 more often only controlled, and oftener still entirely unin- 
 fluenced by ophthalmic treatment. While migraine may in 
 many instances be viewed as but a peculiar variety of 
 headache and having but little relationship with the gen- 
 
62 HYGIENE OF THE EYE 
 
 eral health, it may be symptomatic of serious disease within 
 the brain, and its occurrence should always lead to a care- 
 ful medical examination, with a view to determining its 
 true nature. 
 
 Not only may headache be induced by eye-strain, but 
 other reflexes may also be occasioned by it, which mani- 
 fest themselves in digestive disturbances. These may vary 
 from flatulency, faulty digestion and its product constipa- 
 tion, to nausea and actual vomiting. The accompanying 
 schematic anatomical explanation (Fig. 25) demonstrates 
 the connection of the nerves of the eye with those of the 
 stomach and illustrates how such symptoms may arise. In 
 consequence of ocular anomalies and the resultant strain, 
 nerve energy that should have been expended elsewhere is 
 diverted to the eyes, and the functions of the organs robbed 
 of their proper stimulus suffer. The history of such cases 
 is as follows : A patient who is accustomed to use his eyes 
 much at short range suffers from indigestion almost con- 
 stantly as long as he carries on his work. He interrupts 
 his labors for a short holiday in the open air, away from 
 his books, and his digestive symptoms vanish. He eats 
 everything without difficulty. He returns to his desk and 
 in a few days distress reappears. The ocular cause of his 
 symptoms being unsuspected, his diet is looked into and 
 certain articles of food denied him. He is enjoined to 
 spend more time in the open air, and riding or golf is pre- 
 scribed. By dint of this, of daily exercise and great cau- 
 tion with his diet, his work is continued with more or less 
 discomfort and restriction. Finally some one calls his 
 attention to his eyes and he is properly glassed, and very 
 shortly, to his amazement and gratification, he finds that 
 his liver no longer gets out of order and that he can take 
 
INFLUENCE OF OPTICAL DEFECTS ON SYSTEM 63 
 
 Ophthalmic ganglion 
 Carotid plexus 
 Infraorbital 
 
 Second division 
 fifth nerve 
 
 First division fifth nerve 
 
 , First division third nerre 
 First division fifth nerve 
 
 Nucleus third nerve 
 
 Nucleus fifth nerve 
 
 Meckel's ganglion 
 
 Superior cervical 
 ganglion 
 
 Ganglion of the 
 
 root 
 Medulla of pneumogaa- 
 
 trie nerve 
 First cervical nerve 
 Second cervical nerve 
 
 Middle cervical ganglion 
 
 Inferior cervical ganglion 
 
 Pneumogastric nerve 
 
 Stomach 
 
 -7. / 
 
 th'p Pvrr;^,w?^"l^*'^ diagram of the cerebrospinal and sympathetic nerve connections between 
 ine eye and the stomach. fHnnsplI Pn^^^r «r,ri Kr.;ii„^ ">ri,„ ir.,^ „^^ *i,„ m^_„^.,„ <,.„* -m 
 
 stomach. (Hansell, Posey and Spiller, "The Eye and the Nervous .Syste 
 
 m.") 
 
64 HYGIENE OF THE EYE 
 
 decided liberties with his diet without fear of evil con- 
 sequences. 
 
 The reader must not deduce from this that ocular dis- 
 orders are responsible for all forms of faulty digestion; 
 that ocular imbalance does, however, play an important 
 contributing factor in many such cases is attested by the 
 experience of many clinicians and ophthalmologists. 
 
 Vertigo. — Vertigo, head swimming, or dizziness, may 
 be due to a variety of causes. Heart disease is perhaps 
 chiefly responsible for the majority of the cases, but any 
 other condition of the system which temporarily or per- 
 manently affects the equilibrium may operate as a causal 
 factor. Ocular vertigo may be occasioned by errors of 
 refraction or faulty action of the ocular muscles, and is 
 usually excited by the use of the eyes at near work. Where, 
 however, it is dependent upon some gross anomaly in the 
 functioning of the muscles, it may be present constantly, 
 and only relieved by closing the eyes. Under such cir- 
 cumstances, vertigo is usually associated with double vision 
 and the diagnosis of the ocular source of the dizziness 
 patent. 
 
 In other instances, however, cases in which the ocular 
 error is but slight, the most searching test is often neces- 
 sary to determine the seat of the trouble. The author has 
 in mind a man of massive build and robust health, an im- 
 portant personage in civic life, who was about to resign his 
 position of responsibility on account of a troublesome 
 vertigo which had been unrelieved by medical treatment, 
 and who was entirely cured of the dizziness by the super- 
 position of a weak vertical prism into his glasses. Ordi- 
 narily vertigo, when dependent upon minor ocular defects, 
 occurs in those who are run down, or whose eyes are weak- 
 
INFLUENCE OF OPTICAL DEFECTS ON SYSTEM 65 
 
 ened from excessive near use. Nausea and vomiting may 
 be attendant phenomena. The treatment of ocular vertigo 
 may usually be accomplished by the adjustment of proper 
 glasses, or by operation upon the eye muscles, and the cure 
 which is usually effected earns the lasting gratitude of the 
 patient. 
 
 Car sickness is often dependent upon the same causes 
 as ocular vertigo and may be entirely relieved in many in- 
 stances by ocular treatment. 
 
 Chorea or St. Vitus" Dance. — The frequently re- 
 peated blinking of the lids, associated at times with twitch- 
 ing in the muscles of the face, is often dependent upon 
 eye-strain, and, as in the other affections just described as 
 of reflex ocular origin, may be seen in association with ap- 
 parently insignificant ocular errors, the intensity of the 
 reflex phenomena excited by the eye-strain being less de- 
 pendent upon the degree of the anomaly present than upon 
 the impressionability of the nervous system of the indi- 
 vidual afl*ected. 
 
 The chorea of eye-strain must, however, be differen- 
 tiated from true chorea, which is probably infectious in 
 nature, with superadded psychical phenomena. Ocular 
 or habit chorea usually occurs in children whose eyes are 
 not alone at fault but whose nervous system is not equal to 
 the strain of school life. A cessation of school work, tonics, 
 and the like, are of service, but study cannot be resumed 
 without a return of the grimaces, unless the correction of 
 the ocular defect has been made. 
 
 By removing the strain upon the nerve centres and 
 thereby lessening their sensibility to peripheral impulses, it 
 has been found in many instances that a painstaking cor- 
 rection of any ocular error will often lessen, if not cure, 
 
6Q HYGIENE OF THE EYE 
 
 the habit of wetting the bed, common with some children 
 long past infancy. 
 
 Faulty Position and Spasmodic Movements or the 
 Head Due to Eye-strain. — In order that the body may 
 properly perform its functions and all the organs act in 
 harmony, a certain reciprocity must be maintained between 
 the different parts. Nowhere is this reciprocity, this asso- 
 ciation of action, better observed than in the movements of 
 the head and eyes. On account of the protected position 
 of the eyes and the direction of the plane of the orbit in the 
 human skull, the field of sight is restricted much more in 
 man than in some of the lower animals whose eyes are much 
 more mobile, and were it not for the increase in the range 
 of the field of sight which the rotation of the head affords, 
 man would be unable to perceive many side objects without 
 change of position of the entire body. Not only does the 
 head, however, by its movements augment the range of the 
 field of vision, but it also supplements the action of the 
 extra-ocular muscles in the delicate task of maintaining 
 proper visual axes. To properly perform this two-fold 
 task, the head is provided with numerous and intricately 
 acting muscles, and it is only when one remembers that there 
 is scarcely a position assumed by either the eyes or head in 
 which the action of both parts do not enter, that we realize 
 how intimate the relationship between the muscles of the 
 eye and those of the neck is ; indeed, it might be added the 
 musculature of the entire body as well, for it is usual for the 
 muscles of the trunk to be implicated in a greater or less 
 degree in all vicarious positions of the head. 
 
 The accompanying illustrations (Fig. 26) depict faulty 
 positions of the head assumed by individuals with paralysis 
 of eye muscles, in consequence of a compensatory effort to 
 
INFLUENCE OF OPTICAL DEFECTS ON SYSTEM 67 
 
HYGIENE OF THE EYE 
 
 avoid the double vision and ocular vertigo occasioned by the 
 palsy, the head being turned in the direction of the affected 
 muscle, thereby supplementing its action, so that for every 
 
 Fig. 27. — A, depicts the expression sometimes indicative of an overaction of the muscles 
 puUinfe- the eyes in. B, weakness in the same group of muscles (Stevens, "Motor Apparatus 
 of Eye." Courtesy, F. A. Davis Co.) 
 
 Fig. 28. — Shows the compressed brow on one side and the elevated one on the other, 
 sometimes observable when the eyes are not on the same horizontal plane, i.e., one eye looks 
 higher than the other. (Stevens. Courtesy, F. A. Davis Co.) 
 
INFLUENCE OF OPTICAL DEFECTS ON SYSTEM 69 
 
 variety of palsy there is a characteristic pose of the head. 
 Similar deviations, though to a less extent, are observed in 
 cases of latent trouble in the ocular muscles, and often are 
 the means of calling the attention of the oculist to the faulty 
 muscles. 
 
 Associated with the tilting of the head, and in minor 
 degrees of anomalies of the ocular muscles, occurring 
 without any change in the position of the head, various 
 
 Fig. 29.— Showing torticollis from vertical deviation of one eye. 
 
 contractions occur in the muscles of the face, which find 
 expression in the appearance of grooves and wrinkles, which 
 at times entirely change the expression. The illustrations 
 adjoining (Figs. 27 and 28) express the views of a well- 
 known American oculist, who asserts that it is possible by a 
 study of such changes in the lineaments to determine the 
 particular muscles which occasion theme 
 
 A condition of wry-neck which occurred in the prac- 
 
70 HYGIENE OF THE EYE 
 
 tice of the author is illustrated by Fig. 29, the spasm in 
 one of the principal muscles of the neck having been occa- 
 sioned in consequence of an extreme tilting of the head, 
 by the patient's effort to overcome the disturbance in vision 
 following a paralysis of one of the muscles which elevates 
 the eye. 
 
 Another type of cases in this group is the occurrence of 
 head jerking in association with oscillations of the eyeballs 
 in you7ig children. In this disease the child moves its head 
 rapidly, either from side to side or up and down, or at 
 times with associated horizontal and vertical movements, 
 while the eyes make rapid to and fro movements. This 
 condition usually arises in children with rickets and other 
 nutritional disturbances, in consequence of which the 
 centres in the brain controlling the movements of head and 
 eyes become impoverished at the time the child is learning to 
 coordinate the movements of the eyes with those of the 
 head; an initial eye lesion occurring, compensatory head 
 movements appear. 
 
 Oscillations of the eyeball {nystagmus) , either to and 
 fro, rotary, or up and down, or combinations of one or all 
 such movements, are sometimes observed. They occur for 
 the most part in individuals with poor vision, are usually 
 involuntary, and generally provoked by efforts to see ob- 
 jects clearly. Heredity is a factor in some cases, the 
 anomalous movements in the eyeballs being transmitted 
 from generation to generation. 
 
 Oscillations of the eyeballs may also arise in individuals 
 whose work demands the direction of the eyes in abnormal 
 and strained attitudes. Probably from an effort to steady 
 the movements of the eyes and to transfer the strain from 
 the most affected group of eye muscles, the head is often 
 
INFLUENCE OF OPTICAL DEFECTS ON SYSTEM 71 
 
 held in peculiar positions and at times develops a slight 
 tremor. The most striking instance of this acquired form 
 of eye movements is that observed in miners — ^the so-called 
 miner s nystagmus, the faulty movements of the eyes origi- 
 nating in consequence of the unnatural position assumed by 
 the miners in the shafts as they strike with their picks at 
 the coal in the vein above their head. The insufficient illu- 
 mination under which the work is carried on is also a con- 
 tributing factor, nystagmus arising much less often in well- 
 lighted mines. An entire cure is effected by the abandon- 
 ment of mining, by prolonged rest to the eyes, and by the 
 correction of any ocular deficiencies. 
 
 Epilepsy. — This serious disease of the nervous system, 
 with its associated attacks or convulsions and interference 
 with the health of the brain, has important ocular symp- 
 toms. The warnings, or " aurse," so called, which fre- 
 quently make the subject of this disease aware of an 
 approaching attack, are not infrequently connected with 
 the eyes, and the patient's attention excited either by a 
 sensation of muscle strain or double vision or by the appear- 
 ance of some variety of visual perception {vide page 183) . 
 
 By reason of the association of these eye symptoms with 
 epilepsy, some have gone so far as to claim that eye-strain 
 may actually originate the disorder, and that it needs but 
 the careful correction of the eyes with proper lenses to ef- 
 fect a cure. From the author's experience in the treatment 
 of a considerable number of such cases, in the State Hos- 
 pital for the Insane at Xorristown, and in the Pennsyl- 
 vania Hospital for Epileptics, it would appear, however, 
 that while the ophthalmologist can relieve and diminish 
 the number of seizures in certain cases in which the dis- 
 ease has been of not too long standing, and who present 
 
72 HYGIENE OF THE EYE 
 
 some form of visual aura or subjective sign of eye-strain, 
 he cannot cure epilepsy. It would seem proper, therefore, 
 in view of the facts just cited, that every case of epilepsy 
 which has not progressed into the last stages should have 
 the benefit of a searching ophthalmological examination 
 and a careful correction of the eyes with glasses or by 
 operation upon the eye muscles where such is indicated. 
 The cure of most forms of epilepsy has not yet been dis- 
 covered, but our knowledge of this complex disease con- 
 vinces that the ocular phenomena observed in connection 
 with it are merely symptomatic and associated, and by no 
 means essentially causal. 
 
CHAPTER VI 
 
 SCHOOL LIFE; ALSO SOME HINTS REGARDING 
 THE CARE OF EYES IN GENERAL 
 
 Undee this caption may be considered the various 
 phases of the answer to the question, " How shall I best 
 care for my eyes, that I may conserve vision and keep my 
 eyes in a healthy and useful state as long as I live? " It 
 will be shown in later chapters that the eyes are healthy 
 only so long as the body is healthy, and that ill-health is 
 always deleterious to the organs of sight. It may be well, 
 however, in this connection to emphasize the particular 
 evil of bad health in childhood upon the eyes and to warn 
 against their overuse in early life during illnesses or con- 
 valescence from them. Attacks of measles and other fevers 
 should be followed by long periods during which the eyes 
 are used but little at close work, for if this precaution is 
 not followed, near-sightedness and astigmatism will likely 
 develop in consequence of the softening and congestion 
 of the ocular tissues which so often accompany these 
 conditions. 
 
 Many hours daily shovild be spent in the open air to 
 tone up the bodily vigor and to rest the eyes in the parallel- 
 ism of the visual axes associated with regarding distant 
 objects. 
 
 From early childhood the eyes should be carefully 
 cleansed of mucus and the lashes freed from all tenacious 
 particles of conjunctival secretion by morning and even- 
 ing bathing with a warmed saturated solution of boracic 
 
 73 
 
74 HYGIENE OF THE EYE 
 
 acid. Reading or studying in the morning before break- 
 fast, or at least before nourishment of some kind, should 
 be discouraged. 
 
 The books and magazines read earliest should have 
 large lettering and striking pictures and all puzzles and 
 games should be prohibited which have small figures or 
 dazzling combinations of form or color. Many devices 
 in common use in kindergarten instruction are harmful, 
 owing to the concentration of vision which they necessitate, 
 and teachers and parents would do well to choose only those 
 which are free from these objections. While modern archi- 
 tecture and the movement to insure proper housing have 
 done much, by proper window-spacing, to insure sufficient 
 daylight in dwellings, many houses, especially in city 
 streets, receive insufficient light from the sun. Under such 
 conditions, desks and playthings must be brought nearer 
 the windows, and the children routed out of dark corners. 
 Children should be taught from the earliest age never to 
 gaze long upon any near objects brightly illmninated 
 by the direct rays of the sun. Exception must be taken 
 also to the harmful practice of riding babies in coaches 
 while they are lying flat on their backs with the full glare 
 of the sun falling upon their faces. All such coaches 
 should be provided with tops and lined with some green 
 material. 
 
 As insisted upon in another chapter, children should 
 be protected from all toys and articles with sharp edges or 
 points which can possibly injure the eyes. 
 
 In the chapter dealing with proper artificial lighting, 
 valuable information is given regarding this essential to the 
 conservation of good eyesight, but it may be emphasized in 
 this connection that what is necessary for the eyes of adults 
 
SCHOOL LIFE AND CARE OF EYES 75 
 
 is doubly so for the eyes of children, and that under no cir- 
 cumstances should children be permitted to use their eyes 
 except under the best lighting conditions possible. When 
 twilight supervenes, artificial lights should go on, unless 
 the wise parent utilizes this witching hour to rest the eyes 
 of the young by such tales and anecdotes as will serve t:) 
 amuse and instruct. Xo reading should be permitted by 
 the flickering light of the open fire. 
 
 School Life. — Unless under exceptional circum- 
 stance of domestic utility or necessity, children should 
 rarely be permitted to start school life until they have 
 passed their sixth birthday. Few are sufficiently devel- 
 oped or sturdy enough to properly endure either mentally 
 or physically the discipline and exactions of application 
 and study before that age. A^Hien there can be no home 
 training, kindergartens are useful, but usually some sup- 
 plementary form of home instruction may be instituted 
 in earlier years, which will serve to prepare the child for 
 understanding and appreciation of the first year of real 
 school life. 
 
 Examination of Eyes. — Before entering upon the 
 duties of school life, it is essential that parents and edu- 
 cators should have a definite knowledge of the visual con- 
 dition of each child, and no child should be permitted to 
 commence his studies until he has been subjected to a 
 careful ocular examination. When possible, this should be 
 made by a trained oculist and all disqualifying defects cor- 
 rected by proper glasses. In the examination of the very 
 large number of children in the public schools of the large 
 cities, however, such expert supervision is not always feasi- 
 ble, and the visual tests are often necessarily performed 
 by teachers or general medical practitioners, reference 
 
76 HYGIENE OF THE EYE 
 
 being made to the trained specialist of such cases which 
 manifest some considerable defect. 
 
 Such tests are of paramount importance not only for 
 the parent, who becomes acquainted for the first time with 
 the existence of defects which may cause a relinquishing 
 of plans for the future career of his child, but also for the 
 child, as the correction of detected errors of refraction en- 
 ables him to enter upon school life upon equal terms with 
 his fellows with normal eyes, which would not have been 
 the case had his visual deficiency not been recognized. In 
 years past, too many scholars have suffered from head- 
 aches or have been adjudged stupid and backward and 
 punished accordingly, by reason of defective vision alone. 
 As will appear presently, special classes and individual 
 forms of instruction have been devised for those with very 
 poor vision, so that a thorough comprehension of the visual 
 status has become of prime importance to all concerned in 
 education. 
 
 School life begun, the educators in charge should see 
 that the periods of instruction are not too prolonged (for 
 beginners half -hour lessons are amply long) , and that each 
 period be followed by a short recess, which should never be 
 forfeited as a punishment for bad behavior. These periods 
 of relaxation will give the eyes opportunity to glance at 
 objects at long range, and will permit of a change of air 
 and scene. In the higher classes, the best authorities agree 
 that lessons should not last more than 45 minutes, and 
 that each should be followed by a recess of at least 15 
 minutes. In arranging the order of subjects for study 
 care should be given that two periods in which the 
 pupils use their eyes at near range should not follow 
 each other. 
 
SCHOOL LIFE AND CARE OF EYES 
 
 77 
 
 The three great requisites necessary in all school rooms 
 are the following: adequate lighting, proper seating facili- 
 ties, and suitable books. 
 
 Fig. 30. — MoQlthrop movable and adjustable school chair, Model B, manufactured by 
 Lanffslow, Fowler Co. 
 
 The first of these has received full consideration in a 
 special chapter. Regarding the second, the general rule 
 should ohtain that in reading, the distance of the eves from 
 
78 HYGIENE OF THE EYE 
 
 the book should be as great as the height of the child per- 
 mits. Children have a tendency to lessen the distance, both 
 from the unconscious desire to obtain the larger image of 
 the object which is thrown upon the retina when viewed at 
 close range, as well as from the increased muscular fatigue 
 
 Fig. 31. — The " Princeton " adjustable desk and chair, manufactured by the New Jersey 
 
 School Furniture Co. 
 
 consequent upon maintaining an upright posture, but this 
 practice should be combated, as it increases eye-strain and 
 favors the development of spinal curvature. 
 
 To secure proper postural conditions, all desks should 
 be made of adjustable parts, so that they may be fitted to 
 the varied heights of the pupils. The tops of desks should 
 be slanted, so that they make an angle of approximately 
 
SCHOOL LIFE AND CAEE OF EYES 79 
 
 45° with the floor line. A distance of from 14" to 16" 
 should be maintained at all times between the eyes of the 
 pupil and the book under examination on the desk. A 
 popular model and one which has been endorsed by 
 Madame Montessori is shown in Fig. 30. 
 
 Fig. 32. — Adjustable desk and chair, manufactured by the American Seating Co. 
 
 The desk is provided with a sliding desk top, which 
 can be pushed aside at will, to permit of the pupil's readily 
 rising and maintaining an upright posture, a restful change 
 after a long period of sitting. Other admirable desks are 
 shown in Figs. 31, 32, 33, and 34. 
 
 Burgenstein, in his excellent book on " School Hy- 
 
80 
 
 HYGIENE OF THE EYE 
 
 giene," recommends half -yearly measuring of the school 
 population and allotment of seats according to the results 
 found. He has devised a measuring rod useful for this 
 purpose with devices marked upon it corresponding to the 
 various sizes of desk. Faulty postures assumed at im- 
 properly adjusted desks are responsible for much evil, for 
 
 Fia. 33. 
 
 Fig. 34. 
 
 Figs. 33 and 34. — Adjustable racks designed by the Paatural League Society. 
 
 not only may visual disorders arise in consequence of too 
 httle distance between the eyes and the desk, but various 
 spmal curvatures may be induced which may seriously im- 
 pair health throughout life. The accompanying illustra- 
 tion (Fig. 35) gives a graphic demonstration of one of 
 these conditions. 
 
 To relieve the eyes of the very young from the strain of 
 
SCHOOL LITE AND CARE OF EYES 
 
 81 
 
 close work, it has been suggested that in the first two years 
 of school life all writing should be upon the blackboard in- 
 stead of upon paper. As the slate and paper blackboards 
 which are commonly in use after a time become gray from 
 chalk dust, so that figures and letters done in white chalk 
 are not always legible, it has been proposed to substitute 
 
 Fio. 35. — Distortion of the trunk while working at a too high desk. 
 
 mural tablets of black glass, which have the advantage of 
 being exceedingly durable, of preserving a perfect writing 
 surface, and of being readily cleaned by an ordinary damp- 
 ened sponge or rubber. Instead of black glass boards, 
 upon which white chalk is used, dark green boards 
 have been introduced into a number of schools and yel- 
 low crayons used for contrast. With this exception, it 
 is generally accepted that colored crayons should be 
 
82 HYGIENE OF THE EYE 
 
 used only in artistic instruction, or for such purposes as 
 map drawing. 
 
 All blackboard work should be in large writing and the 
 boards so placed that they receive sufficient illumination. 
 They should never be so highly polished that reflected light 
 from them dazzles. Large shiny blackboards on the wall 
 opposite a window have been proven to take away much 
 reflected light, and those with dull surfaces are always to 
 be preferred. 
 
 When unilateral lighting is used, blackboards may 
 safely be placed on three sides of the room. They should 
 never be put between windows, to avoid the possibility of 
 the direct light from the window entering the eye. When 
 the boards are placed opposite the windows, the eyes are 
 adjusted only to the light reflected from the board, and, if 
 the illumination is sufficient, vision is easy and restful. The 
 wall space opposite windows ought to be saved as much as 
 possible for this purpose. 
 
 In well-lighted rooms, the danger from the absorption 
 of light by blackboards is negligible. On dark days and in 
 rooms with insufficient illumination, some relief may be 
 obtained by drawing light colored window- shades over the 
 blackboards. These may be fastened just above the board 
 and pulled down when more light is needed and when the 
 board is not in actual use. 
 
 The style of writing is of importance, vertical writing 
 being conducive to a better position of body and conse- 
 quent proper separation of eyes from objects regarded 
 than the slanting variety. 
 
 Composition of Books. — Of paramount importance is 
 the composition of the books which the child will study. 
 
SCHOOL LIFE AND CARE OF EYES 83 
 
 In classes for the youngest children, i.e,, those under seven 
 years of age, instruction is best given by means of black- 
 boards, large printed diagrams, pictures, and other objects 
 readily seen at a distance, and teaching by word of mouth. 
 After that age, only such books should be chosen as con- 
 form with recognized standards regarding paper, print, 
 etc. Thus the paper should be without gloss, to avoid 
 dazzling reflections. Pure white or paper slightly toned 
 toward cream color afford the greatest contrast with the 
 ink, which should be black. A hard pressed paper is to be 
 preferred, as a soft paper is readily soiled, its surface easily 
 rubbed off and the detritus injurious. The impressions of 
 the type should never be permitted to show through from 
 the other side, and care should be taken that there is ample 
 time for drying the ink before the papers are bound 
 together, to prevent blurring of the type impressions. 
 All illustrations should be of good size and the printed 
 text should not extend in narrow lines at the side. All 
 explanatory legends of pictures and diagi^ams should 
 be in type of a good size, which can be easily read. 
 In preference to reproducing illustrations on highly 
 glazed sheets, half-tone prints on matt paper should be 
 employed. 
 
 An average length of line is to be preferred. Lines 
 which are too long make it difficult for the eyes to pass to 
 the next; those which are too short necessitate too fre- 
 quent a change in direction of the ocular movements. 
 Double columns should not be employed. Good margins 
 are restful to the eye. 
 
 The size of the type-face is the most important factor 
 in the influence of books on vision. The following speci- 
 
84 HYGIENE OF THE EYE 
 
 mens of type have been reproduced from a report ^ of a 
 committee appointed by the British Association for the 
 Advancement of Science to study the influence of school 
 books upon eyesight. They conform with the dimensional 
 rules proposed by the committee and show the smallest 
 sizes which the committee regards as permissible during 
 the age periods cited ( Fig. 36 ) . 
 
 Medical school inspection has done much to improve 
 the condition of children during school life and the atten- 
 tion to ocular conditions and the insistence upon the cor- 
 rection of all existing errors of refraction has been of the 
 greatest value. In the year 1895, before the institution of 
 school medical inspection in Philadelphia, out of 33,000 
 children entering the first grade, only 53 per cent, reached 
 the fourth grade, and only 13 per cent, reached the eighth 
 grade. In the year 1905, when school medical inspection 
 started in this city, out of 34,000 children entering the 
 first grade, 64 per cent, reached the fourth grade, and 22 
 per cent, the eighth grade. '^ 
 
 As Wessels has pointed out, " the correction of ocular 
 insufficiencies not only increases the efficiency of the pupil, 
 but has an important economic value as well, because if a 
 child is backward and remains in the same class for two or 
 three years, it is costing the State two or three times as 
 
 ■^ This report, obtainable at the offices of the Association, 
 BurHngton House, W., London, is of exceeding' value and is recom- 
 mended to all desirous of further information upon the printing 
 of school books, etc. A paper by Black and Vaughn, of Milwaukee, 
 entitled " Protection of the Eyes of School Children," is also of 
 value. 
 
 ^ Lewis C. Wessels, M.D., Ophthalmologist, Bureau of Health, 
 Philadelphia, Pa. 
 
SCHOOL LIFE AND CARE OF EYES 85 
 
 Fig. 36. 
 
 AGE SEVEN TO EIGHT 
 
 This type may be used for books 
 to be read by children from seven 
 to eight years old. The letters are 
 larger than the minimum given in 
 the typographical table. 
 
 AGE EIGHT TO NINE 
 
 This type is suitable in size for books to be 
 read by children from eight to nine years old. 
 The size of the letters is slightly larger than the 
 minimum given in the typographical table. 
 
 AGE NINE TO TWELVE 
 
 This type is the smallest suitable in size for books 
 intended for readers over nine years old. The size 
 of the letters is equal to the minimum given in the 
 typographical table. 
 
 OVER TWELVE 
 
 This type is suitable in size for books intended for practised 
 readers over twelve years old. The size of the letters is in 
 conformity with the smallest dimensions given in the typo- 
 graphical table. 
 
86 HYGIENE OF THE EYE 
 
 much as it should to teach that child. In Philadelphia it 
 costs about $35 per year to teach each pupil. A child is 
 compelled to attend school between the ages of six and 
 fourteen years inclusive, eight years in all. Under normal 
 conditions a pupil 14 years old reaches the eighth grade 
 at a cost to the State of $280; if on account of defective 
 vision the child only reaches the fourth grade in that time, 
 it has cost the State $280, but with only $140 worth of 
 result — a loss to the State of $140. The loss to the child 
 is considerably more, because at the age of fourteen he is 
 likely to be put to work, poorly equipped for the struggle 
 for existence, his earning power is curtailed for the want of 
 an education, so he can contribute little toward his own 
 support, that of his family, or of the State. So again the 
 State loses, and all for the want of suitable glasses for 
 the child." The City of Philadelphia furnishes glasses 
 free to all those who are too poor to provide them. From 
 1908 to 1913, 6310 pairs of spectacles were provided in 
 this way. 
 
 In recent years educators and ophthalmologists have 
 realized the advantages which would be gained by pupils 
 and teachers if scholars with poor vision received their in- 
 struction in separate classes. There has accordingly, in 
 several centres, been instituted special classes for (Children 
 who are very highly myopic and for those who are par- 
 tially sighted from other causes. The following is an out- 
 line which has been adopted in London for the conduct of 
 such classes ^ : 
 
 ^ " The Problems of the Education of the High Myopes and of 
 the Partially Sighted," N. Bishop Harman, F.R.C.S. 
 
SCHOOL LIFE AND CARE OF EYES 87 
 
 " 1. Elementary school for easy treatment as regards 
 eye work. 
 
 " 2. Elementary school for oral teaching only. 
 
 " 3. Myope class. 
 
 " 4. School for the blind and partially blind. 
 
 " 5. Invalided temporarily or permanently." 
 
 Harman says : " To make clear the nature of the defect 
 of the eyes of these children and the limitation of the educa- 
 tion they will receive, the matter is explained personally to 
 the parent of the child, and an explanatory^ notice is issued. 
 It is equally necessary that the teachers to whose care 
 these children are comaiitted should be clear as to the neces- 
 sity for closely watching and limiting their work, and to 
 this end a circular letter is sent to the head teacher of the 
 school to which any such child is admitted." 
 
 In London, children with a myopia of from 5 to 15 D., 
 and with a corrected vision varying from 6/18 to 6/24 
 are admitted to the myopia classes. These classes are all 
 connected with the ordinary schools as "(1) a better 
 scheme of work can be provided by this association; and 
 (2) to establish the class as a separate unit is to run the 
 risk of the children leaving school with a special mark 
 upon them." The scheme of work outlined for these classes 
 is as follows : 
 
 "(1) Oral teaching with the normal children for such 
 subjects as can be taught orally. 
 
 " (2 ) Literary work such as is necessary for the knowl- 
 edge of the ordinary means of communication to be learned 
 without books, pens, or paper, but by the use of black- 
 boards and chalk, the writing to be done in free-arm 
 fashion. 
 
88 HYGIENE OF THE EYE 
 
 "(3) A full use of every sort of handicraft that will 
 develop attention, method, and skill, with the minimum use 
 of the eyes." 
 
 In his valuable paper, Harman goes on to say : 
 
 '' The Class-room. — ^The one necessity of a class-room 
 for myopes is perfect natural illumination. Artificial 
 lighting for these rooms is a negligible consideration. All 
 work other than physical exercises, oral lessons, or games 
 is suspended immediately artificial light is required. 
 
 " The ordinary school desk is unsuitable and the spe- 
 cial desks in use provide for each child a full-sized black- 
 board suitably sloped and at a convenient height for sitting, 
 and also a full- sized horizontal table for handiwork. It is 
 convertible from one use to the other by merely lifting the 
 board. Each room has fitted all around the walls a band of 
 blackboard. The boards are fixed so that they are avail- 
 able for both teachers and pupils without requiring any 
 adjustment. 
 
 " When one group of children is taking oral lessons 
 with the normal sighted in the ordinary school, the teacher 
 will be employed in giving lessons requiring writing, arith- 
 metic, or manual work to another group. The number of 
 children that any one teacher can deal with at the same 
 time must of necessity be less than the same teacher could 
 cope with in an ordinary school. Individual teaching is 
 much more necessary. Further, the desk fitting — the com- 
 bination blackboard and table — takes up the room of an 
 ordinar}^ dual desk. Experience shows that the greatest 
 number any teacher can deal with successfully in any class 
 working at the same subject and at the same time is 
 twenty. 
 
SCHOOL LIFE AND CARE OF EYES 89 
 
 '' The Curriculum, — The oral teaching is taken with the 
 normal children in the ordinary school with which the 
 myope class is associated. By this means the myopic 
 children are kept up to the standard of knowledge of 
 their normal colleagues, and have the benefit of mixing 
 with them in class under the oversight of the regular 
 teachers. 
 
 " The hterary work of the children is done in the myope 
 class upon the blackboards provided for each child, and 
 upon the wall-boards. Letters must be large, and the chalk 
 lines broad and strong, and to secure this the chalk sup- 
 plied should be square-edged and of double the measure of 
 the stock size. The small desk blackboards are marked 
 with white lines two inches apart and the wall-boards four 
 inches apart. 
 
 " In the higher standards the need of some permanent 
 record of the work of the children is felt; and in the 
 higher standards exercise-books are being tried of a novel 
 pattern. They are made up of large black paper sheets, 
 and the wi'iting is done with white crayon, which gives a 
 record of fair durability, but it can be washed off if de- 
 sired. The exercise-books are clipped on to the desk black- 
 boards, and the wi'iting is done free-arm fashion as though 
 on the blackboard, so that none of the dangers of ordi- 
 nary writing, such as stooping over the work, are involved. 
 The eldest of the pupils are allowed to make a permanent 
 record of their work by printing. Two sets of printing 
 types are provided for the use of each class. They are 
 rubber faced black-letter types, one of one-inch height, the 
 other of two-inch height. These letters are mounted on 
 wooden blocks, and the blocks are fitted with lateral pegs 
 and holes, so that they can be joined together to form 
 
90 HYGIENE OF THE EYE 
 
 words. The words are set up and printed upon large 
 sheets of white paper, the record is permanent, and goes 
 to form a class library of scrolls which are useful for 
 subsequent teaching. 
 
 " Physical exercises enter largely into the time-table, 
 and attempts are made to associate some of the games with 
 the instructional work, e.g., large sheets of scenic canvas are 
 now supplied to two schools that have sufficient floor space ; 
 on these the teachers paint outline maps of difl'erent coun- 
 tries, marking out the position of the principal cities, rivers, 
 mountains, etc. ; the children walk about on the floor-maps, 
 learning their geography by travelling it in miniature. 
 With a teacher of resource such methods of instruction 
 possess endless possibilities of interest. 
 
 "The most difficult section of the work to arrange is 
 the manual training. Whatever the work done, it must be 
 such that the fixed attention of the eyes is not demanded. 
 For that reason all sewing- work is prohibited ; it has been 
 tried with a few of the elder girls but was quickly stopped. 
 Knitting, on the other hand, fulfils the necessary condi- 
 tions ; a child that has any aptitude for it soon learns to do 
 it automatically and with little use of the eyes; such chil- 
 dren are allowed to practise it. The junior children (both 
 boys and girls) are taught paper folding, stick laying, 
 felt weaving in colors, and knitting. The seniors and some 
 juniors are taught modelling maps, rough woodwork 
 where measuring can be done with rulers marked with 
 quarter inch marks. Advanced basket work is taught ac- 
 cording to the advanced scheme on workshop principles 
 (but not including raffia work, which is too fine). Bent 
 iron-work is quite satisfactory, particularly for boys; 
 possibly also the netting of hammocks, tennis nets, etc., 
 
SCHOOL LIFE AND CARE OF EYES 91 
 
 for the girls cookery and laundry of a simple kind, just 
 sufficient to give an intelligent insight into the arts of 
 housewifery. 
 
 " These crafts are taught as a training in attention and 
 care; it is not intended that any of the children should 
 enter into competition with the blind in doing this work; 
 for that reason any particular kind of this work is not 
 continued to the point where rapidity and skill are reached. 
 The scheme of education in view for the myopes is not 
 merely technical but general. Many of these children are 
 of high intelligence, and a good general training with 
 special attention to the development of thought, initiative, 
 a good bearing, and clear speech free from objectionable 
 accent and idiom, will fit them for positions of usefulness 
 and responsibility of the in- and out-door type, such as 
 small traders, collectors, agents, visitors, etc. This kind 
 of occupation presents no risk to the eyesight. 
 
 " There is great need for the discovery of more varie- 
 ties of suitable manual work, especially for the use of the 
 older boys. What is wanted in particular is work that can 
 be done in the standing position. Whoever has under 
 consideration the suitability or otherwise of manual tasks 
 for these children has need to consider it from a totally 
 different point of view from that necessary with ordinary 
 children. With the ordinaiy child there has only to be 
 considered the educational and disciplinary value of the 
 work, and possibly the ultimate direct utility to the child, 
 although I maintain that this is of no consideration in 
 comparison with the disciplinary value. But with the 
 myopes there is another matter to be considered. We 
 must ask — ^Can the child do this particular sort of work 
 without undue or too prolonged stooping? Judged by 
 
92 HYGIENE OF THE EYE 
 
 this test there is a great diiFerence between such tasks as 
 carpentry and bent-iron work. In carpentry the head is 
 almost always bent downwards towards the bench, it is 
 quite useless to attempt to raise the bench to a near level 
 of the eyes to prevent stooping, for then the muscles of 
 the arms and shoulders lose all power over the tools, and 
 the work is unduly fatiguing. Bent iron- work, on the 
 other hand, can be done sitting or standing, the table may 
 be at a comparatively high level, and best of all the work 
 is done for the most part with the eye looking straight 
 forward. I have now under consideration the possibility 
 of teaching weaving on frames of mats, carpets, and tapes- 
 try, work that could be done standing to frames hung on 
 the walls. If such work as this should prove practical it 
 will be a valuable addition to our list of suitable handi- 
 crafts. 
 
 " I should like once more to emphasize the idea that 
 handiwork as taught in these classes for the myopes is in 
 no sense a utilitarian affair, it is not done as an apprentice- 
 ship to a life-long work, such as is the case with the blind. 
 It is taught as Latin is taught by the public school-master. 
 The Latin school^master has long since given up the plea 
 of the ' utility ' of Latin as a ' leading to vistas of classi- 
 cal literature,' for the logic of circumstances has driven 
 him to admit, albeit with becoming reluctance, that his 
 pupils never gain more than a nodding acquaintance with 
 the language, but he is strongly entrenched behind the 
 statement that the learning of Latin is the best of all 
 mental disciplines. Handiwork is to the myope school 
 what Latin is to the public school, it is the one great train- 
 ing in care, precision, and control. 
 
 " There is no intention of teachinor a form of liveli- 
 
SCHOOL LIFE AND CARE OF EYES 93 
 
 hood, but of training in methods that will subsequently be 
 valuable in some suitable form of livelihood. This will 
 be made plain when the various forms of work for which 
 myopes are suitable are considered. After examining 
 a long list of the available occupations for London boys 
 and girls, I have drawn up the following as those for 
 which the myopes are fit. There are two grades of 
 work ; those most suitable for them, and those of secondary 
 suitability. 
 
 Boys 
 
 First selection: 
 
 Nursery gardening. 
 
 Poultry farming. 
 
 Messengers. 
 
 Assurance agents. 
 
 Travellers and canvassers. 
 
 Rent collectors. 
 
 Hawkers and street traders. 
 
 Shopwork under good conditions. 
 
 Piano-tuning. 
 
 Second selection: 
 
 Stick and pipe mounting. 
 
 Basket-making. 
 
 Some branches of brush-making. 
 
 Girls 
 
 First selection: 
 
 Florists' work. 
 
 Waitresses in tea shops. 
 
 Dairy shops. 
 
 Under nursemaids (no sewing). 
 
 Creche attendants. 
 
 Helpers at mothers' schools. 
 
 Helpers at special schools and dining centres. 
 
94 HYGIENE OF THE EYE 
 
 Showroom work. 
 
 Light warehouse work (packing). 
 
 Second selection: 
 Box-making. 
 Cork-sorting. 
 
 Envelope folding, cementing, and black-bordering. 
 Show-card mounting. 
 Some branches of brush making. 
 Stockroom work. 
 
 " These lists show at a glance that the kinds of work 
 placed in the first and most suitable selection are of the 
 outdoor type, or those that enable the worker to be out and 
 about, standing and moving, and with a minimum of close 
 eye work. These kinds of work are doubly suitable, for the 
 general health is likely to be the better for the freedom of 
 movement enjoyed, and with the improvement in the gen- 
 eral health the state of the eyes is likely to be benefited. 
 Next after these comes the second selections, all these are 
 of light tasks, that do not unduly involve the use of the 
 eyes ; but they involve sitting and stooping throughout the 
 whole period of work, conditions that are neither good for 
 the body nor for the eyes. When, therefore, we look at 
 the teaching and practice of manual work in the myope 
 class in the light of the possible future of the children, it is 
 evident that we want no more of it than is necessary to 
 teach them methods and habits of precision. And just so 
 much as will engage their minds with the possibilities of 
 creating things as will withdraw them from the fatal 
 snare of living in a world of reading and book-thinking. 
 The manual work serves as both a discipline and a 
 distraction." 
 
 The Partially Sighted and the Partially Blind. 
 
SCHOOL LIFE AND CARE OF EYES 95 
 
 — Under this class is grouped border-like cases which 
 differ only from the blind in the degree to which vision 
 has been reduced by the various diseases which have low- 
 ered visual acuity. 
 
 The conditions which are responsible for blindness in 
 children have been classed by Harman under the following 
 heads : 
 
 1. Blindness due to causes which are in their nature 
 accidental. 
 
 2. Blindness due to general disease in which the child 
 is born and shapen. 
 
 3. Blindness due to congenital deformities. 
 
 The children in the first group are normal save for 
 lowered vision. Those in the second, however, according 
 to Harman, which comprises 30 per cent, of the total child 
 blind, bear the evidence of disease elsewhere, and are 
 often mentally inferior. The third group comprises about 
 20 per cent, of the partially blind and is often associated 
 with defects in other organs. In dealing with scholars in 
 these groups Harman states: " The state of their vision 
 cannot be the sole determining factors of their places of 
 education; the likelihood of their educability in view of 
 the nature of the disease that made their eyes defective 
 must be considered, and also the possibility of this same 
 disease reasserting its maleficent influence and destroying 
 still further both sight and wits. The case of a child with 
 damaged eyes the result of ophthalmia neonatorum is 
 simple of determination, if it sees 6/18 it is a fit subject 
 for a myope class, its wits are as likely to be good as any 
 ordinary child, and there is no likelihood of the recurrence 
 of the inflammation of the eyes that damaged the sight in 
 the beginning. It is otherwise with the child whose eyes 
 
96 HYGIENE OF THE EYE 
 
 have been damaged by some inflammation springing from 
 a syphilitic inheritance. That disease affects the whole 
 body, and there is too often a recurrence of the disease that 
 will still further reduce sight or even destroy the remnant, 
 and at the same time so benumb the mental faculties as to 
 lay waste all past educational gain, and efl*ectually pre- 
 vent any future effort. With such a child the admission 
 to a myope class, even though justified by the character 
 of the vision existing at the time of examination, must be 
 the subject of special note, that the child be not pressed 
 or allowed to enter into competition with its short-sighted 
 and smart-witted colleagues, lest the strain of the work 
 reduce its bodily resistance and induce a relapse of the 
 disease that originally brought it there." 
 
 Special classes for children with defective eyesight have 
 been in operation in Boston and Cleveland for several 
 years past and are about to be installed in several other 
 American cities.^ 
 
 Some Hints Regarding the Care of the Eyes 
 IN General 
 
 While the importance of properly caring for the eyes 
 is not as great in adults as in children, the formative 
 period of the growth of the eye having passed and with 
 it the greatest danger to the development of ocular errors, 
 nevertheless the eye remains a more or less sensitive organ 
 until death, and the wise man will naturally conserve its 
 strength as far as he is able. With the extraordinary de- 
 
 * Those interested in the education of children with defective 
 eyesight would do well to obtain " The Eighth Annual Report of 
 the Massachusetts Commission for the Blind, 1914." 
 
SCHOOL LIFE AND CARE OF EYES 97 
 
 mands placed upon the eyes by reason of the increased 
 desire to read, through the multiphcity of magazines and 
 books which are constantly published and the ease afforded 
 their use by the excellence of present-day artificial light- 
 ing, there is much danger of the abuse of these organs. 
 Common-sense dictates, therefore, that short periods of 
 rest should interrupt all kinds of close work, during which 
 the eyes should be directed for a time out of the window or 
 on distant objects. After a day of continuous application 
 in office work, it is unwise to devote more than an hour or 
 possibly two hours to reading in the evening. A word of 
 caution may be addressed to those who make a practice of 
 reading in a recumibent posture, for under such circum- 
 stances it is difficult to regard the book at a favorable angle. 
 If for any reason, such as illness or fatigue, reading 
 must be pursued in this attitude, care should be given 
 that the body is made as upright as possible, and that 
 the object regarded is held well below the horizontal plane 
 of the eyes. 
 
 Reading or close work should never be persisted in 
 when drowsy or physically tired. The ocular muscles are 
 relaxed under such conditions and are only stimulated 
 into action by a conscious effort of the will. 
 
 Veils, though usually worn for other purposes, may be 
 useful in protecting the eyes from glare and dust. Light 
 chiffon veils are useful for this purpose, black, blue, and 
 green being the preferable colors. Dotted and very thick 
 veins should never be worn. 
 
 Books printed in very small type or on poor paper 
 should be discarded, and better editions obtained. On ac- 
 count of the attendant vibrations, reading on trains and 
 moving vehicles of all kinds is more or less injurious and 
 
 7 
 
98 HYGIENE OF THE EYE 
 
 should never be practised by a poor illumination. In- 
 dividuals with weak eyes should reduce their newspaper 
 reading to a minimum and this only in a good light, on 
 account of the poor type and paper generally used in this 
 popular form of literature. 
 
 As the health of the eyes is dependent in large meas- 
 ure upon the health of the body, it behooves the individual 
 solicitous of his ocular strength to properly care for his 
 physical condition. One or more hours should be spent 
 daily in the open air and walking should be practised when 
 the more active exercises cannot for any reason be indulged 
 in. A plentiful supply of fresh air should enter the sleep- 
 ing-room, which should be absolutely free from light of 
 any kind. The bowels must be kept regulated and par- 
 ticular care given the teeth and the nasal passages, as dis- 
 orders of these neighboring structures frequently give rise 
 to ocular symptoms. 
 
 If the eyes feel hot and uncomfortable after exposure 
 to irritants or undue strain, they may be washed with an 
 eye bath containing a saturated solution of boracic acid. 
 Bathing the closed lids with either very warm or cold water 
 is refreshing and beneficial. The habit practised by some 
 of partially immersing the head and opening and closing 
 the eyes under water is not to be recommended. 
 
 Certain amusements at present much in vogue are 
 somewhat harmful to the eyes. Among these may be 
 mentioned automobiling in open cars and the moving 
 picture theatres. The former is tiring by reason of the 
 rapidity with which the eyes must adapt themselves to 
 passing objects and from the fixed gaze of the driver 
 and his anxious passengers upon the road. Suitable 
 
SCHOOL LIFE AND CARE OF EYES 99 
 
 goggles will relieve the irritation of the eyes from wind 
 and dust. 
 
 Moving Pictures. — ^\¥hile the great majority of those 
 who suffer from eye-strain after watching moving pictures 
 can usually obtain relief from properly fitted glasses, the 
 character of the films is sometimes of such a nature that 
 there is no escape from more or less ocular pain, even 
 though they be regarded for a comparatively short time. 
 Usually the promoters of moving picture theatres, alive 
 to the demands of the public, furnish excellent films and 
 do what they can to insure the comfort of their patrons. 
 Motion pictures, however, have become such a universal 
 source of instruction as well as amusement, that it seems 
 wise to insist upon several essentials in regard to them. In 
 the first place, glass screens should be preferred to all others, 
 this type of screen producing an ideal reflecting surface 
 and producing pictures without glare and with a minimum 
 of distortion. Experts agree that the auditorium should 
 be as light as possible without obscuring satisfactory de- 
 tail in the picture. The indirect system of lighting is to be 
 preferred for this purpose. 
 
 When possible, a seat should be chosen near the centre 
 of the house, and within natural limits, the farther one is 
 seated from the screen the better. Films should be dis- 
 carded after they become scratched and " rainy." Steadi- 
 ness and the absence of flicker in the picture may be ob- 
 tained by mounting the projecting machine on a solid 
 foundation, by proper apparatus and skilful adjustment 
 by a capable operator. Finally, a period of rest should 
 be permitted between the reels to ofl*set the fatigue of 
 concentration. 
 
 AuTOMOBiiJNG. — In addition to irritation and strain 
 
100 HYGIENE OF THE EYE 
 
 upon the eyes occasioned by automobiling already referred 
 to, there is another ocular phase of this popular means of 
 locomotion which demands consideration; namely, the 
 necessity that the driver of the car possesses a requisite 
 amount of sight. Many European cities assure this be- 
 fore granting a chauffeur's license, and it would be well if 
 this practice were generally adopted in our own country. 
 Two good eyes are essential, for a restricted vision in one 
 eye limits the field of vision below the safety point. Near- 
 sighted drivers who depend upon lenses to give them ade- 
 quate vision, should be rejected, as the exposure to rain 
 and fog which is at times necessitated in bad weather, 
 mists the glasses to such an extent that they become 
 useless. 
 
CHAPTER YII 
 
 ARTIFICIAL LIGHTING 
 
 By Herbert E. I^t:s, Ph.D. 
 
 FORMER YICE-PRESIDEXT OF THE ILLUMINATING EXGINEER- 
 
 IXG SOCIETY^ CORRESPOXDIXG MEMBER OF THE ILLU- 
 
 MIX-ATIXG EX^GIXEERIX^G SOCIETY OF GREAT 
 
 BRITAIN 
 
 INTRODUCTION— ABOUT KINDS OF LIGHTS 
 
 Good artificial lighting is not a question of the kind of 
 illuminant but of how the illuminant is used. Oil, gas, 
 and electricity can each be used to produce satisfactory 
 lighting, and each can be abused. The modern lighting 
 specialist can so plan a scheme of illumination that any 
 kind of light may be employed to give the desired lighting 
 effect, and none but an expert can tell which kind it is. 
 The whole j^roblem of satisfactory artificial lighting (given 
 a steady unflickering light such as all modern illuminants 
 are) is a matter of the proper disposition of the light with 
 respect to the objects to be lighted, and with respect to the 
 people who are to see these objects. 
 
 A Very Importaxt Fuxdamextal. — The most fun- 
 damental principle of good artificial lighting is that the light 
 must shine on the object of interest but not in the eyes of the 
 observer (Figs. 37 and 38) . All shades, globes, reflectors, 
 and special arrangements of the light with respect to the 
 walls and ceilings, if correctly conceived, should have this 
 simple object constantly in view. Other features are to be 
 sought as well, as is shown later, but this is the chief. Try, as 
 
 101 
 
102 HYGIENE OF THE EYE 
 
 an experiment, looking at a picture, first with an unshielded 
 light alongside and a little in front, then with the light 
 
 Fig. 37. — The wrong way to use a light. It shines in the workman's eyes and decreases his 
 ability to see his work. The eye3 should never be exposed to an unshielded light source. 
 
 shielded from the eyes, say with the hand. In one case the 
 eyes are blinded with the light; in the other the picture is 
 
ARTIFICIAL LIGHTING 103 
 
 clearly seen, although no more light falls on it than before. 
 Light falling in the eyes instead of on the object is twice 
 lost. 
 
 Shades and Reflectors. — Never let an unshielded 
 
 Fig. 38. — A good way to light a desk. The lamp is completely shielded from the worker's 
 eyes by the opaque reflector, which at the same time throws a flood ot light on the desk. By 
 placing the light to the left side the shadows tall correctly tor writing, and reflections from glossy 
 paper surfaces are directed away from the eyes. A desk light alone is not sufficient for comfort, 
 but should be supplemented by some general diffused illumination. 
 
 light be visible. At the same time, the effort should be made 
 to let a large part of the light fall on the object of interest — 
 the book page, the sewing, the machine (Figs. 39 and 40) . 
 To achieve this double object, shades and reflectors of vari- 
 ous types are essential. A shade is in general a m'e re obstacle 
 
104 HYGIENE OF THE EYE 
 
 or screen, interposed between the source of light and the 
 eye. It may, for instance, be a cylinder of opaque or trans- 
 lucent material about a table lamp, permitting the unob- 
 
 FiG. 39. — The wrong way to use a table lamp. Dazzling reflected images of the light come 
 from the book page and polished table top, and cannot be escaped by the reader in this position. 
 This condition is almost but not quite as bad as though the lamp had no shade to prevent the 
 light from shining directly into the eyes. Avoid fringes on lamp shades. Their wavering 
 shadows are excessively trying to the eyes. 
 
 structed light to go upward and downward, but not hori- 
 zontally toward the eye. Or it may be a half cylinder in 
 front of a wall bracket, permitting the light to go up- 
 
ARTIFICIAL LIGHTING 
 
 105 
 
 ward, downward and to the wall, but not straight out. A 
 reflector differs from a mere shade in that its inner sur- 
 face is highly reflecting, and so shaped as to direct the 
 
 Fig. 40. — The correct way to use a table lamp. The table is provided witih a dull coveri 
 and the book is held sideways to the light, which for reading may come from either side, or 
 over either shoulder. No disturbing reflections reach the eyes. A table lamp alone is not 
 sufficient light for a room, unless it has an open top which throws light to the ceiling and thus 
 provides general diffused lighting to help out the locally intense illumination. 
 
 light in a definite direction. Thus there are reflectors which 
 concentrate the light over a small space, such as a desk 
 top, and other reflectors which spread the light over large 
 
106 HYGIENE OF THE EYE 
 
 areas, such as the floor of a room. Close, fine, difficult 
 work will often call for the concentration of light given 
 only by a properly selected reflector. A reflector is not 
 necessarily a shade, but in all ordinary cases it should be. 
 If the light source is not concealed by the reflector, or at 
 least greatly reduced in brightness, for the normal posi- 
 tion of the user of the light, it is not correctly designed. 
 
 Large and Small Light Sources — Their Charac- 
 teristics. — A simple but useful way to classify artificial 
 light sources is by size. We have light sources of small 
 area, such as an incandescent electric lamp filament, or a 
 gas mantle. We have light sources of large area, such as 
 an illuminated ceiling or side- wall, either of which serves 
 as the real illuminator of the room, even though the light 
 originally comes from, a small point-like source. 
 
 The illuminations due to these two classes of light 
 sources are called respectively directed and diffused illu- 
 mination or lighting. By directed light we get sharply 
 defined shadows. By difi'used light the shadows become 
 indefinite or soft, and can even be practically missing, if 
 the source of difl*used light be large enough. Each kind 
 of lighting has its place. Directed lighting, with its defi- 
 nite shadows, is adapted to places where differences in the 
 relief of various parts must be readily appreciated, as in 
 type setting, some kinds of sewing, and other localized 
 work, especially if the light falls somewhat from the side. 
 Diffused lighting, with its absence of contrasting illumi- 
 nated and shadowed spots, is adapted to large spaces where 
 all parts should have some light — to general rather than 
 localized activities. It goes around corners and lights 
 those places which a directed light would leave in objec- 
 tionable obscurity. 
 
ARTIFICIAL LIGHTING 107 
 
 The diif erence in the kind of illumination provided by 
 large and small light sources is not the only important 
 difference between them. A large area light source is 
 much less annoying to look at than a small one of the same 
 light giving power. True it is that the light source should 
 never be looked at, but it often happens that it obtrudes 
 itself into the field of vision in a way that cannot be entirely 
 avoided. For instance, where work is being done on pol- 
 ished metalware , many bright surfaces reflect the light 
 source to the eyes, in practically undiminished brilliancy. 
 In such cases the only relief — and it is only partial at 
 that — is to spread out the light source as much as possible, 
 thereby making it less brilliant, and so less irritating. This 
 can be done by covering the light with an opal or milk 
 glass, by frosting the lamp bulb, if it is an electric light, 
 or by directing the light upon a large dull white surface — 
 the wall or the ceiling — which then becomes the light 
 source. 
 
 All modern light sources are too bright to be looked at 
 directly, and in order to minimize the dangers due to their 
 being accidentally seen they should be spread out by dif- 
 fusing surfaces as much as is compatible with the kind 
 of work for which they are to be used. Usually even 
 where directed light is essential the electric lamp filament 
 or gas mantle can be enclosed in a diffusing device, such 
 as a frosted or opal globe or reflector, which will enor- 
 mously reduce its annoying character if directly viewed, but 
 will at the same time leave it small enough to give the 
 necessary relief -revealing shadows. 
 
 Contrasts to be Avoided. — Beside the question of the 
 actual brightness of a light, which has just been discussed, 
 is the question of the contrast it makes with its background 
 
108 HYGIENE OF THE EYE 
 
 or surroundings. If a gas mantle is viewed against the 
 bright sky in the day-time it is so little different in bright- 
 ness that it causes no discomfort. But against the black 
 night sky it is well nigh unbearable. This illustrates the 
 importance of preventing big contrasts between either the 
 lighting devices and their backgrounds, or between the light 
 and dark parts of the field of view. No light source — by 
 which is here meant the entire lighting device as seen, 
 shade or reflector and all — should be in such contrast with 
 its immediate surroundings that these may not be looked 
 at in entire comfort at the same time as the light. A bare 
 electric lamp in a wall bracket on a dark wood panelled 
 wall forms a contrast to which the eye should never be 
 subjected. The various illuminated objects in a room 
 should never be so different in brightness that the eye is 
 strained in attempting to look from one to another, or 
 must wait a perceptible period to become adapted, as it is 
 called. The practice of working at a table brightly illumi- 
 nated by a lamp which is the only light in the room is to 
 be condemned for this reason. On looking away from the 
 table the eye practically falls over a light precipice. 
 
 The Direction of Lighting. — Entirely satisfactory 
 lighting is not merely a question of avoiding irritating or 
 annoying conditions. The illuminated room must be pleas- 
 ing in appearance — it must appeal to the esthetic sense, 
 and to our accustomed ideas of fitness. Probably nothing 
 contributes more to this aspect of lighting than the direc- 
 tion from which the light comes, and the part of the room 
 on which the major part of the light falls. The commonest 
 arrangement of lighting fixtures is that which makes the 
 light come from directly ahove, but this is probably the 
 least pleasing direction of all. Shadows then fall directly 
 
ARTIFICIAL LIGHTING 
 
 109 
 
 downward, resulting in a loss of our power to properly 
 appreciate the sizes and positions of objects. Artists have 
 long recognized that nature looks its best when lighted by 
 the rising or the setting sun, and looks its worst when the 
 sun beats straight down. For the same reason that a tree 
 
 Fig. 41. — Dark walls waste light and prevent diffusion. These two booths are illumi- 
 nated by exactly the same light. In the one with light walls, all the details of the statue are 
 illuminated; in the other the statue shows only by harsh contrasts. 
 
 is a more pleasing sight when its shadow falls away to one 
 side than when the shadow is a mere blotch about its root, 
 so a room with a goodly share of its light striking across it 
 is more satisfactory than if lighted solely from above 
 (Fig. 41). 
 
 For the best appearance of a room it is necessary to 
 
110 HYGIENE OF THE EYE 
 
 yield in some degree to what we have become accustomed 
 to by day, and to some of the characteristics of our furnish- 
 ings which owe their origin to daylight conditions. Most 
 daylighting of interiors is by windows facing the sun or 
 sky. A very large amount of light falls from the window 
 to the floor and on to comparatively dark floor coverings 
 and furniture. If our room by night is not to look top- 
 heavy and gloomy, it is desirable to throw a large amount 
 of our artificial light to the floor and furniture. 
 
 Yet another concession to our ingrained idea of fit- 
 ness is to avoid concealing entirely the point of origin of 
 the light. The light source is a centre of cheer and no 
 mean part of the decorative makeup of the comfortable 
 room. Where the lighting is entirely diffused, much of 
 the life and coziness of the room is lost. But this natural 
 yearning for an unmistakable centre of light radiation does 
 not by any means call for a dazzling light shining in the 
 eyes. It is quite sufficient for the shade or reflector sur- 
 rounding the lamp to be a little brighter than its surround- 
 ings in order to satisfy this psychological need. Chief 
 dependence should be placed on the clear revealing of the 
 direction from which the light comes, by the naturally 
 greater illumination near the light source and by the direc- 
 tion in which the shadows fall. 
 
 The Most Satisfactory Arrangement of Lights. 
 — ^In the nature of things there cannot be a standardized 
 arrangement of lights to give the best effect, because every 
 kind of room and every use to which a room is put makes 
 different demands. But in general it may be said that the 
 problem of satisfactory lighting — assuming that the neces- 
 sary precautions as to concealing the light sources, avoid- 
 ing contrasts, and so on, have been observed — reduces to 
 
ARTIFICIAL LIGHTING 111 
 
 finding the proper balance between directed and diffused 
 light, and between the amounts of light in the various 
 parts of the room. Extremes are to be avoided. Thus 
 entirely diffused lighting produces a dead, fog-like effect. 
 
 Fig. 42. — A common type of fixture planned to give diffused illumination. The light 
 source is in the opaque bowl which reflects the light rays upward to the ceiling. Used alone 
 this type of fixture is apt to be inadequate, because the lower part of the room is deficient in 
 light. It should be helped out either by pendent lamps to give downward directed light, or by 
 table lamps. 
 
 On the other hand, too exclusively directed a light is apt 
 to result in violent contrasts of light and shadow (Figs. 
 42, 43, and 44). 
 
112 HYGIENE OF THE EYE 
 
 A safe rule is that there should be enough diiFused 
 light, from illuminated walls and ceiling, so that all parts 
 of the room can be clearly seen. To this add directed light 
 at the points of interest — the work table, piano, or book 
 
 Fig. 43. — Another type of fixture designed to give diffused illumination. A translucent 
 bowl, forming with the ceiling, a large area light source. In a small room this type of light may 
 suffice for both general illumination and for the work table or desk. If so used it should be 
 placed high enough over the desk to be well out of the line of vision, or should be behind and to 
 the left of the worker. 
 
 page. The amount of this directed light will vary greatly 
 according to the kind of room. In the dining-room a very 
 considerable concentration of light on the table is permissi- 
 
ARTIFICIAL LIGHTING 
 
 113 
 
 ble and desirable. In the small living-room or library, 
 rather strong local lighting makes for coziness. But in a 
 public auditorium or ball-room all parts demand nearly 
 
 Fig. 44. — A well-considered side-wall light. Bright lamps aj^uinst dark walls are all too 
 common. In this floor standard the light is concealed by a large area, low brightness shade, 
 which obscures it only from the direction of the room. In back the light falls on the white 
 window curtains, which with the ceiling and floor serve as sources of diffused light. Directed 
 light passing out beneath the shade illuminates book page or work. 
 
114 HYGIENE OF THE EYE 
 
 the same amount of light, which may be accomphshed by a 
 very high intensity of diffused light or by many well- 
 distributed local directed lights. 
 
 Lighting Fixtures.^ — The practical working out of 
 the principles of lighting depends upon the placing of the 
 piping or wiring outlets, and on the choice of lighting fix- 
 tures. The ideal way is to plan the lighting with the house, 
 keeping definitely in mind the use of each room, together 
 with the kind of furniture and its arrangement. But more 
 often than not the outlets are already in place when the 
 future occupant of the room first sees it, and the whole 
 problem becomes one of choosing fixtures to make the best 
 use of the outlets provided. These are not always in the 
 best places, and even if they have been properly placed on 
 the expectation of a certain use for the room, they may not 
 suit the use for which the room is later put. It is always a 
 safe thing, and usually possible, to have additional base- 
 board or other portable lamp connections installed. These 
 permit the use of different forms of fixtures, according to 
 the use to which the room is put or the taste of the 
 occupant. 
 
 Four types of lighting fixture are available, classified 
 according to the mode of support, or the position they 
 occupy in the room — ceiling fixtures, wall brackets, floor 
 standards, and table lamps or " portables." In each of 
 these forms examples are to be found planned to give en- 
 tirely diffused, entirely directed, or mixed illumination. 
 Where there are several outlets the proper balance can be 
 secured by a combination of a diffused lighting fixture 
 with directed ones. For instance, the diffused light may 
 come from a ceiling fixture of the suspended bowl type, 
 the directed from a table lamp or floor standard which 
 may direct all its light downward, either of these alone 
 
ARTIFICIAL LIGHTING 115 
 
 not being fully satisfactory. Where there is but one out- 
 let a fixture to give both the diffused and the directed 
 light should be chosen. Such, for instance, is a table lamp 
 which not only sends light down to the table, but through 
 its open top sends light to the ceiling to be there diffusely 
 reflected to all parts of the room. 
 
 A cardinal rule in the selection of lighting fixtures is 
 that they should be chosen not because they look well as 
 examples of metal and glass work by day, but for their 
 appearance and performance at night when lighted. Artis- 
 tic appearance is very desirable, but it should be in addi- 
 tion to, not at the expense of, serviceability. 
 
 Other Things Nearly as Important as the Lights 
 Themselves. — ^Furniture and wall coverings are a vital 
 part of the lighting scheme of the room. Dark walls ab- 
 sorb light, thus demanding the use of more gas or elec- 
 tricity to give adequate illumination. But more serious 
 than the loss of light caused by dark walls or ceiling is 
 the fact that with them it is almost impossible to obtain 
 an adequate amount of diffused light, or to avoid exces- 
 sive contrasts between lighted and unlighted objects. 
 Walls, and especially ceilings, should be light. Dark wood 
 wall panelling, and carved wood ceilings, which we copy 
 from our Elizabethan ancestors who lived mostly by day- 
 light, are practically incompatible with efficient or com- 
 fortable artificial lighting. 
 
 Glossy surfaces should be carefully avoided in the fur- 
 niture or objects used in a room. A polished table top, or 
 one covered with a glass plate, reflects the unshielded light 
 of the table lamp or overhead fixture directly into the eyes, 
 and is just as bad as never-to-be-faced Tmconcealed light. 
 Books or magazines printed on glossy paper are to be 
 shunned for this same reason. Fortunately publishers are 
 
116 HYGIENE OF THE EYE 
 
 being brought to a realization of the evil effects on eye- 
 sight of glazed paper reflections, so that this souixe of 
 glare may before long be done away with. 
 
 Another thing nearly as important as the placing of 
 the lights is the position of the occupant of the room. Even 
 in rooms where the lights are poorly arranged it is often 
 possible for a person to so place himself that the annoying 
 lights are no longer seen. So too, in reading or writing, 
 such disturbing reflections as may come from paper or 
 table top can be escaped by having the light come from 
 the side or over the shoulder. A safe rule is never to face 
 the point from which the light comes. 
 
 Finally, let it be remembered that if the lighting seems 
 unsatisfactory it may mean nothing more than that the 
 eyes have become tired from their day's work before the 
 artificial light is used at all. The remedy may lie in the 
 hands of the oculist instead of the lighting expert. 
 
 Quantity or Light. — The quantity of light to be 
 provided for is one of the first things considered by the 
 illuminating engineer. It should be about the last thing 
 for the layman to attempt to make a judgment upon. 
 This is because the layman is altogether too apt to be led 
 astray by any one of half a dozen other defects of a light- 
 ing system, which must first be removed before it is possi- 
 ble to decide whether the amount of light is sufficient. 
 Never conclude that more light is needed until every light 
 now used is properly shielded, until all excessive contrasts 
 have been remedied, until all glossy reflections have been 
 done away with. If then there is difficulty in seeing well 
 enough for the work in hand, the lighting units may be 
 increased in size, or more added. It is quite futile to at- 
 tempt to improve the lighting by adding more light if every 
 addition of light adds an equal amount of glare. 
 
CHAPTER VIII 
 
 DAYLIGHT ILLUMINATION OF ROOMS AND 
 BUILDINGS FROM AN ARCHITECTURAL 
 STANDPOINT 
 
 By William Copelaxd Furber 
 architect axd consulting engineer^ phila.^ pa. 
 As a civilized man spends, in all probability, consider- 
 ably more than one-half of his time " under cover," the 
 lighting of buildings, both natural and artificial, as an eco- 
 nomic factor, has not, until quite recently, been fully recog- 
 nized. This is undoubtedly due to the fact that the study 
 of lighting systems has not been considered apart from 
 utilitarian, structural, or architectural considerations. 
 
 Artificial Lighting. — The introduction of artificial 
 lighting units of great intensity, such as the arc light, and 
 the high powered incandescent electric and gas lamp, was 
 probably the determining consideration in the study of 
 methods whereby the intensity of light could be mellowed 
 by equitable diffusion, and in the last few years the inves- 
 tigations along this line have been productive of far-reach- 
 ing results in the artificial lighting of buildings. It seems 
 remarkable in looking back over the crude and unsuccessful 
 attempts at lighting which were prevalent in the quite re- 
 cent past that devices for diffusing artificial light were not 
 devised long ago. The possibility of simulating daylight 
 by artificial means, and particularly in such parts of build- 
 ings as it is not possible or desirable to introduce natural 
 light, such as large areas below pavement levels, floor areas 
 not adjacent to windows, and in auditoriums where exter- 
 
 117 
 
118 HYGIENE OF THE EYE 
 
 nal sounds had to be eliminated, has profoundly modified 
 the design of buildings and has reduced to almost a negli- 
 gible degree the dependence upon natural light. 
 
 With the perfection of mechanical apparatus for sup- 
 plying sweet, clean, washed and humidified air to any part 
 of the building, and with the mechanical methods of ex- 
 hausting vitiated air, the problem of the architect has been 
 greatly altered, so that to-day large rooms and floor areas 
 can be successfully lighted and ventilated without regard 
 to their local environment ; as exemplified in the best types 
 of the modern auditorium, in the commodious basements 
 of the large department stores of the best class, and in the 
 underground rooms of large metropolitan hotels devoted 
 to restaurants, kitchens, etc. 
 
 In another chapter of this book, the evil effects upon 
 the structure of the eyeball, due to the concentration of 
 the vision of young children upon the printed page, is 
 touched upon and this fact should be brought home to the 
 educational authorities in such a way that the daylight 
 illumination of school-rooms and the effects of reflection 
 from the side- walls will be more carefully considered, and 
 the best methods employed to conserve the eyesight, than 
 is at present possible under the existing rules. The eye- 
 sight of children and teachers during school careers de- 
 teriorates rapidly, because of the great injury that 
 frequently results from the improper lighting of the school- 
 rooms. 
 
 School-rooms must be illuminated in such a way as to 
 exclude all the effects of glare. The problem of glare has 
 been investigated and the maximum hygienic value for illu- 
 minants has been found to be approximately two and one- 
 half candles for each square inch of illuminated surface; 
 that is, no source of illumination, either direct or indirect. 
 
DAYLIGHT ILLUMINATION 119 
 
 should exceed this value of two and one-half candles per 
 square inch of space. It must also be remembered that the 
 impression of glare upon the eyes from the source of light 
 depends very greatly upon the background against which 
 it is seen. A glowing illuminant without a shade, or an 
 incandescent mantel or filament without a protector seen 
 against dark velvet, will be very much more trying to the 
 eyes than will the same source of light with a white paper 
 behind it. All these evils of glare, however, can be over- 
 come by the substitution of indirect lighting on the ceil- 
 ings of such school and other rooms. 
 
 The intensity, amount and distribution of artificial 
 light and its effect upon the color values of rooms and 
 their contents, have been studied according to scientific 
 methods and the results of these studies are available for 
 the student, so that a mere reference to them in this paper 
 must be sufficient. 
 
 Natural Lighting. — In the design of buildings, we 
 all know, of course, that architectural design in tropical 
 countries has led to the use of large wall spaces and small 
 window openings, while in the high latitudes the converse 
 is true, and architectural forms have been developed in 
 which the glass surface occupies a large proportion of the 
 wall surface, as exemplified in the Tudor and Elizabethan 
 types, but these influences have not yet seriously affected 
 commercial architectural design, excepting in several 
 classes of buildings, notably factory and school buildings. 
 
 In the construction of factory buildings, the recogni- 
 tion of the desirability and necessity for an abundance of 
 daylight has fortunately been rendered esisy of accom- 
 plishment by fundamental changes in the structural de- 
 sign of buildings, and by the invention of what is known as 
 steel sash. In the design of such buildings, the substitu- 
 
120 HYGIENE OF THE EYE 
 
 tion of structural framework of steel or reinforced concrete 
 for masonry walls and piers, has rendered easily possible, 
 the utilization of large areas of external walls for window 
 openings, which were formerly required for structural sup- 
 port, and as a result of the utilization of these two agencies, 
 the external walls of factory buildings to-day consist of 
 from fifty to ninety per cent, of glass, and of these two 
 agencies, the steel sash has probably done more toward 
 this desirable end than the latent possibilities of skeleton 
 construction alone. 
 
 In the design of school buildings, the usual modern re- 
 quirement that the window area shall not be less than 
 twenty per cent, of the floor area has markedly affected 
 the architectural treatment of such educational buildings, 
 and the further requirement of unilateral lighting, which 
 is gradually being insisted upon as the only correct method 
 of lighting school-rooms, is having a salutary effect also in 
 the design of such buildings. In some States, the educa- 
 tional authorities permit light at both the sides and rear 
 of the room, in entire disregard of the detrimental effect 
 of such a method of lighting on the eyes of the teacher, who 
 is compelled to work facing the light. It is to be hoped 
 that the requirements for lighting all school-rooms will 
 soon insist upon unilateral lighting alone. It should be 
 understood, of course, that this requirement for unilateral 
 lighting does not prohibit skylighting in the ceiling where 
 conditions render this desirable form of lighting possible. 
 The lighting of school-rooms has not yet been given the 
 attention that its importance demands (Fig. 45). 
 
 In fixing the ratio of window area to floor space in 
 school buildings, the State Boards of Education should 
 take into consideration the exposure of the windows, for 
 the value of the light admitted to the room is determined, 
 
DAYLIGHT ILLUMINATION 
 
 121 
 
 IP 
 
 
 t^ 
 
 m=t 
 
 Zar:*^I£: 
 
 
 
 :t_-t_^-=tr 
 
 __1 
 
 Fig. 45. — Proposed high school building. 
 
n2 HYGIENE OF THE EYE 
 
 of course, very largely by the character of the environment. 
 In city streets with high buildings adjacent, the amount 
 of light admitted to the school-room is necessarily very 
 much less than in the open country where there is no ob- 
 struction to the light from the sky. The orientation of 
 the rooms also is not usually considered. In fixing the 
 ratio of window areas, it should also be remembered that 
 rooms with a southerly exposure necessarily receive more 
 light than those with a northerly exposure, and there is 
 no proper excuse for a failure to recognize this important 
 diiFerence in prescribing the requirements for the lighting 
 of such buildings. If a twenty per cent, ratio was needed 
 on the south side, considerable more is needed on the north 
 side, and over and beyond the requirements for daylight, 
 the hygienic value of sunlight should be given due recogni- 
 tion, which would result in penalizing northern exposures. 
 If the State Boards of Education favored the southern 
 exposure in some such way, more consideration would be 
 given to the selection of school sites than is now ordinarily 
 the case. While north light is to be preferred for many 
 occupations where sunlight is not permissible, this consid- 
 eration does not apply to school-rooms. In many instances, 
 however, the local environment does not permit the admis- 
 sion of a sufficient amount of light, under which condition 
 a resort to a mechanical means for overcoming this defi- 
 ciency is necessary, and prismatic glass can be used. 
 
 The great value of prismatic glass in the lighting of 
 school-rooms has not yet received proper recognition from 
 the educational authorities who prescribe the requirements 
 for school buildings, or has its value yet been recognized 
 by many owners of factory buildings, workrooms, etc. 
 The prismatic glass is simply window glass cast with hori- 
 zontal prisms on the outer surface, which reflects the light 
 
DAYLIGHT ILLUMINATION 
 
 123 
 
 FiQ. 46. — Showing the use of prism glass to deflect the light in a horizontal direction. 
 
124 
 
 HYGIENE OF THE EYE 
 
 from the sky into the building. These prisms can be cast 
 at various angles, which throw the light in a particular 
 direction, depending upon the angle of its reflecting sur- 
 face to the sky (Figs. 46 and 47) . 
 
 The prismatic glass is made with prisms set at diff er- 
 
 3K 
 
 60' 
 
 y^ 
 
 y 
 
 
 S5X 
 
 // 
 
 /: / 
 
 (Ky Kxrc do* 
 
 o 
 o. 
 a- 
 
 
 c 
 
 
 
 <r\ 
 
 c 
 
 Fig. 47. — Illustrating the uses of prism glass with different angles of reflection. 
 
 ent angles, so that by the proper employment of glass with 
 differing angles, the light can be thrown to almost any 
 section of the upper part of the room. Prismatic glass 
 has the great advantage of being able to make available a 
 light from the sky, which is not possible without its use, 
 and it has a particular advantage in buildings which do not 
 
DAYLIGHT ILLUMINATION 125 
 
 receive their light from points near the horizon. If school 
 windows with northern exposures were required to have 
 the upper part of the sash filled with prismatic glass, it 
 would go far towards overcoming the disadvantage of this 
 orientation. 
 
 What is true of school buildings is also true of manu- 
 facturing buildings, although in certain lines of work where 
 shadows are inadmissible and where the intensity of the 
 light should not vary greatly during the working hours, 
 southern exposures are not permissible. In textile trades 
 in the matching of color values, in engraving, in artists' 
 studios, etc., and in all work where close vision is required, 
 the northern light is to be preferred, and where conditions 
 permit, this form of lighting can be accomplished by means 
 of saw-tooth skylights, in which the vertical glass surface 
 of the skylight is only open to the light from the north. 
 
 In many buildings where north light is not required, 
 the employment of skylights which have either a glass 
 deck or a solid deck with glass side lights, permits a more 
 equitable lighting of such rooms than can be obtained by 
 windows alone. Such methods of lighting have utilitarian 
 as well as architectural and aesthetic values. The simula- 
 tion of skylights in the ceiling of rooms, by means of arti- 
 ficial lights placed behind the diffusing sash, has been 
 successfully carried out in a number of rooms, such as 
 auditoriums, restaurants, etc., where the structural condi- 
 tions prohibited the employment of actual skylights. By 
 this means it is quite possible to give an underground room 
 all the appearance and atmosphere it would have, were its 
 roof opening to the sky. The Auditorium of the Asso- 
 ciated Engineering Society's Building, and the Orangery 
 of the Hotel Astor, in New York, are excellent examples 
 of this method of artificial skylighting. 
 
126 HYGIENE OF THE EYE 
 
 A considerable amount of direct light from the sky in 
 top floors of buildings is not utilized, owing to a prevalent 
 idea that a skylight cannot be made watertight. It is quite 
 possible to make any skylight that is properly constructed 
 and designed as tight as a solid roof, and a knowledge of 
 this fact should lead to a larger use of skylights than is now 
 the custom. There is no light equal to daylight, and every 
 legitimate means of extending its use indoors should be 
 utilized. 
 
 Another method of introducing natural light into dark 
 interiors is by the employment of prismatic vault lights 
 set in the surface of pavements. With glass reflecting 
 prisms properly placed, it is quite possible to reflect a con- 
 siderable amount of light from the sky to the ceilings of 
 basement rooms. 
 
 Proper illumination, both natural and artificial, has a 
 distinct commercial value on the output of work. In the 
 first report of the Departmental Committee on " Lighting 
 in Factories and Workshops," recently published in Lon- 
 don, some startling facts have been shown. For instance, 
 in testing the strength of the illumination in a workshop on 
 a well-lighted top floor, they found it was only 2 to 10 
 per cent, of the direct sunshine. In other words, workers, 
 in what would ordinarily be considered favorable condi- 
 tions, were losing 90 to 98 per cent, of the light. No won- 
 der that eye-strain and headaches are common among 
 indoor workers. It has been found, as a matter of fact, 
 that spectacles are much more commonly used among them 
 than among outdoor workers. Much can be done by the 
 improvements in the system of lighting. In one case, the 
 Committee found, on investigating a workshop where a 
 better system of lighting had been installed, that the pro- 
 duction had increased 10 per cent. 
 
CHAPTER IX 
 
 DISEASES OF THE CONJUNCTIVA 
 
 In the chapter dealing with the anatomy of the eye, the 
 conjunctiva was described as the delicate membrane which 
 lined the lids and covered the exposed portion of the eye- 
 ball, and was continuous, through the medium of the lachry- 
 mal passages, with a similar membrane in the nose. This 
 membrane contains many glands, rich in mucus, and a 
 plentiful supply of blood-vessels and nerves. When the lids 
 are closed, it forms a closed sac, and at all times offers a 
 favorable soil for the growth and development of micro- 
 organisms, the germs of disease. These microorganisms 
 are very minute vegetable organisms, which multiply with 
 great rapidity when they are placed under conditions favor- 
 able to their growth, and in the process of growing, destroy 
 the tissues in w^hich they develop. 
 
 In the case of the conjunctiva, they excite a secretion 
 which varies in character according to the intensity of the 
 inflammation occasioned by the bacillus or microorganism, 
 the product of the most virulent being a thick yellow dis- 
 charge termed pus, while the milder growths occasion a 
 thick mucoid or catarrhal exudation. The discharges from 
 the conjunctiva excited by these small agents are all con- 
 tagious, that is to say, they have the power of exciting a 
 similar inflammation in other eyes with which they maj^ 
 come in contact. The degree of the contagiousness is in 
 direct ratio with the virulence of the organism, being great- 
 est in purulent conjunctivitis and least in the catarrhal 
 forms. The term conjunctivitis is applied to all forms of 
 
 127 
 
128 HYGIENE OF THE EYE 
 
 inflammations of the conjunctiva, the particular varieties 
 being designated by a descriptive prefix, such as catarrhal 
 conjunctivitis, purulent conjunctivitis, etc. 
 
 Infection of the eyes of an individual from those of an- 
 other is occasioned by the conveyance of the germs, either 
 by bringing them from the affected eye into direct contact 
 with the unaffected eye through the medium of soiled 
 fingers or articles contaminated by the discharge from the 
 the former, or through the medium of the air, the wind 
 blowing the dried secretion from diseased into healthy eyes. 
 The former mode of infection obtains in the purulent form, 
 the latter in the milder or catarrhal forms. This peculi- 
 arity of the manner of distribution of the disease accounts 
 for the epidemic form which is frequently observed in 
 connection with the catarrhal forms of conjunctivitis, while 
 the more virulent types, unless propagated under unusu- 
 ally bad hygienic conditions such as sometimes obtain in 
 trachoma cases, generally occur singly. 
 
 Not all forms of conjunctivitis are dependent upon 
 germ activity. Uncorrected error of refraction is a potent 
 cause of a mild form of conjunctivitis, the inflammation in 
 the mucous membrane resisting all local treatment until 
 the proper correcting lenses have been prescribed. Simple 
 catarrhal conditions may also accompany inflammation of 
 surrounding structures and may be excited by the action 
 of irritants, such as small foreign bodies, the exposure of 
 the eyes to high winds, smoke, certain fumes and gases, and 
 heat and light rays. Workers over furnaces in iron 
 foundries frequently have injected conjunctivae, and ex- 
 posure to the sun rays or snow fields may excite a most 
 distressing conjunctivitis, unless the eyes be properly cor- 
 rected by some form of protecting glasses, containing lenses 
 
DISEASES OF THE CONJUNCTIVA 129 
 
 properly colored to neutralize the irritating effect of the 
 ultra-violet rays. Greenish and amber tinted lenses have 
 been found to be best for this purpose. The conjunc- 
 tiva may also be inflamed in consequence of certain diseases 
 of the general system, which germinate poisonous prod- 
 ucts which may eliminate themselves from the broad ex- 
 panse of the conjunctival mucous membrane. 
 
 Diseases of the conjunctiva, therefore, are among the 
 most common affecting the eye, and occur under a variety 
 of forms. It would be apart from the purpose of this book 
 to describe all, though a detailed account must be given of 
 several, as they are of paramount importance, and their 
 danger and frequency demand a fuller knowledge of them 
 by the laity. 
 
 Purulent Conjunctivitis of Infants — ^^Ophthal- 
 MiA Neonatorum. — Under these names are included all 
 inflammatory conditions of the conjunctiva of the new- 
 born babe, conditions which by reason of their malignancy 
 are responsible for at least 25 per cent, of the blindness 
 throughout the world. As it will presently appear that 
 this disease is almost always preventable and its frequency 
 due to ignorance and incompetency, which can only be com- 
 bated by a campaign of instruction, the consideration of 
 this subject will be treated at length, not only as regards 
 its recognition and prevention, but also as to its treatment. 
 
 This inflammation of the conjunctiva appears usually 
 on or before the fifth day after birth, as a redness and 
 swelling of the lids, and with an attendant discharge of 
 watery fluid from between the lids. The redness and swell- 
 ing of the lids rapidly increase and the discharge becomes 
 thicker and more copious, so that on the third or fourth 
 day after the appearance of the inflammation the lids are 
 
130 
 
 HYGIENE OF THE EYE 
 
 so swollen that they can be forced apart only with diffi- 
 culty, while the lids and the eyeball are covered with a 
 thick creamy pus (Fig. 48). If untreated, the intensity 
 of the inflammation irritates the cornea and this membrane 
 loses its transparency and becomes infiltrated with pus. 
 After a time, the cornea, weakened by its ulceration, per- 
 forates, and the fluids within the eye and often the lens 
 escape into the conjunctival sac and the eye is lost (Fig. 
 
 Pig. 48. — Negro baby with ophthalmia neonatorum. 
 
 49 ) . Although but one eye is usually afl'ected primarily, 
 unless the greatest care is exercised the other soon becomes 
 similarly involved. After the disease has run an acute 
 course of several weeks, the inflammatorj^ symptoms gradu- 
 ally subside, and after a time the lids are opened again, but 
 over sightless and hideous stumps, instead of seeing eyes 
 (Fig. 50) . As years go by, not infrequently, the sightless 
 globes stretch and the transparency of the cornea being 
 
DISEASES OF THE CONJUNCTIVA 
 
 131 
 
 replaced by glistening white scar tissue, the deformed and 
 sightless orbs, rotated by their poor little possessors from 
 
 K... 
 
 Fig. 49. — Corneal abscess with perforation. 
 
 side to side in their search for vision, form as striking and 
 distressing a picture as may be found in nature. 
 
 The disease is very contagious, and if the discharge 
 enter the eyes of an adult or older child, an inflammation 
 
 Fig. 50. — Opaque cornea after ophthalmia neonatorum. 
 
 of even greater seriousness is excited than that which pri- 
 marily affected the eyes of the new-born babe. 
 
 The cause of this distressing disease is the infection of 
 
132 HYGIENE OF THE EYE 
 
 the eyes of the child during the passage of the head through 
 the birth canal of an infected mother, or by the entrance 
 of the germs into the eyes shortly after birth, in conse- 
 quence of carelessness upon the part of attending phy- 
 sician, midwife, or nurse. The germ usually responsible 
 is the pus of gonorrhoea, a disease which affects the genital 
 organs of both men and women, and is readily transmis- 
 sible from the one to the other. The history obtainable in 
 many cases is that of the mother infected by her husband, 
 who, though once diseased with gonorrhoea, had dared to 
 marry, as the absence of urethral discharge had encour- 
 aged the idea that the affection was cured or had worn 
 itself out. After marriage, the disease communicated to 
 the wife in a mild form gives no indication of its existence 
 until the child is born and the germs entering the closed 
 sac of the conjunctiva propagate and destroy. Society 
 should demand that every man who has suffered from 
 gonorrhoea should debar himself from matrimony until he 
 has been assured by expert examination that he is free 
 from infection. 
 
 Not all cases of inflamed eyes after birth, however, are 
 due to venereal diseases, for germs of a totally different 
 and less virulent nature may gain access to the conjunctiva 
 and may occasion much the same symptoms as have been 
 described.^ It is most unfair, therefore, to attach an op- 
 probrium to the parents of all children with ophthalmia, 
 and the finger of scorn has been shaken too often in the 
 face of a perfectly innocent and virtuous father. 
 
 As it is sometimes difficult to discriminate rapidly and 
 
 ^ It has been estimated! that gonococcus infection gives rise 
 to about 60 per cent, of all cases of ophthalmia neonatorum. The 
 pneumococcus is responsible for about 10 per cent. 
 
DISEASES OF THE CONJUNCTIVA 133 
 
 easily between the milder and, so to speak, innocent type 
 and the malignant form, it is customary^ to treat all cases 
 from the beginning as though they were of venereal origin, 
 for so rapid and virulent is the course of the conjunctivitis 
 that unless proper and prompt treatment is applied, the 
 eye is lost. Xo time can be wasted. Xo chances run. 
 
 In 1881, Crede, a well-known Belgian physician, found 
 that if a 2 per cent, solution of nitrate of silver be dropped 
 into the eye of a child directly after birth, the pus germ 
 producing ophthalmia neonatorum could be killed and the 
 development of the disease prevented. This discovery has 
 been of vital importance, and many a child has been saved 
 from blindness by this simple procedure. Statistics show, 
 for example, that in certain classes of cases the disease de- 
 veloped in 10 per cent, of children in whom the silver solu- 
 tion had not been used, and in but 0.17 per cent, after 
 Crede's procedure had been applied. 
 
 To eradicate the disease, it would appear therefore only 
 necessary that the silver solution should be used in the eyes 
 of all babies directly after birth. This apparently simple 
 problem is not, however, so easy of solution, and there are 
 various factors which experience has shown must be taken 
 into consideration before urging the adoption of Crede's 
 method in all cases. In the first place, the silver solution, 
 even when properly applied, may excite considerable irri- 
 tation of the mucous membrane of the eye, which, unless 
 treated, might result in some permanent danger to what 
 might otherwise have been an unaffected eye. Again, the 
 hands instilling the drops may be clumsy or unclean, and 
 healthy eyes ruined in consequence. ^lany ophthalmol- 
 ogists, therefore, who have cared for eyes damaged in this 
 way, are loath to urge the passage of laws making the 
 
134 HYGIENE OF THE EYE 
 
 application of the Crede method obligatory in all cases, 
 and incline to the recommendation of its use in all suspected 
 cases and in all hospitals and institutions where the danger 
 of infection is greater than in certain classes of private 
 work. Yet it is very necessary that each State should have 
 stringent laws and a well-defined and practical policy aim- 
 ing at the control and actual elimination of ophthalmia 
 neonatorum. Briefly outlined this should be as follows: 
 1. Every birth should be reported to the Bureau of Health 
 within 24 hours. 2. Every case of inflamed eyes should be 
 reported to the Bureau of Health within 4 hours. 3. The 
 provision by the Bureau of Health for skilled ophthalmic 
 treatment of every reported case within two hours after 
 the Bureau has been notified of the existence of the ocular 
 disease, by the attending obstetrician or midwife. The 
 bureau must exercise control over the treatment of the case 
 until the ophthalmologist in attendance reports the eyes 
 •entirely free from inflammation. When proper home 
 treatment is for any reason undesirable or impossible, all 
 the hospitals receiving financial aid from the common- 
 wealth must be ready to provide indoor treatment for the 
 child and mother as well if the need arise. 4. Solutions of 
 silver nitrate for prevention should be distributed free 
 upon request, and printed matter describing the dangers 
 of ophthalmia neonatorum, with hints as to cleanliness 
 itself, properly couched for the comprehension of the laity 
 and printed in various languages, should be freely cir- 
 culated. 5. The midwives who have charge of perhaps 
 nearly one-half of the births in the United States should 
 be licensed, and their recognition given only after they 
 have received sufficient education to warrant their attend- 
 ance of a woman in labor. They should receive thorough 
 
DISEASES OF THE CONJUNCTIVA 
 
 135 
 
 training in the washing out of a child's eyes and the in- 
 stillation of the silver solution (Figs. 51, 52, and 53). 
 
 The following directions to mothers, midwives, and 
 nurses are freely distributed by the Department of Health 
 of one of the great commonwealths of this country, and 
 
 FiQ. 51. — A good midwife cares for the baby's eyes. Careless and untrained midwives are 
 responsible for much infantile blindness. 
 
 are so clearly expressed and graphic that they are printed 
 in full. 
 
 " This disease is always due to an infection entering the 
 eyes of the baby at the time of or shortl}^ after birth. It 
 may be prevented almost always by proper care and early 
 and correct treatment. 
 
 " If precautions are not taken, and the disease de- 
 
136 
 
 HYGIENE OF THE EYE 
 
 velops and runs its course unchecked, the sight is totally 
 destroyed, often within a fortnight. 
 
 " For All Mothers. — Pleasures to he Taken hy the 
 
 a%4^ 
 
 Fig. 52. — -Nurse applying drops to baby's eyes 
 
 Mother During Pregnancy. — All women during preg- 
 nancy should be instructed as follows: Daily external 
 cleansing should be thoroughly performed with soap and 
 water and a clean wash cloth. Should the pregnant woman 
 
DISEASES OF THE CONJUNCTIVA 
 
 137 
 
 have any irritating discharges, or even profuse white dis- 
 charge, she should be instructed to immediately consult her 
 physician or the nearest dispensary. 
 
 "For All Children ( Prevextiox ) » — Care that 
 Should he Given to the Child at Birth to Prevent Oph- 
 
 Vin. .>i. — New-born baby being treated in hospital for babies' sore e> o^ 
 
 thalmia Neonatorum. — Inmiediately after the delivery of 
 the head, before the delivery of the body, the eyelids should 
 be carefully cleaned by means of absorbent cotton or a 
 soft linen cloth and dipped into warm water that has l>een 
 boiled or boric acid (saturated) solution. A separate cloth 
 
138 HYGIENE OF THE EYE 
 
 should be used for each eye, and the lids washed, from the 
 nose outward, free from all mucus, blood or meconium. 
 All wipes should be burned after using. No opening of 
 the lids should be attempted. At this time also the lips 
 and nose should be in like manner wiped free of mucus, and 
 the little finger, wrapped with a piece of moist linen, should 
 be passed into the child's mouth and any accumulated 
 mucus removed by an outward sweep of the finger. As 
 soon after birth as possible the eyelids should be again 
 wiped clean of mucus, and two drops of a 1 per cent, solu- 
 tion of nitrate of silver should be dropped into each eye. 
 One application only of the silver solution should be made, 
 and ordinarily no further attention should be given the 
 eyes for several hours. 
 
 " Each time that the child is bathed, the eyes should be 
 first wiped clean, as above described, with the boric acid 
 solution. The hands of the person charged with the care 
 of the child must be washed with soap and dried with a 
 clean towel before the eyes of the child are touched. Every- 
 thing that is brought near the eyes of the child must be, in 
 every instance, absolutely clean. 
 
 " The cotton that is used on the eyes of the child must, 
 in every instance, be immediately burned after it is used. 
 The water, towels, old linen, and the cotton that have been 
 used on the mother must, under no circumstances, be ap- 
 plied to the child. The air of the bedroom must be kept as 
 pure as possible, and the linen should never be dried in the 
 sick room. 
 
 '' What Must be Done When Inflammation of the Eyes 
 Appears. — ^When the lids become red and swollen, and are 
 gummed along their borders, and when mattery discharge 
 is mixed with the tears as the child sleeps or cries an oculist 
 
DISEASES OF THE CONJUNCTIVA 139 
 
 or a physician should be called immediately, or the child 
 taken to the nearest dispensary. Each hour of delay adds 
 to the danger. While waiting bathe the eyes of the child 
 every half hour with pledgets of cotton dipped in a solu- 
 tion of boric acid. Open the lids wide and allow the 
 solution, which should be warm, to flood the eyes and wash 
 out any matter which may have gathered there. 
 
 " The child should not be fondled and nothing which 
 has been used about the eyes or face should be used for 
 any other purpose. All of those in the home should be 
 warned of the danger of catching the disease by getting 
 the matter into. their own eyes. Do not listen to those who 
 say it will amount to nothing, or to those who say to bathe 
 the eyes of the child with the mother's milk (the milk is a 
 means of spreading the germs of this disease). Such ad- 
 vice is bad; the delay may result in blindness." 
 
 The prognosis in ophthalmia neonatorum depends en- 
 tirely upon the progress which the disease has attained when 
 the eyes come under the care of the ophthalmologist, for 
 if the proper treatment be instituted within the first few 
 days, before corneal involvement has occurred, the sight 
 can, as a rule, be saved. If the cornea shows signs of ulcera- 
 tion when expert medical supervision is sought, the out- 
 look is much more serious and more or less loss of visual 
 acuity is sure to follow. 
 
 Purulent Conjunctivitis of Adults. — Gonorrhoea 
 may also affect the eyes of adults, the pus germ being con- 
 veyed to the eyes, as a rule, directly from the affected 
 genitalia by soiled fingers. Others may also be infected 
 by the germs being carried to their eyes by towels, hand- 
 kerchiefs, bed linen, already contaminated by a person 
 with gonorrhoea. The inflammation set up in the conjunc- 
 
140 HYGIENE OF THE EYE 
 
 tiva under such conditions is most intense, giving rise to 
 great swelling of the lids and of the mucous membrane. 
 In consequence of the intensity of the inflammation, the 
 cornea is involved, and perforation of this membrane, with 
 loss of the eye, may occur within four or five days after the 
 initial symptoms have manifested themselves. If but one 
 eye is affected, the other usually follows unless the greatest 
 care is exercised and the most vigorous treatment instituted. 
 
 All attempts to successfully treat such cases as am- 
 bulants are futile, and the author cannot remember to have 
 seen one eye saved, unless the patient was confined to bed 
 from the very first and received constant and skilful treat- 
 ment until the danger had passed. 
 
 The discharge from the conjunctiva, at first merely 
 streaked with mucus, becomes thick and copious and is ex- 
 tremely contagious. Attendants upon such cases must 
 exercise the greatest care to avoid infection. All cotton or 
 lint dressings should be burned and the hands of surgeons 
 and nurses carefully sterilized after each application of 
 drugs or dressings. If but one eye is affected, it is usually 
 customary to protect the sound eye by means of a watch 
 crystal plastered into position before the eye by adhesive 
 plaster. This device serves not only as a protection, but 
 also enables the surgeon to inspect the eye and permits 
 the patient to have some view of his surroundings. 
 
 So acute is the inflammation and so virulent its prog- 
 ress that it has been estimated that but 50 per cent, of eyes 
 so infected recover. The necessit}^ of prompt and active 
 treatment in gonorrhoeal ophthalmia of adults must there- 
 fore be apparent, and the strictest mandate to all those 
 affected with sronorrhoea to observe the greatest caution 
 
DISEASES OF THE CONJUNCTIVA 141 
 
 in all things and to seek medical aid on the first suspicion 
 of an inflamed eye seems reasonable to comply with. 
 
 Metastatic Gonorrhceal Ophthalmia. — In addi- 
 tion to the direct invasion of the conjunctiva by means of 
 soiled fingers, etc., the gonorrhoeal poison may also enter 
 the eye indirectly, through the medium of the blood. 
 Gonorrhoea does not always remain a localized disease of 
 the genital organs, but in certain cases, especially those who 
 are gouty or rheumatic, and those who have suffered from 
 repeated attacks of the disease, the germs may enter the 
 blood and involve other parts of the body. The joints 
 especially show a marked predilection to participate in this 
 form of general blood poisoning, and under the form of a 
 general rheumatic infection, inflammatory conditions arise 
 in them which are most persistent and frequently cripple 
 the patient for life. 
 
 Either as a part of this rheumatic process or partici- 
 pating in a general blood infection without articular in- 
 volvement, the eye tissues not rarely show involvement ; the 
 iris, conjunctiva and cornea may all be inflamed, with a 
 frequency of involvement of these tissues in the order 
 named. 
 
 These transmitted or " metastatic " inflammations, as 
 they are called, are extremeh^ serious when the iris is in- 
 volved, but less so in their corneal and conjunctival mani- 
 festations. ^Metastatic gonorrhoeal conjunctivitis is much 
 less dangerous to sight than the conjunctivitis caused by 
 direct infection of the gonorrhoea germ. It usually takes 
 the form of a persistent attack of inflammation of the 
 membrane, with considerable swelling of the lids and con- 
 junctiva and with a more or less copious mucopurulent 
 discharge. Local treatment is ineffective, the inflamma- 
 
142 HYGIENE OF THE EYE 
 
 tion yielding only after the poisonous nature of the internal 
 secretion and the blood have been improved, and by treat- 
 ment directed to the primary source of the inflammation. 
 
 Women are rarely affected by metastatic gonorrhoea, 
 but a form of purulent conjunctivitis is sometimes ob- 
 served in young girls the subjects of vaginitis, the gono- 
 cocci present in the discharge being conveyed to the eyes 
 by the fingers or from soiled linen, etc. The resultant con- 
 junctivitis is often quite violent, though rarely so severe 
 as the gonorrhoeal conjunctivitis of adults. At times, in 
 consequence of the contagious nature of the vaginitis, the 
 genital affection in association with the conjunctivitis may 
 assume an epidemic form in hospitals, schools and asylums. 
 If properly treated, such cases usually recover without 
 impairment of vision. 
 
 Trachoma — Granular Conjunctivitis. — Next in 
 importance to purulent conjunctivitis caused by the germ 
 of gonorrhoea is granular conjunctivitis, or, as it is gen- 
 erally termed, trachoma. This disease of the conjunctiva 
 runs a prolonged course, affecting all parts of the mucous 
 membrane, and is attended by the development of so-called 
 granulations, or trachoma bodies, in consequence of which 
 the conjunctiva loses its smooth surface and becomes rough- 
 ened (trachoma, from the Greek " traxus," meaning 
 rough) (Fig. 54). Later the granulations disintegrate 
 and form scar tissue, causing distortion of the lids and 
 lashes. In addition to the changes in the lids, vasculariza- 
 tion and ulceration of the cornea follow, giving rise to 
 marked impairment of vision and in some cases to total 
 loss of sight. In most cases the disease is ushered in with 
 symptoms similar to those of purulent conjunctivitis, the 
 lids being swollen and inflamed and bathed in a copious 
 
DISEASES OF THE CONJUNCTIVA 
 
 143 
 
 discharge containing an admixture of mucus and pus ( Fig. 
 55 ) . This acute stage may last for weeks or months, finally 
 passing into a milder one of constant irritation and dis- 
 
 
 Fig. 54. — -A typical case of advanced tra- 
 choma ' showing numerous granulations. Lids 
 hypertrophied. 
 
 Fig. 55. — Kentucky girl suffering from 
 trachoma, holding her eyes open with 
 forefinger and thumb. 
 
 charge. In other cases the advent of the disease is in- 
 sidious (Figs. 5% and 57), the trachoma bodies developing 
 with but little accompanying inflammation of the conjunc- 
 
 FiG. 56. — Trachoma. Cicatrization 
 marked. 
 
 well 
 
 Fig. 57. — Trachoma. Cicatrization almost 
 complete. 
 
 tiva. The lids, however, are thickened and droop, giving 
 a characteristic sleepy appearance to eyes so aflTected. 
 Upon the eversion of the lids in many of these less acute 
 
144 
 
 HYGIENE OF THE EYE 
 
 cases, the granulations may at first escape the attention 
 of the observer, being hidden deep under the fold of con- 
 junctiva of the upper lid. The course of the disease is 
 essentially a chronic one, remissions and exacerbations 
 being excited by the slightest extraneous causes, as well 
 as by certain conditions of the system. Unless recog- 
 
 FiG. 58. — The operation of rolling or expression. 
 
 nized in its earliest stages and a cure assured by treatment 
 (Fig. 58) directed over a long period, trachoma is un- 
 curable, and all of the later forms of treatment are merely 
 palliative. 
 
 Trachoma is an ancient disease, reference to it being 
 found in the earliest literature. Originating in the Far 
 
DISEASES OF THE CONJUNCTIVA 
 
 145 
 
 East, it was probably carried westward along the great 
 caravan routes. Although doubtless present in Europe 
 before that time, the spread of the disease over that coun- 
 try is generally attributed to the return of the Napoleonic 
 soldiers from Egypt to Europe, many of the troops 
 
 Fig. 59. — Man and child using common towel. Trachoma and other intectious eye diseases 
 
 contracted in this way. 
 
 having contracted the disease in Egypt from the native 
 population. 
 
 Trachoma is very contagious, the infective material 
 contained in the discharge being conveyed from eye to eye 
 by dirty fingers, soiled towels (Fig. 59) and linen, and 
 wash basins contaminated with the disease, etc. Trachoma 
 
 10 
 
146 HYGIENE OF THE EYE 
 
 is a disease of poverty, the conditions under which the very 
 poor live fostering its development and spread. The mass- 
 ing together of large numbers of people, children or 
 adults, in badly ventilated houses, without the possibil- 
 ity of maintaining personal cleanliness, is responsible 
 for its rapid spread under such conditions. Hence it is 
 that the Jews, by reason of their abject condition in so 
 many parts of the world, but particularly in Russia and 
 Poland, are so frequently affected. The disease is also 
 common in Ireland and almost all the Southern Euro- 
 pean nations. It is estimated that 90 per cent, of the 
 population of Egypt is afflicted with the disease. It 
 would appear that the negro race is practically immune 
 from trachoma. 
 
 Unfortunately, the disease is not uncommon in the 
 United States, having been introduced largely by infected 
 immigrants. Indeed, in 1897, the government found the 
 spread of the disease from this source to be so great that a 
 law was passed requiring the examination of the eyes of 
 all immigrants and making mandatory the deportation of 
 aliens so afflicted. Unfortunately, however, the bars were 
 put up too late, for the disease had already gained con- 
 siderable headway in certain parts of the country. The 
 Jewish peddler and tailor and the Italian and Slavish 
 laborer in mines and mills spread the disease, so that there 
 is no part of the country where trachoma cannot be found. 
 The greater number of cases from foreign infection are 
 found, however, in the large maritime and manufacturing 
 and mining sections. 
 
 In addition to its spread among the foreign popula- 
 tion, trachoma is also common among the American In- 
 dians and the Appalachian Highlanders in the mountain 
 
DISEASES OF THE CONJUNCTIVA 147 
 
 sections of Kentucky, Virginia, and West Virginia. There 
 is evidence that the Indians and these mountaineers must 
 have contracted the disease many years ago; just how, will 
 doubtless always remain undetermined. Statistics show 
 that of the 323,000 Indians in our own country fully 20 
 per cent., or nearly 65,000, are infected. In Kentucky 
 there are 33,000 cases. 
 
 One of the greatest problems connected with trachoma 
 is its occurrence and spread among the school children of 
 our country. The children of infected foreigners attend 
 the same schools as the children of the native population, 
 and come in intimate contact with them in studies and 
 games, handling the same objects, and, with shame be it 
 said, using at times the same roller towel, one of the most 
 dangerous methods of transmission of this as well as other 
 diseases. 
 
 In view of these facts, it is apparent that in addition 
 to the suffering wrought by trachoma, the visual impair- 
 ment resulting from it presents a problem of great economic 
 significance. ]\Iany are blinded in consequence and become 
 an absolute drag upon the State, while the earning capacity 
 of others affected with the disease is at least one-fourth of 
 that of ordinary individuals. 
 
 The government has done much in recent years to abate 
 the evil, for, in addition to the stringent examination of 
 immigrants and the exclusion of all affected with trachoma, 
 the Public Health Service has been active in its efforts to 
 eradicate the disease among the Indians and is aiding some 
 of the States in their campaign against it. Already five 
 completely equipped trachoma hospitals have been erected 
 in the heart of the most seriously infected regions in 
 Kentucky. 
 
148 HYGIENE OF THE EYE 
 
 The prevention of trachoma, however, demands a more 
 thorough knowledge by the public of its nature and dan- 
 ger, and an improvement in the industrial and housing 
 conditions of the poor. The report of every case to the 
 proper health authorities must be mandatory, and each 
 State must provide proper facilities for the isolation and 
 treatment of all infected individuals until the danger of 
 contagion is past. The eyes of all school children must be 
 examined by properly trained individuals periodically, and 
 arrangement should be made for the inspection of the eyes 
 of all groups of adults, in whom there is likelihood of the 
 existence of trachoma. 
 
 The problem of controlling the disease among children 
 is best met by their isolation in hospital schools, until they 
 are absolutely cured of the disease. In order that this may 
 be accomplished, a year or more in residence is often neces- 
 sary, so that it is desirable to add to their ocular treatment 
 instruction in elemental educational subjects, so that the 
 period of their confinement for medical treatment may en- 
 tail no period of mental inactivity. The care of adults 
 affected with trachoma is much more difficult of solution, 
 for it is manifestly impossible to isolate the beads of 
 families, their sources of support, for any considerable 
 time. In establishments employing large numbers of work- 
 men, it is often possible to group all trachoma subjects to- 
 gether and to keep them under constant medical supervi- 
 sion, but in factories and mines employing fewer men this 
 is not feasible, and the makeshift of medical care while the 
 disease is absolutely disabling and the continuance of work 
 after the ocular condition has been improved under social 
 service or some other form of supervision, must be adopted. 
 Placards of a warning and instructive nature concerning 
 
DISEASES OF THE CONJUNCTIVA 149 
 
 the danger of the disease and the best means of avoiding 
 it should be hung in conspicuous places, and friendly ad- 
 vice and counsel given to the workers in their own lan- 
 guage by some trustworthy and interested person. The 
 following is an example of what such placards should 
 contain : 
 
 '' How to Avoid Contracting Trachoma, — Keep in good 
 physical condition. 
 
 Have large windows in your homes, which will admit 
 plenty of fresh air and sunshine. 
 
 Sleep with your windows open, even in winter, and keep 
 the room well aired where you live and study. 
 
 Wash your face and hands several times a day and keep 
 the finger-nails clean. 
 
 Never touch your face with your hands, unless they are 
 absolutely clean. 
 
 Do not use the family towel, especially in homes where 
 there are cases of trachoma. 
 
 Have your own towel and handkerchief, and don't let 
 any one else use them. 
 
 Boil your handkerchiefs before adding them to the 
 wash. 
 
 Do not allow your clothing or bedclothes to become 
 soiled with the discharges (pus) from your eyes. 
 
 When your eyes are discharging pus collect the dis- 
 charges on cloths which can be burned, and stay away from 
 other members of your family as much as possible. 
 
 Always make sure that the wash basin is clean before 
 using it. 
 
 Do not sleep with persons having sore eyes, nor use 
 bedclothes that have been used bv them. 
 
150 HYGIENE OF THE EYE 
 
 Do not wear the clothing of others, nor use then* eating 
 utensils without previously cleaning. 
 
 Advise any one with sore eyes to have them treated at 
 once. 
 
 If the eyes become inflamed, apply at once for treat- 
 ment to the nearest hospital, dispensary or to your own 
 physician. 
 
 Follow the directions of the doctors and nurses as to 
 treatment and prevention." 
 
 Although trachoma in its advanced stages is easy of 
 detection, the determination of its existence in the earliest 
 stages is often difficult and can only be made by physicians 
 who have received special ophthalmic training. A number 
 of diseases of the conjunctiva may be mistaken for it, and 
 as these are harmless, the insistence upon the rigorous quar- 
 antine just mentioned would entail unnecessary and un- 
 just hardship upon the individuals whose eyes are so 
 affected. The disease of the conjunctiva with which 
 trachoma is usually confused is follicular conjunctivitis, 
 for in this disease the conjunctiva is similarly studded with 
 numerous granules or follicles. This condition, which oc- 
 curs for the most part in underfed and so-called " scrof- 
 ulous " children, may persist for months, without giving 
 rise to any secretion from the conjunctiva or corneal in- 
 volvement. It frequently disappears without leaving a 
 trace under better hygienic conditions, and at no time in 
 its course does it possess any contagious qualities. 
 
 It is apparent, therefore, that the examination of eyes 
 for the detection of trachoma, whether it be under the 
 auspices of the government in its inspection of immigi^ants, 
 or of school authorities, is valueless unless made by thor- 
 
DISEASES OF THE CONJUNCTIVA 151 
 
 oughly trained medical graduates. All other examinations 
 are misleading and valueless.^ 
 
 Milder Forms of Conjunctivitis. — Acute Catarrhal 
 Conjunctivitis; Pink Eye, — This form of conjunctivitis, 
 occurring usually in the spring and autumn, when the 
 weather is changeable and the winds high, is the most com- 
 mon variety of conjunctivitis in the United States. It is 
 very contagious, the contagion-bearer, the Koch- Weeks 
 bacillus, the specific organism which causes the disease, being 
 contained in the copious discharge from the conjunctiva, 
 and communicated to the eyes of others not affected in the 
 manner described in connection with the two preceding con- 
 ditions. The inflammation, which at first occasions but a 
 slight redness of the lids and eyeball, and an increase in the 
 flow of tears, attains considerable severity by the third day, 
 the lids becoming markedly swollen and the discharge thick 
 and ropy. If but one eye is originally afl'ected, the other 
 soon follows. Ordinarily the inflammation runs its course 
 in about 10 to 14 days, the eyes making a complete re- 
 covery. Corneal ulceration occurs at times, however, .so 
 that the disease demands constant oversight and intelligent 
 treatment. One of the synonyms of the disease, viz., epi- 
 demic conjunctival catarrh, illustrates a pronounced ten- 
 dency of the disease, the inflammation frequently spread- 
 ing to all members of a household. Epidemics of the 
 disease are of not rare occurrence in schools, asylums and 
 similar institutions. 
 
 Subacute Conjunctivitis, — As indicated bv the name. 
 
 ^ For a more detailed account of trachoma from a popular 
 standpoint, the reader is referred to the excellent mionograph on 
 trachoma, published by the National Committee for the Preven- 
 tion of Blindness, 130 East 22nd St., New York. 
 
15!^ HYGIENE OE THE EYE 
 
 the inflammation in this form of conjunctivitis rareh^ as- 
 sumes the activity of that observed in the foregoing, but, 
 unless properly treated, often runs a protracted course. 
 The inflammation shows a predilection for the inner and 
 outer angles of the lids, in consequence of which the term 
 angular conjunctivitis is often applied to it. The secre- 
 tion is usually scanty and has a tendency to accumulate and 
 adhere to the inner angle of the eye. At times, however, 
 the discharge is copious and may assume a mucopurulent 
 type. Corneal ulcerations may also arise, threatening the 
 loss of the eye. The disease may occur at any season of the 
 year, and both eyes are generally affected. This form of 
 conjunctivitis has been found to be due to a definite organ- 
 ism, which was isolated and described by Morax and Axen- 
 feld, two distinguished foreign ophthalmologists. 
 
 Other forms of conjunctivitis due to other germs, such 
 as the pneumococcus and influenza bacillus, are also com- 
 monly met with. While the simpler forms of conjunc- 
 tivitis may often be cured by the removal of the cause and 
 the repeated cleansing of the eyes by boracic acid solutions 
 and the application of cold compresses, those due to specific 
 organisms demand skilled treatment. The milder forms 
 of conjunctivitis, though ordinarily benign processes of the 
 mucous membrane, may lead to the loss of the eye by 
 corneal ulceration. Furthermore, the recognition of the 
 microorganism causing the disease, and the application of 
 the proper treatment, will often so modify its course that 
 complete relief may be obtained in a few days from symp- 
 toms which might often be disabling for weeks. A few 
 applications of a solution containing zinc, to a conjunctiva 
 inflamed by the Morax- Axenfeld bacillus, will often alle- 
 viate as though by magic an inflammation which had resisted 
 all other forms of treatment for a very long time. 
 
DISEASES OF THE CONJUNCTIVA 153 
 
 Pinguecula and Pterygium. — By pinguecula is de- 
 noted a small yellowish elevation which forms on the eye- 
 ball in the free space between the lids and the inner margin 
 of the cornea and the caruncle, a small fleshy structure in 
 the inner corner of the eye. Ordinarily pinguecula is of no 
 significance, beyond the slight cosmetic blemish it entails. 
 At times, however, in persons exposed to the weather and 
 to the irritation of smoke, heat, etc., this little elevation may 
 attain considerable growth, expanding in fan-like fashion 
 to the margin of the cornea externally and to the fold of 
 
 ^IS 
 
 Fig. 60. — Pterygium. 
 
 mucous membrane observable at the inner angle of the eye 
 internally. When it has reached this development, the 
 term pterygium (Fig. 60) is assigned to it. Although at- 
 tached to the cornea and overlapping it, pterygium rarely 
 occasions more than slight visual disturbance by the astig- 
 matism which it evokes. Pseudo pterygium may, however, 
 develop in consequence of injuries and burns of the cornea, 
 and, when extensive, seriously jeopardize vision by involv- 
 ing that part of the cornea directly over the pupil. Ptery- 
 gium is amenable to operation, and may be removed by 
 excision or transplantation. 
 
CHAPTER X 
 
 DISEASES OF THE EYELIDS, LACHRYMAL AP- 
 PARATUS, CORNEA, IRIS AND VITREOUS 
 
 The outer surface of the eyelids may participate in 
 most of the diseases of the skin affecting the face, such as 
 eczema and erysipelas. The lids may also be the seat of 
 various benign and malignant tumors. Among the former 
 may be mentioned nasvi, or blood tumors, of different 
 sizes, and warts. Among the latter, epithelioma, or skin 
 cancer, is the most common. Removal of the benign 
 growths is usually recommended for cosmetic purposes, 
 but as it frequently happens that malignant growths ap- 
 pear at the site of warts and pimples which have been 
 irritated, the early extirpation of all such formations should 
 be advised, with a view to the avoidance of future trouble. 
 
 Though the skin cancers affecting the lids grow slowly, 
 their progress is constant, the deeper structures of the lids 
 and sublying tissues being also involved, so that in time 
 the entire structure of the lid is eaten away by the cancer, 
 robbing the eyeball of its protection. 
 
 In the early stages, various forms of electricity and 
 radium are very efficacious, but when extensive changes 
 have occurred, excision with the knife, conjoined with the 
 superposition of skin grafts or flaps of skin transposed 
 from the surrounding tissues, is necessitated. 
 
 Inflammation of the margin of the lids, or blepharitis 
 marginitis, as it is termed, is a common affection, occurring 
 in both children and adults who are in poor health or who 
 are suffering from uncorrected errors of refraction. The 
 
 154 
 
DISEASES OF THE EYELIDS 155 
 
 condition is essentially chronic and is attended by the for- 
 mation of crusts and ulcers on the margin of the lids. The 
 hair follicles become involved, and many of the eyelashes 
 are lost, often permanently. 
 
 In consequence of the participation of the hair follicles 
 in the process, suppuration of the cavity from which the 
 lashes grow may occur, and a stye or hordeolum appears. 
 These painful swellings may occasion a very marked cedema 
 of the tissues of the lid, and may give rise to considerable 
 disturbance of the general system before pointing and 
 spontaneous evacuation of their pussy contents. As pus- 
 producing microorganisms are always present, other glands 
 become infected and successive crops appear. 
 
 The cure of styes is often therefore difficult. The re- 
 moval of all predisposing causes must first be essayed. 
 Any tendency to constipation must be overcome by suitable 
 laxatives, digestive disturbances corrected, and tonics ad- 
 ministered. In obstinate cases, the hypodermic adminis- 
 tration of vaccines is often of value. Locally, the inflam- 
 mation of the lid margin, often primarily responsible for 
 the development of styes, should be allayed, by thorough 
 removal of all crusts with an alkaline wash and the appli- 
 cation of silver nitrate or of a salve composed of varying 
 strengths of the yellow oxide of mercury. The proprietary 
 salves advertised for the cure of styes generally contain 
 this ingredient. 
 
 Styes may often be aborted by applying strong solu- 
 tions of sulphate of zinc to the aif ected region, or by touch- 
 ing the infected hair follicle with carbolic acid. As contact 
 of either of these substances with the exterior of the eye 
 would be injurious, such applications should be made only 
 by competent medical practitioners. If abortive measures 
 
156 
 
 HYGIENE OF THE EYE 
 
 fail, incision with a sharp knife should be made the moment 
 pus forms. 
 
 The common practice of poulticing the eye with flax- 
 seed, tea leaves, etc., while giving relief to pain, on account 
 of the heat and moisture they afford, is injurious, on 
 account of the spread of the microorganisms which these 
 factors favor. Should poultices be applied, only those of 
 antiseptic properties, such as bichloride of mercury or witch 
 hazel, should be employed. 
 
 Chalazion (Fig. 61). — Another common and often 
 
 Fig. 61. — Chalazion. (Posey & Wright; Lea & Febiger.) 
 
 painful affection of the lids results from an enlargement 
 of one or more of the glands which aid in the lubrication 
 of the hair follicles. According to the number of glands 
 implicated, small swellings or chalazia form under the skin, 
 which disfigure the contour of the lid, and, often attaining 
 considerable size, press on the eyeball and interfere some- 
 what with vision. These growths may remain quiescent 
 for months and occasion no symptoms other than those just 
 referred to; in other cases, however, the contents of the 
 glands suppurate, giving rise to pain and considerable irri- 
 
DISEASES OF THE EYELIDS 157 
 
 tation of the conjunctiva. The relief of this condition 
 consists in early incision and evacuation of the contents of 
 the swelling with a small spoon-shaped instrument. 
 
 Displacement of the Eyelashes and Irregulari- 
 ties IN the Form and Position of the Eyelids. — Fre- 
 quently after burns and other injuries and long standing 
 disease of the conjunctiva and lids, the symmetry of the 
 row of lashes is interfered with, and the margins of the 
 lids no longer maintain their nice coaptation to the globe, 
 but roll either in or out. These conditions are present in 
 nearly all cases of trachoma, and the irritation of the eye- 
 ball by the misplaced lashes, the so-called " wild hairs," is 
 often one of the most distressing features of the disease. 
 Operative measures are usually necessary to correct the 
 evil and a large number of procedures have been devised to 
 restore the normal contour of the lids and to remove the 
 row^ of lashes from contact with the globe. 
 
 Ptosis. — Another disfiguring lid anomaly is produced 
 by a failure in innervation of the muscles which raise the 
 upper lids, in consequence of which the lids droop and par- 
 tially cover the eyeballs, imparting a drowsy appearance 
 to the patient, and necessitating the throwing back of the 
 head to obtain clear vision through the partially covered 
 pupils. This condition of ptosis (Fig. 62) , as it is termed, 
 may occur at any time of life, from paralysis of the nerves 
 supplying the elevators of the lids, or may be present at 
 birth. 
 
 ^ledicinal treatment may remedy the deformity due to 
 paralysis, but some form of operation which unites the lids 
 to the nervous supply of the muscles which raise the brow 
 is necessary for the correction of the congenital variety. 
 Congenital ptosis is often associated with an obliquity of 
 
158 HYGIENE OF THE EYE 
 
 the palpebral fissures and an abnormally broad fold of 
 skin at the base of the nose, imparting a Mongolian type 
 of features to those suffering from this rather uncommon 
 anomaly. 
 
 A painful, though fortunately a not very common, affec- 
 tion of the lids consists in the eruption of a number of 
 small blisters over one of the nerves supplying the skin. 
 This affection, designated as herpes zoster, is in associa- 
 tion with the outbreak of similar vesicles on the skin ad- 
 joining the lids, and often on the eyeball. A sharp line of 
 demarcation separates the inflamed area from the unin- 
 
 FiG. 62. — Congenital ptosis. 
 
 volved side of the face. In the event of ocular complica- 
 tions, serious impairment of vision may follow. 
 
 Diseases of the Orbit. — Injuries to the orbit may 
 cause fracture of its bony walls, and by implication of the 
 optic nerve as it passes through the bony aperture in the 
 apex of the orbit, may lead to sudden and complete blind- 
 ness. The orbit may be the seat of tumors which cause 
 displacement of the globe and interfere with vision. 
 
 On account of the proximity of the large air spaces, or 
 sinuses, which communicate with the nose, the cavity of the 
 orbit not infrequent^ participates in inflammatory condi- 
 
DISEASES OF THE EYELIDS 159 
 
 tions of those structures. Pus in a sinus may give rise to 
 abscesses in the orbit, and the inflammatory process attack- 
 ing the eye may lead to serious disease of that organ. 
 
 Diseases of the Lachrymal Apparatus. — Diseases 
 of the lachrymal gland are rare. Derangements of the ex- 
 cretory portion of the apparatus, however, of the canaliculi, 
 the small apertures situated upon the nasal extremities of 
 both lids, of the sac and of the duct, are very common. In 
 consequence of such disorders, the tears cannot pass from 
 the conjunctival sac into the nose, but flow instead over 
 the lid upon the cheek. This annoying condition may also 
 be occasioned by anything which interferes with the nice 
 coaptation of the lids to the globe, a requisite in the proper 
 conveyance of the tears into the sac. 
 
 Injuries of the lids and inflammatory changes in their 
 structures are examples of some of the conditions which 
 alter their position. Annoying lachrymation seems to ac- 
 company advancing years, especially in men, upon expos- 
 ure to wind and cold, due doubtless to an atony of the 
 muscle fibres which surround the sac and aid in the ex- 
 pulsion of its contents. The most common underlying con- 
 dition, however, is nasal disease, the inflammation mounting 
 from the mucous membrane lining the nasal cavity to that 
 of the duct. Repeated swelling leads to a gradual occlu- 
 sion of the duct and a damming back of the tears and 
 mucus in the sac. After a time, the sac becomes distended 
 and a perceptible tumor forms just below the inner angle 
 of the eye. If this be pressed by the finger, a quantity 
 of mucilaginous-like matter wells up into the eye, and in 
 cases of long standing, in which inflammatory changes 
 have arisen in the mucous membrane of the sac, a thick 
 creamy pus may often be expressed. 
 
160 HYGIENE OF THE EYE 
 
 At times the sac becomes the seat of an intense inflam- 
 matory reaction (Fig. 63), giving rise to great pain and 
 occasioning marked swelling and redness of the lids and the 
 adjacent skin. Unless there be surgical intervention, an 
 abscess forms, which usually ruptures through the skin 
 over the sac and occasions a permanent fistula. 
 
 Lachrymation is not always dependent upon improper 
 drainage, but may be of reflex origin, being an accompani- 
 ment of almost all diseases of the eye and frequently ex- 
 
 FiG. 63. — Abscess of lachrymal sac, and mucocele. 
 
 cited by eye-strain. The physician in his endeavor to 
 relieve excessive tearing always excludes such reflex causes, 
 before directing treatment to the various structures of the 
 lachrymal apparatus. 
 
 Diseases of the lachrymal apparatus may be congenital 
 and the persistence of a catarrhal condition of the conjunc- 
 tiva of one eye should awaken the suspicion of faulty 
 lachrymal drainage. 
 
 Formerly, the introduction of probes through the 
 canaliculus, into the nose, to overcome any stricture in the 
 
DISEASES OF THE EYELIDS 161 
 
 sac or duct was largely practised, but in recent years this 
 painful and often unsatisfactory process has been sup- 
 planted by syringing the inflamed lachrymal passages with 
 astringent washes, and when this fails to obtain permanent 
 drainage, by the insertion of a piece of lead wire from the 
 eye into the nose. Such " stjdes," as they are called, may 
 be worn for years, without occasioning disfigurement or 
 discomfort to the patient. 
 
 In purulent cases, the excision of the sac is desirable, 
 an operation of some difficulty, but without danger to the 
 eye or subsequent disfigurement, the resultant scarring 
 being usually imperceptible. 
 
 Diseases or the Cornea. — As has been stated in de- 
 scribing the anatomy of the cornea, this structure may be 
 regarded as the window or watch crystal of the eye, its 
 transparency permitting the ready passage of rays of light 
 into the interior of that organ. Should, for any reason, its 
 transparency be interfered with, the passage of the rays is 
 hindered and vision interfered with in proportion to the ex- 
 tent and position of the opacity. If the opacity is periph- 
 eral and the pupillary area of the cornea escape, vision may 
 be normal. The slightest haze, however, of the central 
 zone is always attended with more or less impairment of 
 sight. 
 
 As the clearness of the cornea would be impaired were 
 it provided with blood-vessels, none are present, the nour- 
 ishment of the membrane being derived from neighboring 
 structures. Owing to this fact the cornea frequently suf- 
 fers, in consequence of disease of adjacent organs, also from 
 any devitalizing process in the body which diminishes the 
 circulatory force and nourishing power. 
 
 The cornea, furthermore, occupies a very exposed posi- 
 11 
 
162 HYGIENE OF THE EYE 
 
 tion and is frequently injured by foreign bodies and other 
 forms of traumatism. 
 
 It may be judged from the foregoing that disease of 
 the cornea, or keratitis as it is designated, is common, and, 
 as a matter of fact, this tiny membrane may exhibit an 
 astounding number of pathological conditions, which tax 
 the experience of even the most trained observer to prop- 
 erly appreciate and catalogue. 
 
 Consideration need only be given here of several of the 
 more common affections, with which it seems desirable that 
 the laity should be familiar. 
 
 Phlyctenular Keratitis or Eczema of the Cornea. — This 
 disease occurs for the most part in scrofulous children, but 
 occasionally in debilitated adults. Children so aiFected 
 present other signs of scrofula, i.e., a discharging nose, 
 swollen lips, enlarged lymphatic glands and diseases of 
 bones and joints. An eczematous condition of the face 
 and scalp is also frequently present. Many subjects are 
 distinctly tuberculous. The disease often follows the erup- 
 tive fevers of children, and occurs usually in warm and 
 moist weather. 
 
 The characteristic lesion, the phlyctenule, a collection of 
 cells around a terminal nerve filament of the cornea, dis- 
 integrates and forms a small ulcer. Such ulcers may heal, 
 leaving but a slight scar, or, under less favorable condi- 
 tions, spread both laterally and more deeply into the sub- 
 stance of the cornea, destroying its transparency, and in 
 some cases lead to its perforation, with subsequent escape 
 of the lens and humors within the eye. The enlarged 
 white staring eyes, so frequently observed in those blind 
 from ophthalmia neonatorum and from other destructive 
 types of conjunctivitis, may also be a sequela of corneal 
 
DISEASES OF THE EYELIDS 
 
 163 
 
 ulceration with perforation, and demonstrate how destruc- 
 tive to sight and appearance the involvement of this mem- 
 brane in an ulcerative process may become. 
 
 In consequence of the irritation of the exposed ner\^e 
 fibrils, the eyes in phlyctenular disease are extremely sen- 
 sitive to light, thereby occasioning the greatest distress 
 (Fig. 64) . The oculist witnesses no more distressing pic- 
 ture than a child with phlyctenular disease, its head buried 
 in its mother's bosom to exclude the light, with tears stream- 
 
 FiG. 64. — Little girl leaning over chair, with head buried in cushion — suffering from corneal 
 
 ulcers. 
 
 ing from the eyes, and with the added discomfort of the 
 eczematous and scrofulous complication just referred to. 
 It is obvious that the first appearance of corneal haze 
 demands most careful and rigorous local treatment and 
 the best of hygienic and dietetic care to build up the health 
 of the child to nourish the impoverished cornea. It needs 
 but a few days of inactivity as regards treatment to hope- 
 lessly destroy or at least seriously impair vision in such 
 cases for life. The folly of resorting to such household 
 
164 HYGIENE OF THE EYE 
 
 remedies as bandaging the eyes with tea leaves, in piercing 
 the ears, as is the custom in some of the southern countries 
 of Europe, in the hope of drawing off the inflammation to 
 another organ, or in securing anything short of the best 
 ophthalmic advice possible, must be evident. In cities, hos- 
 pitals and dispensaries abound where the poor ma}^ receive 
 especial care and treatment, and in the country the aver- 
 age medical practitioner is usually able to cope with such 
 cases. The social service worker is of the greatest service 
 in aiding in the treatment of this class of cases, accompany- 
 ing the patients to their homes and demonstrating to the 
 household all that is comprised by the term general hygiene. 
 Owing to the protracted nature of many forms of ulcer of 
 the cornea, in cities, especially where it is difficult for the 
 medical advisers to maintain a proper oversight over am- 
 bulatory cases, the social worker not only sees that treat- 
 ment is carried out, but assures the reporting of the patient 
 for clinical oversight and direction at the desired intervals. 
 
 Interstitial Keratitis. — The preceding description 
 dealt with an ulcerative inflammation of the cornea which 
 afl*ected primarily the superficial layers. Interstitial 
 keratitis, on the other hand, affects the deeper layers, and 
 in most cases is unaccompanied by ulceration, the inflam- 
 mation being attended with deposits of lymph in the cornea, 
 which do not ordinarily destroy the corneal tissue. Though 
 at times the infiltration of lymph may convert the cornea 
 into a perfectly opaque membrane, this opacit}^ is capable 
 of absorption, and after a variable period the cornea may 
 clear and vision be restored to normal. 
 
 In neglected cases, however, the outcome of interstitial 
 keratitis is fully as serious as that of inflammation of the 
 more superficial layers of the cornea, the disease having a 
 
DISEASES OF THE EYELIDS 
 
 165 
 
 marked tendency to spread backward into the interior of 
 the eye and involve the iris, cihary body and choroid. In 
 consequence of these comphcations, certain irremedial con- 
 ditions arise, which cause bhndness. 
 
 The most common causes of this type of keratitis are 
 syphihs and tuberculosis. Although at times excited by 
 acquired sj^philis, congenital syphilis, that variety which 
 
 Fig. Go. — Hutchinson's teeth. 
 
 is communicated to the offspring by tainted parents, is 
 usually responsible, the disease appearing generalh^ at 
 adolescence, though cases have been observed as early as; 
 six years and as late as thirty years of age. In rare cases 
 the disease may originate while the child is still in em- 
 bryonic form and incurable blindness be present at birth. 
 
 Syphilitic subjects of interstitial keratitis usually ex- 
 hibit other signs of congenital syphilis, the nose being 
 
166 HYGIENE OF THE EYE 
 
 sunken, the skin pale, the knee-joints inflamed, and the 
 face scarred with deep hnes radiating from the angles of 
 the eyes, nose, and mouth. A peculiar notching or chisel- 
 shape of the upper permanent incisor teeth is particularly 
 characteristic (Fig. 65), Inquiry will frequently elicit 
 that several " still born " births have preceded the birth 
 of the patient, or that several babies born previously have 
 died in early infancy. The experienced diagnostician can 
 frequently establish a diagnosis in such cases from the his- 
 tory alone without even a glance at the eyes. 
 
 Both eyes are usually affected. The first manifesta- 
 tions are a diffuse zone of redness about the cornea, a lack 
 of lustre in this membrane, some dread of light, and ex- 
 cessive lachrymation. After a time, small islets of opacity 
 form in the deeper layers of the cornea. These soon coal- 
 esce, increasing the haze of the membrane and preventing 
 access of the rays of light into the interior of the eyes. In 
 an effort to clear the cornea, blood-vessels from the sur- 
 rounding structures form at the corneal margin. 
 
 The symptoms persist for weeks and months, but if 
 promptly and energetically treated, the eyes may recover, 
 with practically normal vision. 
 
 Even in the event of recovery, the long suffering en- 
 tailed by interstitial keratitis and the weakness of the eyes 
 which persists for years afterwards make it a most formid- 
 able disease, and offer strong argument against the mar- 
 riage of those tainted with syphilis. Modern science has 
 evolved tests by means of which the existence of syphilis 
 in individuals may be definitely proven. In view of the 
 tragedies which may follow, it does not seem too much to 
 insist upon the submission of suspected contracting parties 
 
DISEASES OF THE EYELIDS 167 
 
 to such tests before parental and legal acquiescence to mar- 
 riage is granted. 
 
 Diseases of the Iris. — Diseases of the iris are second 
 to no others in their importance, either in the frequency of 
 their occurrence or in respect to the irreparable damage 
 which may arise from neglect or maltreatment of them. 
 In addition to inflammatory affections, the iris may be the 
 seat of congenital malformations, the most important of 
 these being so-called colobomata. These are gaps of vari- 
 able size, which may extend from the pupillary margin to 
 the periphery and in some cases may be continuous with 
 similar fissures in the ciliary body or choroid. In several 
 interesting cases of this nature reported by the author, the 
 pupil, in consequence of anomalous formations in the iris, 
 was elongated and slit-like, resembling that of the cat. 
 Such anomalies are often hereditary and may be observed 
 in successive generations. 
 
 The danger of iritis to the integrity of the eye lies in the 
 tendency the membrane has to adhere to the sublying lens, 
 in consequence of a tenacious exudate which is poured out 
 from the iris in an inflamed state. Such adhesions not 
 only influence the development of cataract by interfering 
 with the nutrition of the lens fibres, but also block the chief 
 avenue of escape of the intra-ocular fluid, as it flows from 
 the posterior to the anterior part of the eye, thereby 
 damming up the fluids within the eye and giving rise to 
 glaucoma. At times the exudate blocks the pupil and 
 hinders the passage of the rays of light into the eye. 
 
 Iritis is generally a disease of adult life and occurs much 
 more frequently in men than in women. In addition to the 
 visual disturbances with which it is attended, marked in- 
 flammatory symptoms are also present. The pupil becomes 
 
168 HYGIENE OF THE EYE 
 
 contracted and the blood-vessels suiu'ounding the cornea are 
 much congested, though those of the conjunctiva also take 
 part in the congestion. Pain is a constant symptom, usually 
 most aggravated as night approaches. There is no dis- 
 charge from the conjunctiva, though increased lachryma- 
 tion is easily excited by exposure to light or any other form 
 of irritation. The interstitial portion of the cornea usually 
 participates in the inflammation, and produces a diffuse 
 haze of that membrane. The ciliary body also rarely 
 escapes and the neighboring portions of the choroid show 
 implication. 
 
 The causes of iritis are varied. Some form of con- 
 stitutional disease or inflammatory focus elsewhere in the 
 body is generally responsible. 
 
 Acquired syphilis probably occasions more than half 
 of the cases. The so-called secondary stage of the disease 
 is particularly apt to be complicated by iritis, about the 
 same time as the characteristic rash breaks out upon the 
 skin; more rarely iritis appears in the tertiary period, in 
 which event solid rounded masses or nodules, the so-called 
 gumma of syphilis, appear either in single or multiple form 
 upon the iris. 
 
 Articular rheumatism is also accompanied by iritis, this 
 being especially the case when a gonorrhoeal element is 
 present. The causal connection between gonorrhoea and 
 iritis is often overlooked in consequence of the long lapse 
 of time which frequently occurs between the appearance 
 of the ocular manifestation and the primary attack of 
 gonorrhoea. The gonorrhoeal virus may, however, remain 
 dormant somewhere in the genito-urinary system for years, 
 and though incapable of exciting local irritation in the 
 genitalia may be absorbed by certain membranes of the 
 
DISEASES OF THE EYELIDS 169 
 
 body, such as the joints and iris. Iritis may, however, occur 
 in rheumatic subjects in whom no trace of gonorrhoea is 
 present, and some of the most intractable cases the author 
 has ever treated have occurred in old ladies suffering from 
 that disabling and deforming type of rheumatism known 
 as rheumatoid arthritis. 
 
 Tuberculosis may also play a causal role, and this is 
 particularly true in the negro, a race peculiarly suscepti- 
 ble to tubercular infection. Tubercular nodules of the 
 iris are readily distinguishable from the reddish-yellow 
 gumma of syphilis, by their characteristic grayish-white 
 appearance. 
 
 Formerly many cases of iritis were imputed to expos- 
 ure to cold and other extraneous causes. Recent investiga- 
 tion has shown that with the exception of those due to 
 accident, which will be described later, such agencies have 
 but little, if no, influence in precipitating an attack, while 
 inflammatory foci elsewhere in the body, such as decayed 
 teeth, diseased tonsils, inflammation of the surrounding 
 sinuses of the nose, etc., are responsible in many instances. 
 
 To the trained observer, the diagnosis of iritis usually 
 presents but few difficulties. Much mischief often arises, 
 however, in consequence of general practitioners and others 
 mistaking the condition for an attack of conjunctivitis, and 
 withholding the proper treatment so long that the adhesions 
 referred to above have had time to become fixed and un- 
 yielding. The prompt and complete dilatation of the 
 pupil with atropine or some other drug which acts similarly 
 is essential, in conjunction with the treatment of the sub- 
 lying constitutional or local source of infection or irritation. 
 
 The proper management of iritis should always be rele- 
 gated to an ophthalmologist, when this is possible, for there 
 
170 HYGIENE OF THE EYE 
 
 is some danger in those not thoroughly trained in the science 
 of ophthalmology supervising the instillation of atropine 
 into the eye. Inflammatory glaucoma often presents a 
 picture not very dissimilar from iritis, and cases have oc- 
 curred where the practitioner, judging the attack to be 
 iritis, and instilling atropine for its relief, has precipitated 
 blindness by employing a drug which dilated rather than 
 contracted the pupil. Fortunately, the severity of the 
 symptoms following usually leads to the recognition of the 
 error, and prompt operative interference saves the sight, 
 but the damage to vision likely to arise from such mistakes 
 is too great not to warrant every precaution being taken 
 to avoid them. 
 
 Diseases of the Vitreous. — Aff*ections of this humor 
 are always secondary to those of structures surrounding it, 
 and frequently give rise to impairment of vision, by the cre- 
 ation of opacities which vary greatly in size and number. 
 The most common symptom attending vitreous disease is the 
 appearance of motes or muscse before the eyes, which are 
 treated at length elsewhere (page 182) . Near-sightedness 
 of high degree is usually attended with considerable altera- 
 tion in the structure of the vitreous and becomes a factor 
 in the detachment of the retina which sometimes occurs 
 in this form of eyeball. Injuries of the eye which per- 
 forate into the vitreous not infrequently cause the loss 
 of the eye from suppuration, as its structure afl*ords a 
 fertile soil for the growth of virulent forms of micrococci. 
 
CHAPTER XI 
 
 DISEASES OF THE INTERIOR OF THE EYE; 
 CHOROIDITIS, RETINITIS, OPTIC NEU- 
 RITIS AND OPTIC ATROPHY 
 
 The diseases of the ocular structures which have just 
 been described are all more or less evident to external exam- 
 ination. It is true, as has been stated, that a diagnosis of 
 cataract or glaucoma cannot be substantiated without ex- 
 amining the interior of the eye, but even these two condi- 
 tions give some external evidence of their existence. Dis- 
 eases of the interior of the eye, however, demand an oph- 
 thalmoscopic examination for their detection, and the pos- 
 sibility afforded by this wonderful instrument of exploring 
 the fundus and studying the changes observed there, is one 
 of the greatest achievements of science. 
 
 Diseases of the Choroid 
 
 Like the iris, the choroid may also be the seat of con- 
 genital anomalies. The cleft or coloboma described in the 
 iris may be continued back into the choroid, or a similar 
 fissure may occur in the choroid alone without participation 
 of the former membrane. This anomaly is explained by 
 some obstacle to the proper closure of the cleft in the eye 
 which is present during intra-uterine life. 
 
 A more common condition is albinism, or congenital 
 lack of pigment in the choroid and iris. In consequence 
 of this absence of pigment, the iris presents a pinkish ap- 
 pearance, due to the reflection of light from the blood-vessels 
 within the interior of the eye. Albinism is associated with 
 
 171 
 
172 HYGIENE OF THE EYE 
 
 lack of pigment in the hair. Vision is usually much dis- 
 turbed, both on account of lack of protection from the ab- 
 sence of pigment, and by the presence of high refraction 
 errors. The condition is incurable. Several members of 
 a family are often affected and there is a marked heredi- 
 tary tendency towards the transmission of the condition. 
 
 As stated in a previous chapter, the choroid is the vas- 
 cular coat of the eye and in close association with the retina. 
 Inflammations of this membrane, which are invariably at- 
 tended with exudation, almost always cause involvement 
 of the latter, with resultant visual disturbances. Reduc- 
 tion in vision may also result from the haze of the lens 
 and vitreous which may be occasioned by choroiditis. 
 
 There are no symptoms of which the patient is con- 
 scious which may be said to be characteristic of choroiditis, 
 the diagnosis being made by means of the ophthalmoscope. 
 
 The changes observed in the interior of the eye in con- 
 sequence of choroiditis are, briefly, the presence of exuda- 
 tions, disturbance in the choroidal and retinal pigment with 
 absorption in the later stages, and vitreous haze, if this 
 humor be affected (see Plate II, D) . 
 
 Like diseases of other structures of the eye, choroiditis 
 assumes a multiplicity of forms, a description of which is 
 outside the scope of the present work. Disease of the 
 choroid accompanying myopia has already been referred to. 
 
 The chief causes of choroiditis are syphilis, tuberculosis, 
 other infectious processes in the economy, and an extension 
 of inflammatory processes from other ocular structures. 
 Tuberculosis may involve the choroid, either in the form 
 of single or multiple growths. When multiple, they are 
 usually associated with similar deposits in the membranes 
 of the brain and form part of the general symptomatology 
 
DISEASES OF THE INTERIOR OF THE EYE 173 
 
 of tubercular meningitis. Unfortunately, however, their 
 late appearance in the eye, usually but a few hours be- 
 fore death, detracts from their value in substantiating the 
 diagnosis of this, at times, obscure disease of the brain. 
 
 At times choroiditis may assume a suppurative char- 
 acter from infection from extraneous causes, or in rarer 
 cases by the transference of purulent emboli or clots from 
 some suppurating focus within the body. The former mode 
 of infection sometimes happens after injury of the eye, the 
 latter in puerperal fever following childbirth. Loss of 
 
 Fig. 66. — Sarcoma of the choroid. (After Leber.) The tumor, G, rises from the choroid 
 C, which everywhere lies in contact with the sclera. The retina, A'^, on the contrary, is detached 
 entirely from its bed under the form of a folded funnel. It retains its connection only ^ath the 
 papilla behind, and with the choroid along the ora serrata, O, in front. (Fuch's Ophthalmology.) 
 
 sight and subsequent shrinking of the eye always follow. 
 The choroid is the most frequent seat of malignant 
 tumors within the eye ( Fig. 66 ) . These may not only 
 destroy the eye, but may also cause death by metastasis or 
 spread to other organs. The most common form of 
 choroidal tumor is the so-called pigmented sarcoma, a 
 variety of cancer which affects the eyes of adults. The 
 growth of this tumor is ordinarily slow and vision may be 
 but little affected for a number of years. It is desirable, 
 however, that such tumors be detected as soon as possible 
 and the eye containing them removed, for early operation 
 
174 HYGIENE OF THE EYE 
 
 is the only means of preventing the spread of the cancer 
 and of saving the patient's life. In some cases, instead of 
 spreading to distant organs, the tumor breaks through the 
 eye and invades the orbit, necessitating the removal of the 
 eye with all the surrounding orbital structures. A local 
 recurrence of the growth in the orbit sometimes occurs 
 after the removal of the eye with the tumor enclosed and 
 without there being any evident invasion of the orbit. 
 
 Retinitis. — Diseases of the retina may assume a 
 variety of types, dependent upon their cause. All, how- 
 ever, have certain ophthalmoscopic manifestations in com- 
 mon, namely, haze and swelling of this membrane, exuda- 
 tions, and hemorrhages from the retina vessels, and more 
 or less implication of the optic nerve. The products of 
 inflammatory change within the retina may vary from an 
 almost imperceptibly small hemorrhage to a mass of blood 
 extravasation, and from a minute area of lymph efl^usion 
 to a saturation and infiltration of the retinal structure 
 which entirely changes its appearance. As retinitis is usu- 
 ally occasioned by some disease of the general system, such 
 as syphilis, tuberculosis or disease of the kidneys and blood- 
 making apparatus, the recognition of the various types of 
 inflammation is of great value to the clinician, and, as has 
 been said elsewhere, frequently leads to the early recogni- 
 tion of diseases whose existence has been unsuspected both 
 by clinician and patient. For a description of retinitis of 
 Bright's disease, and diabetes and of the blood-making ap- 
 paratus, see pp. 210 and 211. Of no less value are the 
 changes which occur in the retinal vessels, which have been 
 described in another chapter. 
 
 In consequence of advanced vascular disease, the main 
 artery of the retina may become obstructed by a clot and 
 
DISEASES OF THE INTERIOR OF THE EYE 175 
 
 sudden blindness ensue. Frequently such attacks of blind- 
 ness are but transient, vision being regained after a few 
 minutes. After a number of such attacks, blindness usu- 
 ally becomes permanent, indicating that the clot has filled 
 the lumen of the vessels and no more blood can enter the 
 eye. Sudden total blindness in one eye, without prelimi- 
 nary attacks of loss of sight, may at times be occasioned 
 by the lodgement of a clot or embolus, which has been 
 whisked off a diseased valve of the heart, into the central 
 artery of the retina. As a rule, but one eye is affected. 
 
 Mild forms of retinitis may be set up by uncorrected 
 errors of refraction and by exposure to intense light. 
 
 Retinitis may also occur in both congenital and acquired 
 syphilis, in the latter, as a rule, about a year after the in- 
 fection has been received. 
 
 Of particular interest to laymen, on account of its 
 sociological features, is a rather rare form of retinitis known 
 as pigmentary degeneration of the retina. This disease 
 of the retina is associated with a wasting or atrophy of 
 the optic nerve and is characterized by the deposit of 
 peculiarly shaped pigment masses in the substance of the 
 retina, and by hemeralopia or night blindness. This lat- 
 ter symptom, almost characteristic of the disease, evidences 
 itself in a marked reduction of the visual acuity as soon as 
 twilight appears, subjects of the affection who have had 
 but little difficulty finding their way about in daylight 
 being suddenly deprived of this power. In the terminal 
 stages of the disease, vision becomes much affected, and 
 useful vision is usually lost. This form of retinitis occurs 
 in deaf mutes and idiots, but in others also who have no 
 form of disease of the nervous system. The disease is 
 strongly hereditary and consanguinity of the parents of 
 
176 HYGIENE OF THE EYE 
 
 the patient has been discovered so often that there seems 
 to be no doubt as to the influence played by the intermar- 
 riage of relations. 
 
 In a statistical study made by the author some years 
 ago to determine the frequency of the relationship of con- 
 sanguinity to blindness in the United States, it was found 
 that the parents were related as cousins in 4.5 per cent, of 
 the cases recorded. Analysis of a large number of cases 
 of this form of retinitis has shown that consanguinity can 
 be traced in about 25 per cent, of the cases. These figures 
 seem sufficient proof of the liability of consanguineous mar- 
 riages to originate serious ocular disease and demonstrate 
 the desirability for the prohibition of such unions by law 
 and of their discouragement by society. 
 
 Retinal Detachment. — The retina under certain 
 conditions may become detached from the choroid and 
 encroach upon the vitreous, in consequence of effusion of 
 blood or lymph beneath its surface. 
 
 Upon ophthalmoscopic examination, the retina appears 
 as a floating grayish-white membrane with the retinal ves- 
 sels running over it. Naturally vision is much restricted, 
 the part of the visual field corresponding to the area of the 
 detachment being lost. This accident occurs chiefly after 
 blows upon the eye and head, near-sighted eyes being espe- 
 cially liable, in consequence of disease of the vitreous. 
 Certain diseases of the choroid and retina which are at- 
 tended with copious hemorrhage or lymph extravasations 
 may also give rise to the condition. The retina rarely 
 escapes detachment when tumors invade the interior of the 
 globe. 
 
 Treatment is usually unsatisfactory, though some cures 
 may be wrought if early treatment is inaugurated. Drain- 
 
DISEASES OF THE INTERIOR OF THE EYE 177 
 
 ing off the fluid from beneath the retina by means of an 
 incision into the sclera, and absorbing the fluid by sweat 
 baths and internal medication, while the patient lies flat 
 upon the back for a period long enough to insure the ad- 
 hesion of the retina to the sublying choroid, offer the best 
 chances for reestablishment of vision. 
 
 Tumors of the Retina. — The most common form of 
 tumor of the retina is a variety of cancer, glioma, so called, 
 which occurs not very rarely and for the most part in 
 young children. In the early stages there are no external 
 evidences of the disease, the existence of the growth being 
 usually first detected by the mother upon the appearance 
 of a whitish mass in the pupil. 
 
 If the eye with the contained tumor is at once removed, 
 there is some chance that the disease has been eradicated. 
 Unfortunately, however, such cases rarely come to opera- 
 tion until the optic nei^ve has been implicated, so that, after 
 varying intervals of time, there is either a recui'rence of 
 the growth in the orbit, or meningeal symptoms develop, 
 showing that the tmnor has invaded the brain. The sub- 
 sequent course is extremely distressing, the tumor mass 
 in the orbit attaining great size and occasioning marked 
 deformity. Death follows from the invasion of the brain 
 by the cancer. 
 
 Optic Neuritis. — As has been stated in a previous chap- 
 ter, the optic nerve is really a portion of the brain, con- 
 formed into a nerve-trunk to carry visual impulses from 
 the eye to the brain. ]Many diseased conditions within the 
 brain are manifest in the nerve, so that the opportunity 
 afforded by the ophthalmoscope of actually viewing and 
 studying the changes which occur in the head of this struc- 
 ture is made use of as a part of routine examinations in 
 
 12 
 
178 HYGIENE OF THE EYE 
 
 all cases of suspected disease of the central nervous system. 
 
 The optic nerve, being continuous through the medium 
 of its fibres with the retina, participates in many inflamma- 
 tions of that structure — indeed, it is usually more or less 
 involved in nearly all forms of severe inflammation within 
 the eye. The optic nerve may also be the seat of primary 
 inflammation, and shows a peculiar susceptibility to be 
 affected by a variety of diseases of the general system, 
 such as syphilis, diabetes, and renal disorders, and by the 
 action of certain poisons. It may also be the seat of 
 tumors. 
 
 Ordinarily optic neuritis manifests itself ophthalmo- 
 scopically by a blurring of the edges of the nerve, in con- 
 sequence of a swelling and opacification of the nerve fibres 
 as they pass over its edge to spread out over the surround- 
 ing retina, and the skilled observer has but little diffi- 
 culty in arriving at a diagnosis. At times, however, slight 
 degrees of blurring of the nerve edges and nerve fibre 
 opacification may be entirely physiological, and a nice judg- 
 ment and much experience is demanded to properly judge 
 of the true nature of the condition present. 
 
 The most striking changes in the nerve are observable 
 in cases of brain tumor (see Plate II, F) . Indeed the oph- 
 thalmologist is frequently the first to suspect the existence 
 of such a growth, the headaches occasioned by the tumor 
 being attributed by the patient to eye-strain, and ophthal- 
 mic aid sought in the expectation that glasses might relieve 
 this symptom. Ordinarily, despite the extreme swelling 
 of the head of the nerve which is discovered at the examina- 
 tion, vision is unaffected, the loss of sight which so con- 
 stantly attends cerebral growths manifesting itself later. 
 
 Frequently such tumors may implicate some of the 
 
DISEASES OF THE INTERIOR OF THE EYE 179 
 
 visual centres and tracts within the brain and one or more 
 of the nerves which supply the ocular muscles, so that the 
 results of the ocular examination are of the greatest im- 
 portance in the localization of brain growths, often en- 
 abling the neurologist and surgeon in attendance to deter- 
 mine with precision the exact site and something of the 
 nature of the intracranial growth. 
 
 As the cause of the optic neuritis in such cases has been 
 found to be dependent in large measure upon the increased 
 tension which such growths occasion within the brain, even 
 in cases where localizing symptoms are absent, or in which 
 the removal of the tumor from the brain is impracticable, 
 it has been found desirable to lessen the cerebral pressure 
 by trephining the skull, to avert the blindness which is 
 almost inevitable, in consequence of the damage wi^ought 
 upon the structure of the nerve. Such procedures are 
 known as decompression operations. 
 
CHAPTER XII 
 
 SOME VISUAL PERCEPTIONS 
 
 These may vary from the perception of " sparks " and 
 " motes " to the appearance of figm-es and objects and even 
 more comphcated hallucinations. While frequently but 
 the exponent of some diseased condition within the eye, 
 they are often occasioned by some disturbance transient or 
 otherwise of that portion of the brain which controls the 
 visual acts. Thus, for example, generally speaking, sparks 
 or phospheneSj as they are designated, are induced by 
 stimulation or irritation of the retina or of the optic nerve 
 and its proliferations into the brain; motes, or muscce^ as 
 they are called, are occasioned by the perception of imper- 
 fections within the eye. 
 
 Although the mechanism of the eye is extremely deli- 
 cate and accurate, its media are far from being uniformly 
 transparent, and it possesses many imperfections, which 
 prevent the functions of the component parts from always 
 being performed with absolute perfection. In addition 
 to a blind spot which is projected in the visual field, some- 
 what externally to the point of fixation at which the eye 
 may be directed, there are numerous imperfectly trans- 
 parent parts in all parts of the refracting media. The 
 rays of light in passing through these undergo local ab- 
 sorption and refraction and cast shadows upon the retina. 
 These motes may become evident when one looks directly 
 toward the sky or regards some resplendent and highly 
 illuminated object, as a field of snow, a sheet of white 
 paper^ or the field of a microscope. 
 
 180 
 
SOME VISUAL PERCEPTIONS 181 
 
 Were it not for the fact that the great majority of 
 people are unconscious of these imperfections which the eye 
 naturally exhibits as an optical instrument, its efficiency as 
 an organ of vision would be seriously interfered with. 
 Happily, however, they are totally ignored in the vast 
 number of instances, by the habitual inattention which is 
 paid to any indirect visual impression. 
 
 The attention of some, whose eyes are particularly 
 sensitive or have become greatly weakened by over-fatigue 
 and other causes, is at times engaged by these bodies, how- 
 ever, and their perception often excites the greatest anxiety 
 and discomfort. Such individuals become the ready prey 
 of charlatans, who add to their fears by the assurance that 
 such motes will lead to speedy blindness unless relieved 
 by their nostrums. These poor dupes are then subjected to 
 years of the severest treatment, only to have their muscse 
 still undiminished and their minds still burdened with 
 anxiety and fear of approaching blindness. 
 
 The presence of these natural or physiological motes 
 is a symptom of no great importance, for they are ob- 
 served in persons whose eyes are perfectly healthy, but 
 there are other muscce which are the eocpression of some 
 diseased state. This second variety is occasioned by an 
 opacity of some of the parts of the eye which are usually 
 transparent. The faintest haze of the cornea will throw 
 a shadow, and the slightest impediment to the passage of 
 the rays will distort the retinal pictures. A young lady 
 under the author's care with a diffuse haze of the cornea 
 sees twenty distinct moons whenever she regards that body. 
 In referring to the disturbance of objects occasioned by 
 the formation of a beginning cataract, an ancient authority 
 cites the case of the lamplighter of a castle, who was so 
 
18^ HYGIENE OF THE EYE 
 
 startled by the myriad of lights which burst upon his gaze 
 after he had lighted the lamps in the banquet hall before a 
 feast, that he feared a ghostly visitation. This disturb- 
 ance of images is one of the earliest signs of incipient 
 cataract, and often leads the patient to consult a physician 
 before any appreciable diminution in the vision has 
 occurred. 
 
 The most common form of motes is that caused by the 
 presence of floating bodies in the vitreous humor, the so- 
 called muscce volitantes. These assume various forms, 
 sometimes resembling spots of various shapes and sizes, 
 as that of a cobweb. More often there is the likeness of an 
 insect, as a spider, worm, or fly. Sometimes they look like 
 streaks or lines, and sometimes they resemble sparks and 
 stars, strings of bright beads, or filamentous bands. Al- 
 though usually kaleidoscopic, changing their form rapidly 
 and frequently, at times they remain stationary, and a 
 number of people have come under the author's notice who 
 have been conscious of muscae for twenty years or more, 
 without the slightest change in their number or form. 
 
 When they are numerous they interfere greatly with 
 vision and are a source of great annoyance. They move 
 with the eye and appear to descend when the eye is turned 
 upward and vice versa. These motes are most commonly 
 seen in myopic eyes, for in this form of eye, the retina 
 being situated more posteriorly, bodies floating in its vitre- 
 ous project large diffusion circles upon it; but they are 
 also observed in many diseases of the tissues of the eye, and 
 while they may often be of a harmless nature, they may 
 also be indicative of grave change within the eye, and their 
 presence should always be made the occasion for a careful 
 examination. 
 
SOME VISUAL PERCEPTIONS 183 
 
 As has been stated in the opening paragraph of this 
 chapter, visual perceptions of various kinds may be excited 
 by diseases of the brain. Nearly every form of insanity 
 is attended at some time or other by visions of hallucina- 
 tions, and these appear in an innumerable variety of forms. 
 Epileptic attacks are frequently ushered in by visual sen- 
 sations. These may be very slight at times, but a passing 
 obscuration, being compared by the patient to the appear- 
 ance of air that has been heated over a stove. The patient 
 
 Fig. 67. — Scintillating scotoma in migraine. (Posey & Wright; Courtesy Lea & Febiger.) 
 
 may be annoyed by the presence of a domestic animal, or 
 he may see troops of soldiers passing in review before him. 
 He may be startled by the appearance of a ghostly figure 
 or terrified by the apparition of a bloody spectre. 
 
 These subjective sensations may or may not be colored. 
 They are frequently described as resembling globes of fire 
 of different colors, which possess rotary movements of 
 greater rapidity at the periphery of the globe, but the most 
 common appearance is that which is known as the " forti- 
 fication spectrum " (Fig. 67). This is the appearance of 
 
184 HYGIENE OF THE EYE 
 
 rays of light resembling darts of fire which form a broken, 
 angular line, of which the edges rapidly vibrate as the spec- 
 trum passes across the field. At times, in place of the 
 spectrum, there may be sudden loss of sight. This is never 
 complete, for it involves but half the field of vision. The 
 visual defect may begin at the periphery or at fixation, more 
 usual in the former position. 
 
 The one-sided character of the perception is a common 
 characteristic of many visual sensations dependent upon 
 cerebral causes and is a common attendant of that form of 
 headache which is designated as sick headache ^ or migraine. 
 A young man under the care of the author, a clerk in a 
 sugar refinery, accustomed to add double columns of 
 figures, was always made aware of an attack of headache 
 of this nature by the disappearance of some of the figures 
 from the column. This case is somewhat similar to that of 
 a man who was only able to see the letters son upon a sign 
 which bore the name of Jacohson, 
 
CHAPTER XIII 
 
 CATARACT 
 
 By cataract is meant an opacity of the crystalline lens 
 or its capsule. 
 
 In ancient times it was supposed that the loss of sight 
 which could be relieved by the displacement of the lens 
 from behind the pupil was due to an opaque substance 
 which, cataract-like, had poured down over the anterior 
 surface of the lens. This erroneous view held until the 
 early part of the 18th century, when actual dissection dis- 
 covered that the obstruction offered to the passage of the 
 rays of light into the eye was dependent upon an opacifica- 
 tion of the lens itself. Cataract, therefore, is an opacity 
 within the eye, and not, as many laymen suppose, a skin 
 or membrane which forms upon the eyeball itself. There 
 is a popular impression that all opacities or growths which 
 appear on the eyeball are cataracts, forms of corneal 
 opacities and at times conjunctival growths, such as Pingue- 
 cula and pterygia, being mistaken for them. 
 
 Although in its later stages, the opacity of the lens 
 robs the pupil of its blackness and brilliancy and imparts to 
 it a greyish appearance, in its early development cataract 
 is imperceptible to the casual observer. 
 
 Cataracts may occur at any age, but are generally ob- 
 served in infancy or old age. Infants may be born blind 
 in consequence of them and extreme longevity is nearly 
 always associated with more or less haze of the lens. Cata- 
 racts are often hereditary and this is particularly true of 
 the congenital variety. The transmission, as a rule, is 
 
 18.5 
 
186 HYGIENE OF THE EYE 
 
 direct, the skipping of a generation being unusual. Cata- 
 racts of childhood rarely affect the entire lens and a degree 
 of vision is usually present. While generally amenable 
 to cure by operation, cataracts associated with various con- 
 genital ocular malformations are sometimes inoperable and 
 their possessors must be relegated to the ranks of the blind. 
 
 The most common form of cataract is that which occurs 
 in men and women alike in the later years of life and is 
 designated as senile cataract. In this class of cases, the 
 lens begins to lose its clearness usually after the 50th year, 
 small more or less isolated opaque areas appearing in vari- 
 ous portions of the lens. Fortunately, these opacities are 
 often in the periphery of the lens, and present no obstruc- 
 tion to the passage of the rays of light as they are re- 
 fracted by the central portion of the lens after leaving the 
 pupil. At times, however, the opacity of the lens occupies 
 the central zone from its very commencement and entails 
 serious impairment of vision when the cataract is still in a 
 very immature stage. 
 
 As opacities in the lens are rarely discoverable by simple 
 inspection, their presence is usually manifested by increas- 
 ing difficulty in seeing, and particularly in seeing near ob- 
 jects clearly. It is a matter of frequent observation that 
 patients may lose much of their keenness of perception for 
 distant objects without being cognizant of it, the loss in 
 vision being detected in an increasing disability in reading. 
 No reading glasses with which they are provided give a 
 satisfactory clearness and the persistence in close work oc- 
 casions headache, watery eyes and other forms of eye- 
 strain. At times symptoms directly referable to the visual 
 impairment occasioned by the irregular refraction of the 
 rays of light through the partially opaque lens will arise, 
 
CATARACT 187 
 
 and images are distorted and the perception of ob j ects will 
 sometimes be reduplicated. A candle-light, for example, 
 may appear double or triple. Exposure to sunlight will 
 dazzle an eye with central lenticular haze, such eyes seeing 
 best when the pupil is dilated in a diminished illumination. 
 
 The tendency of most cataracts is to become complete, 
 that is to say, the opacification gradually spreads through- 
 out the structure of the lens until its entire substance has 
 lost its transparency. This transition is rapid in some in- 
 stances, but in ordinary senile cataracts is extremely slow; 
 indeed, in many instances the opacification remains more 
 or less stationary after its initial development, and the 
 haze being localized in the periphery of the lens, many go 
 through life with such opacities, without any perceptible 
 limitations in vision and unaware of the existence of such 
 a condition. It is for this reason that ophthalmologists 
 are very chary of informing patients of the existence of 
 slight lenticular changes, every ophthalmologist of experi- 
 ence having had numerous examples in his practice where 
 an ill-advised information by others of the existence of 
 cataracts has caused much needless anxiety over a long 
 period of years. The author has in mind a lady approach- 
 ing 80 years of age, with almost normal vision in each eye, 
 who was told by a foreign oculist nearly 20 years ago that 
 she had cataracts. 
 
 Cataract to the lay mind means blindness, sooner 
 or later, and this diagnosis once rendered, it is impossible 
 to completely allay the suspicion of impending danger by 
 any qualifications as to slowness of development, etc. 
 While it is usually wise to inform some member of the 
 patient's family of the discovery of lenticular changes and 
 their possible import, to avoid future misunderstanding 
 
188 HYGIENE OF THE EYE 
 
 and possible recrimination, in most cases a patient should 
 only be told that he has cataract when appreciable diminu- 
 tion of vision is present or imminent. 
 
 While the lenses of most people in advanced life are 
 more or less hazy, senile cataracts are not a product of old 
 age alone, and other factors must be present to excite their 
 growth. The influence of heredity has been referred to; 
 various constitutional diseases also have their effect. 
 Among them, diabetes is especially liable to be compli- 
 cated by lenticular changes, and may cause cataracts at a 
 comparatively early age. Bright's disease and diseases 
 of the vascular system are also responsible in a num- 
 ber of instances, the lens suffering in its nutrition in 
 consequence of alterations wrought in the tissues of 
 the structures nourishing it, by an interference with their 
 circulation. 
 
 Workers over furnaces frequently develop cataracts, 
 through exposure of the eyes to the light and heat rays 
 emanating from the glowing coals. Flashes of electric 
 light of great brilliancy from short circuitings have also 
 produced total opacification of the lens. As will appear 
 later, cataracts frequently result from injury. Lenticular 
 opacity accompanies many diseases within the eye and the 
 loss of sight which attends many cases of disease of the 
 choroid and retina is dependent upon this cause. 
 
 The conviction is steadily growing among eye surgeons 
 that prolonged eye-strain is responsible for many cataracts, 
 and it is now generally recognized that the decrease in the 
 number of cataracts among city dwellers may be accounted 
 for by the improved conditions under which this part of 
 the community carries on its near work. As a rule, the 
 citizens of towns are provided with better means of illu- 
 
CATARACT 189 
 
 iiiination than their fellows in the country and are able to 
 avail themselves of the facilities offered by specialists and 
 special hospitals to obtain the proper glasses to correct 
 their refraction errors. Improper glasses can do much to 
 create changes within the eye which manifest themselves 
 as cataracts later. 
 
 The diagnosis of cataract is made by means of the oph- 
 thalmoscope. By means of this instrument and by focal 
 illumination, the character and nature of the lenticular 
 opacity may be carefully studied and noted, for cataracts 
 may assimie a gi'eat variety of forms, the recognition of 
 which is of great significance to the surgeon in determining 
 upon the course of treatment applicable to each case. 
 
 Generally speaking, the treatment of cataract is con- 
 sidered under two heads, that of incomplete or immature 
 cataract and that of complete or mature cataract. 
 
 When cataract is discovered in its incipient stages, after 
 the careful connection of the refraction by means of proper 
 glasses, the habits of the patient are inquired into and 
 changed if they are found to exert any possible deleterious 
 effect upon the eyes. The hours of close use of the eyes 
 are restricted and caution enjoined regarding their too- 
 prolonged use by artificial light. Frequent interruptions 
 of a half-hour to an hour in the near use of the eyes is 
 advised. 
 
 The care of the general health is essential and particu- 
 lar attention given to the condition of the skin, by daily 
 baths and regular exercise in the open air. The patient is 
 encouraged to take daily walks, their distance being de- 
 pendent upon age and strength. 
 
 Smoked glasses are often of service, to prevent daz- 
 zling by sunlight. Simple lotions are prescribed, to lessen 
 
190 HYGIENE OF THE EYE 
 
 any conjunctival irritation, also internal medication given 
 to reduce any congestion of the interior of the eye. 
 
 Notwithstanding the claims of certain classes of irregu- 
 lar practitioners who advertise their ability to cure and 
 absorb cataracts by certain nostrums and manipulations, 
 no form of treatment has yet been devised whereby this 
 may be accomplished, the improvement in vision thought 
 to be gained by such practices being either imaginary upon 
 the part of the patient, or due to an improved condition 
 of other parts of the eye, the opacification in the lens still 
 remaining the same. 
 
 While cataracts cannot be absorbed and hence cannot 
 be said to be cured by treatment other than operative, 
 their development may often be retarded, and every eye 
 surgeon of experience has many patients under his charge 
 who have attained a ripe old age without appreciable im- 
 pairment of vision. Frequent changing of glasses is often 
 necessary to conform with the alteration in refraction oc- 
 casioned by changes within the lens, and all patients with 
 cataracts should report for observation once or twice 
 yearly. ^ 
 
 In addition to the other forms of medication mentioned 
 above, the author is of the opinion that in some cases the 
 local use of dionine within the eye has some power to lessen 
 further lenticular opacification. 
 
 The cure of cataract consists in the removal of the lens 
 by operation. In young subjects while the lens is soft, this 
 is accomplished by introducing a special form of knife 
 needle into the eye, and by cutting the capsule of the lens, 
 permitting the aqueous humor to come in contact with the 
 lens substance (Fig. 68) . The effect of this commingling 
 of the two humors is finally to absorb the entire lens struc- 
 
CATARACT 191 
 
 ture, the capsule alone remaining. A second needling 
 operation, as it is called, divides this membrane, and the 
 passage of the rays of light is no longer impeded. Chil- 
 dren with congenital cataracts may be operated on by 
 this method \\athin a few months after birth, though it is 
 usually desirable to wait until 12 or 18 months of age 
 have been attained. 
 
 Cataracts in older subjects are not amenable to this 
 form of treatment, on account of the greater hardness of 
 the lens, and must be removed from the eye by an open- 
 
 FiG. 68. — Swollen opaque lens after needling. 
 
 ing made into the globe through the cornea and extracted 
 by the method indicated in the accompanying illustration 
 (Figs. 69 and 70). The first step in the operation con- 
 sists in the introduction of a wire frame or speculum to 
 separate the lids and expose the eye. The eyeball being 
 held firmly by a pair of forceps, the cataract knife is entered 
 at the junction of the cornea and sclera, somewhat above 
 the horizontal plane of the eye, and by gentle to and fro 
 movements is made to cut its way out at the upper ex- 
 tremity of the corneal scleral junction. The avenue of 
 
192 
 
 HYGIENE OF THE EYE 
 
 exit being now prepared, a small piece of the iris is ex- 
 cised to facilitate the expulsion of the lens and to prevent 
 
 Fig. 69, — Incision of the cornea for the removal of cataract. 
 
 Fig. 70. — Expulsion of lens through corneal incision. 
 
 prolapse of this membrane into the wound during the act 
 of healing. Following an incision into the anterior cap- 
 sule of the lens by a small but exceedingly sharp knife, the 
 
CATARACT 193 
 
 lens is cautious!}^ stroked out of the eye by a small spoon- 
 shaped instrument, and after a careful cleansing of the 
 wound to facilitate its proper closure and insure prompt 
 healing, the speculum is removed, the eyeball flushed out 
 with a mild antiseptic lotion and a bandage applied. 
 
 This extraction of the lens is usually performed under 
 cocaine ansesthesia, and is practically painless. The opera- 
 tion lasts but a few minutes, though the patient is incapaci- 
 tated for several weeks, until the healing process is finished. 
 In about half of the cases, a secondary operation is neces- 
 sary before satisfactory vision is obtained. This consists 
 in introducing a knife needle into the eye and clearing the 
 pupil of remnants of capsule and lens debris which some- 
 times remain after the primary operation. 
 
 If the eye from which the cataract has been removed 
 was practically of normal build, that is to say, emmetropic 
 before the cataract developed, after the removal of the 
 cataractous lens, it is necessary to supply the eye with a 
 focussing power equal in strength to the lens which has 
 been removed. This is accomplished by prescribing a lens 
 to be worn before the eye in spectacles of much the same 
 spherical strength as the crystalline lens. With this lens it 
 is usually necessary to combine a cylindrical lens of moder- 
 ate strength to correct the astigmatism resulting from the 
 corneal incision. 
 
 The cataract operation is successful in the majority of 
 cases, the patient being enabled to read the finest type with 
 the correcting lenses and to see sharply in the distance. 
 The wearing of such powerful lenses as is necessitated after 
 the removal of the lens is attended with some inconveni- 
 ence, the perception of objects lying outside of the focus 
 of the spectacle lens being naturally much less perfect than 
 
 13 
 
194 HYGIENE OF THE EYE 
 
 is the case in eyes from which the crystalhne lens has not 
 been removed. This visual limitation, however, is very 
 slight and should not detract from the proper apprecia- 
 tion and recognition of the great boon which this operation 
 has been to humanity. The restoration of a helpless blind 
 individual to activity, efficiency and happiness is an achieve- 
 ment for which humanity should be ever grateful to the 
 many surgeons of many diiFerent races, whose efforts ex- 
 tending over years of trial, led to the development and 
 perfection of the present form of procedure. 
 
 The operation is one of exceeding difficulty, and the 
 best results are naturally attained by the most able and 
 experienced. At times, however, even when performed 
 by skilful operators, with the most stringent attention to 
 antisepsis, and with the best of after care, inflammation 
 arises in the operated eye and vision is not restored. In 
 some instances this failure is due to technical difficulties 
 arising during the operation, but in the majority, to some 
 condition of health of the patient, which retards the heal- 
 ing process and favors the development of inflammation in 
 the eye. For this reason the operation is not always a 
 success in those who suffer from Bright's disease, diabetes, 
 tuberculosis, and certain forms of rheumatism, and in al- 
 coholics, though even in such cases perfect results are often 
 obtained, and the existence of such disorders are not deemed 
 a positive contradiction to it. 
 
 The careful operator will naturally avoid operating 
 until any ocular complication, such as disease of the tear 
 passages, which might possibly jeopardize the success of 
 the operation, has been removed. 
 
 In former years it was deemed unwise to remove a 
 cataract until it was ripe, that is to say, until the entire 
 
CATARACT 195 
 
 lens was entirely opaque and the eye quite blind. Later 
 experience and the perfection of methods have determined 
 this restriction to be unnecessary, and the rule adopted by 
 most operators where both lenses are cataractous and blind- 
 ness threatening, is to remove the cataract most advanced, 
 as soon as the vision in the best eye deteriorates to such a 
 degi'ee that reading is no longer possible or going about 
 unsafe, certain technical procedures recently perfected 
 rendering the removal of unripe cataracts practically as 
 safe as those which are fully matured. 
 
 From what has been said, it seems unnecessary to state 
 that a cataract once successfully removed cannot return, 
 it being impossible for the lens to regenerate itself. 
 
CHAPTER XIV 
 
 GLAUCOMA 
 
 The term glaucoma is used in a broad sense to cover 
 the whole series of morbid changes which are produced by 
 increased fulness or tension within the eye. Under normal 
 conditions, the pressure in the ocular chambers which pre- 
 serves the shape and tension of the eyeballs is constant, the 
 balance of secretion of the intra-ocular fluid and the amount 
 of blood and lymph within the eye being established by the 
 drainage and escape of these fluids through proper avenues 
 of exit. Should, for any reason, the balance be disturbed 
 and any hindrance offered to the escape of these fluids, 
 either by a stoppage in the drainage canals or by a change 
 in the constitution of the fluids, in consequence of which 
 their filtration powers through these canals is retarded, too 
 much fluid collects within the eye and the eyeball hardens. 
 As will appear presently, the consequence of this increase 
 in tension is most disastrous to sight, the tissues of the eye 
 being unable long to withstand the destructive effect of 
 the pressure exerted upon them. 
 
 Glaucoma exists under a variety of forms, which, how- 
 ever, do not differ in their essential nature, but only in the 
 degree and rate of increase of the tension. In what is desig- 
 nated as chronic glaucoma, the pressure increases very 
 slowly, without giving rise to any inflammatory symptoms ; 
 in subacute glaucoma the increase of tension comes on in 
 a succession of attacks, which are attended with marked 
 symptoms of congestion of the eyeball and more or less dis- 
 turbance of vision. In acute fulminating glaucoma, the 
 
 196 
 
GLAUCO]VL\ 197 
 
 rise in tension is rapid and maintained and is attended with 
 total blindness in the affected eye. 
 
 Glaucoma is further designated as primary or second- 
 ary. In the former, the disease arises independently of 
 any other affection within the eye, while in the latter it is 
 dependent upon or, rather, occurs as a sequel to some pre- 
 existing ocular disease. Secondary glaucoma needs no 
 further comment here, being of too technical a nature to 
 describe in a work of this kind. 
 
 Primary glaucoma is, however, of paramount impor- 
 tance to the layman, and the necessity of an appreciation 
 of its chief characteristics even more important perhaps 
 than that of cataract. Sight may be lost from cataract 
 and may be regained by operation, but the loss of vision 
 from glaucoma is usually incurable, and cannot be re- 
 gained. 
 
 While in the acute forms there are inflammatory symp- 
 toms which warn the patient of the existence of disease 
 within the eye, in the more common chronic form such 
 warning symptoms are absent, the patient imagining the 
 slight visual disturbance from w^hich he suffers demands 
 but stronger glasses for its correction. Should an optician 
 be consulted, instead of an oculist, as happens not infre- 
 quently, the disease if in its incipiency will be overlooked, 
 a pair of glasses prescribed, and perhaps even a second and 
 a third pair at later intervals, as the loss of sight pro- 
 gresses and the failure of the lens to give requisite vision 
 proves inadequate. If medical aid is then sought, the dis- 
 ease has often progressed so far that but little can be 
 done to check the disease and retain the vision that re- 
 mains, for the sight which has been once lost from chronic 
 glaucoma cannot be regained. 
 
198 HYGIENE OF THE EYE 
 
 The warfare waged in so many states by medical men 
 to restrain the activities of opticians and optometrists, has 
 been entirely with the view of protecting the public against 
 such disasters as arise from this prescribing of glasses b}^ 
 those untrained in all the branches of ophthalmic science. 
 The recognition of glaucoma in its early stages demands 
 a high degree of knowledge and training in this branch of 
 medicine, and unless the disease be recognized and treated 
 properly, more or less loss of sight is sure to follow. 
 
 If treated early, the cure of the condition may be at- 
 tained in many cases, and in others the sight saved for 
 many years. 
 
 Operative measures will save nearly all cases of the 
 inflammatory forms, provided they are instituted early in 
 the course of the disease. The danger in the inflammatory 
 varieties resides in the failure to obtain prompt operative 
 relief, either in consequence of delay in securing the ser- 
 vices of an ophthalmic surgeon, owing to remoteness from 
 medical centres, or to improper treatment administered by 
 some medical man, who has mistaken the glaucomatous 
 attack, on account of the attendant vomiting, for a bilious 
 seizure, or for an inflammatory condition of the conjunc- 
 tiva or iris. 
 
 As has been said, chi'onic glaucoma in its initial stages 
 presents nothing unusual to a casual inspection. The 
 ophthalmologist will detect, however, an unusual shallow- 
 ness of the anterior chamber and perhaps a slightly dilated 
 pupil. The ophthalmoscope will also reveal a commence- 
 ment of depression or cupping of the head of the optic nerve. 
 Physiologically, the hole in the sclera which permits the pas- 
 sage of the optic nerve into the ej^e is the weakest part of the 
 eye, and is therefore the first to give way when the intra- 
 
GLAUCOMA 199 
 
 ocular tension becomes increased. In consequence of the 
 pressure, the head of the optic nerve is pushed back, and a 
 cup-shaped depression formed, vision being seriously com- 
 promised by the damage inflicted upon the nerve fibres 
 as they leave the nerve to spread out over the retina. 
 
 While in the early stages, those who suffer from glau- 
 coma may not be aware of a visual disturbance other 
 than difficulty in reading, the ophthalmologist is frequently 
 able to map out blind spots and other losses in the visual 
 field. 
 
 The tonometer, an instrument devised to record the 
 hardness of the eye, also enables the ophthalmologist to 
 properly estimate the intra-ocular tension and gives posi- 
 tive proof of its elevation. 
 
 If untreated, the chronic glaucomatous eye slowly in- 
 creases in hardness until the rise in tension is even per- 
 ceptible to the examining finger. The pupil becomes more 
 widely dilated, and the cupping in the head of the nerve 
 deeper and deeper. After varying lengths of time, total 
 blindness ensues, and a greenish hue is imparted to the 
 pupil, whence the disease received its name. 
 
 The diagnosis of the inflammatory form of glaucoma 
 presents few difficulties, the sudden rise in tension being 
 attended with signs which are absolutely characteristic to 
 the skilled observer. A deep zone of congestion suiTounds 
 the cornea, the pupil is dilated, and unless the haze which 
 soon spreads over the cornea prevents, the cupping of the 
 nerve is demonstrable. In some cases, hemorrhages occur 
 in the retina. Vision is rapidly lowered, and if the af- 
 fected eye be directed toward a light, on account of the 
 haze of the cornea, circles of various colors are seen about it. 
 
 There is usually great pain in the eye, which often 
 
200 
 
 HYGIENE OF THE EYE 
 
 radiates into the temple and down the side of the nose, and 
 vomiting is provoked with other signs of severe physical 
 
 Fig. 71A. — Microphotograph of anterior part of a normal eye, showing the main channel 
 of escape for the intra-ocular fluid (a), i.e., tiie angle of the anterior chamber, open. (After 
 Collins in Posey and Wright; Lea & Febiger.) 
 
 Fig. 71B. — Microphotograph of anterior part of a glaucomatous eye, showing this angle (a) 
 closed. Iridectomy opens this angle by removal of part of the iris. (After Collins in Posey 
 and Wright; Lea & Febiger.) 
 
 depression. Sight may be entirely lost in a few hours, 
 never to be regained, unless operative measures are insti- 
 tuted. In the subacute variety, a remission in symptoms 
 
GLAUCOMA 201 
 
 usually follows after some hours, in which event the ten- 
 sion falls and the eye slowly regains its normal appear- 
 ance, vision mayhap being thoroughly restored. 
 
 While there is some difference of opinion regarding 
 the best means of conserving vision in chronic glaucoma, 
 it has long been established that some form of operative 
 procedure is demanded, and demanded with as little delay 
 as possible, in all forms of inflammatory glaucoma. 
 
 
 Fig. 72. — Incising the eye at the corneal margin for iridectomy. 
 
 The chief avenue of exit of the intra-ocular fluid is 
 through a porous space at the angle of the anterior cham- 
 ber, where the root of the iris and cornea join. By reason 
 of the rise in tension in glaucoma, this space is blocked, the 
 base of the iris becoming adherent to the neighboring 
 cornea. The aim of operators, therefore, is to open this 
 space, either by removing a section of the iris, or by cutting 
 
202 
 
 HYGIENE OF THE EYE 
 
 a hole into the eye in this position, to obtain a permanent 
 area of filtration. Various modifications of these two 
 methods of procedure, of iridectomizing (Figs. 71, 72, 73, 
 and 74) and trephining the eye, as they are called, are 
 in vogue, operators the world over being busily engaged 
 in perfecting methods which will best maintain a porous 
 space through which the fluids may escape from the eye. 
 Naturally, various medicinal measures, both general and 
 local, are also of value. 
 
 Fig. 73. — Iridectomy; a portion of the iris has been drawn through the cut in the sclera, 
 and excised close to its ciliary att^^chment by one or more snips of the scissors held parallel 
 to the scleral incision. 
 
 The results of these operations are often but short of 
 marvellous, eyes which have been blind for hours, indeed, 
 in some instances for several days, being restored to per- 
 fect visualizing organs. The world is indebted to von 
 Graefe, the famous German ophthalmologist, for this boon 
 to humanity, this distinguished surgeon being the first, in 
 1856, to restore vision in eyes blind from glaucoma by 
 iridectomy. Until von Graefe's discovery, blindness from 
 glaucoma was incurable. 
 
GLAUCOMA 203 
 
 While the results of operation are not so brilliant in 
 chronic glaucoma as in the inflammatory varieties, treat- 
 ment for this condition is far from hopeless, and vision may 
 be retained in many cases as long as life lasts, either by 
 some one of the forms of operation just mentioned, or by 
 the continuous use of myotics. Myotics are drugs, such as 
 eserine and pilocarpine, which have the property of con- 
 tracting the pupil and pulling the base of the iris away 
 from the cornea, thereby opening up the filtration angle 
 of the eye. The author has long been an advocate of the.ir 
 use and has reported cases where vision has been main- 
 
 FiG. 74. — Coloboma of iris after iridectomy. 
 
 tained for more than 20 years by their continuous em- 
 ployment. As their use necessitates an intelligence and 
 steadfastness which is not possessed by all classes of society, 
 and the more or less constant oversight of an ophthalmol- 
 ogist, this method of treatment is not usually resorted to 
 in all hospital cases. Operation is also reserved for cases 
 in which the use of myotics fails to control the disease. 
 
 Patients should be enjoined to follow the regimen as 
 to the curtailed use of the eyes, exercise in the open air, 
 etc., already described as applicable to cataract cases. Par- 
 ticular care should be given to the adjustment of the vascu- 
 
204 HYGIENE OF THE EYE 
 
 lar system and the lowering of a too high blood-pressure. 
 
 Glaucoma is a disease of middle life, true primary 
 glaucoma being but rarely met with earlier. Its cause has 
 never been accurately determined, though there is good 
 evidence that eyes with lenses relatively too large for the 
 circumlental structures about them are particularly pre- 
 disposed to the disease. Arterial sclerosis has been thought 
 to exert a causative influence, also gout. Uncorrected eye- 
 strain and the overuse of the eyes by faulty illuminants 
 are factors in some cases. An hereditary tendency can be 
 traced in a number of instances. The Hebrew race is espe- 
 cially liable to be affected. 
 
 In concluding this chapter, the author would make an 
 earnest plea for a wider dissemination of knowledge re- 
 garding the prevalence and dangers of glaucoma among 
 the laity. Treatment to be efficacious must be early ad- 
 ministered, and the likelihood of glaucoma being over- 
 looked in its initial stages, when in the event of failing 
 vision, opticians and optometrists are consulted instead of 
 qualified medical practitioners, must be recognized, and 
 the possibility of danger arising from such examinations 
 thoroughly appreciated. 
 
CHAPTER XV 
 
 THE PARTICIPATION OF THE EYE IN DISEASES 
 OF THE GENERAL SYSTEM 
 
 The eye is part, and a very important part, of the gen- 
 eral organism and participates in greater or lesser measure 
 with many, indeed if not all, of the various disorders and 
 diseases which affect the body. By reason of its par- 
 ticularly intimate association with the brain and nervous 
 system, there is scarcely any affection of these structures 
 without ocular implication, indeed the initial symptoms of 
 many of the most important of the morbid processes occur 
 in the eye, and it frequently is the lot of the ophthalmologist 
 to be the first to discover the existence of some serious 
 disease of the brain or spinal cord, which had hitherto been 
 unsuspected, both by the patient and his family physician. 
 A peculiarity^ in the behavior of the pupil excites the sus- 
 picion of locomotor ataxia, and the discovery by the ophthal- 
 mologist of a swelling of the optic nerve removes all doubt 
 as to the causation of the headaches from which relief may 
 be sought, and leads to the detection of a tumor of the brain. 
 
 The general practitioner judges of the state of the 
 blood-vessels and of the circulatory system of his patient by 
 noticing the condition of the blood-vessels, as it is mani- 
 fested in the color of the lips and nails, and in the general 
 appearance of the skin. The force and power of the cir- 
 culation is determined by the pulse, by an examination of 
 the heart, and by instrumental measurement of the blood- 
 pressure. The eye specialist, however, by means of the 
 ophthalmoscope, can look directly into the eye and actually 
 
 205 
 
206 HYGIENE OF THE EYE 
 
 observe the blood-vessels themselves. Since the discovery 
 of this instrument not only has much which was obscure 
 concerning local affections of the eye itself been explained, 
 but great aid has been afforded the general practitioner in 
 his diagnosis of diseases of the general system. The exist- 
 ence of so-called hardening of the blood-vessels, and un- 
 suspected diseases of the kidneys, liver and other organs 
 have frequently been brought to light by its use. The 
 obstetrician may be warned by the ophthalmologist of evi- 
 dences of the insidious poisoning of pregnancy before other 
 positive signs of this condition are manifest and may in- 
 augurate treatment which will save his patient from the 
 not infrequent fatal accidents of childbirth. 
 
 The more skilled and experienced the examiner, the 
 wider will be the revelations and interpretations of his 
 ophthalmoscopic examinations. How erroneous is it, there- 
 fore, for individuals to fail to avail themselves of all that 
 such examinations may reveal, when ocular aid is deter- 
 mined upon for the relief of troublesome symptoms. The 
 ability to use the ophthalmoscope understandingly and 
 to interpret its findings properly presupposes a thor- 
 ough medical training, and a knowledge of the various 
 pathological states of the body is only to be acquired by 
 years of study of diseases of the general system as well as 
 those of the eye. The ophthalmoscopic examinations by 
 others than physicians, therefore, examinations by optome- 
 trists, so called, and opticians, can only be superficial, and 
 the interpretations of their discoveries vicarious. 
 
 Anemia. — Diseases of the blood generally give rise 
 to changes in the blood-vessels of the retina, and in the 
 retina itself, which are readily observable by the ophthal- 
 moscope. In chlorosis, a form of ansemia observed in 
 
DISEASES OF THE GENERAL SYSTEM 207 
 
 young women with menstrual disorders, these changes may 
 be very pronounced and the involvement of the optic nerves 
 and attendant hemorrhages into the retina may seriously 
 compromise vision. The author has recorded several such 
 cases in which only the most rigorous treatment averted 
 blindness. 
 
 The insufficient nourishment afforded the ocular 
 muscles in anaemia is at times productive of symptoms of 
 fatigue following the close use of the eyes, and proper tonic 
 treatment must be added to the functional correction of 
 any existing refraction error before relief is obtained. In- 
 deed, in many instances the recognition and treatment of 
 anaemic conditions by hygienic and medical measures will 
 often remove the necessity of prescribing glasses. A cer- 
 tain dryness and congestion of the conjunctiva is observed 
 at times in angemic individuals, which resists local treat- 
 ment and only yields after the administration of iron and 
 similar tonics. 
 
 The retina participates in the severe implication of the 
 general system which accompanies that rather rare form 
 of disease, permcious ancemia; indeed, the occurrence of 
 retinal hemorrhages in a long-continued anaemia without 
 adequate cause often establishes the diagnosis between a 
 simple and pernicious type of the blood disease. In 
 leukcemia, another grave form of anaemia, the ophthalmo- 
 scopic changes are very striking and significant, and may 
 first call attention to the existence of the disease. 
 
 Simple loss or diminution in the quantity of the blood 
 is very rarely followed by ocular changes, the additional 
 predisposing factor of impoverished blood being seemingly 
 required to bring about changes within the eye. If the 
 loss of blood is dependent upon disease of some organ. 
 
208 HYGIENE OF THE EYE 
 
 such as the stomach or womb, serious disturbance of the 
 optic nerve and retina not infrequently follows, this being 
 especially the case when hemorrhages are repeated. 
 Hemorrhages from the lungs are much less apt to occa- 
 sion ocular changes than those from the organs just 
 mentioned. 
 
 Rhachitis — ^RiCKETS. — By reason of the impoverish- 
 ment of the general system, which is a constant concomi- 
 tant of this disease, ulcers of the cornea andr inflammatory 
 conditions of the conjimctiva occasionally arise. The most 
 important change wrought in the tissues of the eye is, 
 however, a peculiar form of opacity of the crystalline lens, 
 which may be either present at birth or arise shortly after- 
 wards. This particular form of opacity is limited and in- 
 volves the zone of the lens situated between its centre and 
 its circumference and is designated as " zonular " or 
 " lamellar " cataract. Vision is greatly interfered with 
 and the removal of the lens by operation is usually neces- 
 sary before sufficiently clear vision is obtained to enable 
 the individual to read small type. 
 
 Disease of the Blood-vessels. — In no other dis- 
 eased state of the body has the ophthalmoscope afforded 
 such aid in diagnosis as in the detection of changes in the 
 blood-vessels of the retina, and but few general practi- 
 tioners fail to avail themselves of the opportunity afforded 
 by the ophthalmoscope of actually observing the retinal 
 blood-vessels. It has been estimated by an eminent 
 authority that changes in the retinal vessels occur in nearly 
 half of all patients with general arterial sclerosis. 
 
 The importance of the early interpretation of these 
 vascular changes ma^^ be impressed more firmly, when it 
 is realized that they are part of the general vascular disease 
 
DISEASES OF THE GENERAL SYSTEM 209 
 
 which not infrequently eventuates in chronic kidney disease. 
 
 The pulsation in the retinal vessels can be plainly ob- 
 served by the ophthalmoscope, and certain affections of the 
 heart accompanied by marked changes in the pulse can be 
 readily diagnosed by a glance into the eye. 
 
 Cardiac disease may also manifest itself within the eye 
 by the formation of a clot in its principal blood-vessel, with 
 resultant blindness, which is usually fortunately limited to 
 one eye. The occurrence of repeated small hemorrhages 
 in the conjunctiva and retina in individuals on the far side 
 of 65 years is a bad sign for longevity, such occurrences 
 being frequently the precursors of cerebral apoplexy. 
 
 Diseases of the KmxEYS (Bright^s Disease) . — The 
 ocular changes excited by kidney disease are of paramount 
 importance and, occurring at times before other symp- 
 toms have made themselves manifest, in some cases even 
 before albumin has appeared in the urine, the oculist is 
 frequently the first to discover the existence of this dread 
 malady. By far the greatest number of cases exhibiting 
 retinal changes occur in chronic disease of the kidneys, but 
 the acute inflammations of these organs, which at times 
 accompany scarlet fever and pregnancy, and less frequently 
 those secondary to intermittent fever and chronic lead 
 poisoning, may also evoke them. Both eyes are usually 
 affected. It has been estimated that retinal changes dis- 
 coverable by ophthalmoscopic examination are found in 
 about 20 per cent, of all cases of chronic disease of the 
 kidneys. The average age at which the retinitis occurs 
 is over 40 years, varying, however, between 5 and 78 years. 
 The far greatest number, however, occur between 40 and 50 
 years of age. 
 
 The retinitis of kidney disease is more or less diag- 
 
 14 
 
210 HYGIENE OF THE EYE 
 
 nostic (Plate II, C) , that is to say, the hemorrhages and ex- 
 travasations which are found there as part of this general 
 disease assume more or less definite forms, so that the 
 skilled observer is, as a rule, able to determine the exist- 
 ence of the kidney lesion by even a cursory glance into 
 the eye. 
 
 Ophthalmoscopic changes accompanying disease of the 
 kidneys have a serious import, as they usually indicate a 
 marked progression of the disease, and indicate that unless 
 the greatest care is exercised, but a few years of life remain. 
 A carefully regulated manner of living, with the best of 
 medical care, may, however, prolong life for many years. 
 The author has in mind the case of a man of advanced 
 years who is still in fair health, in whom albuminuria, 
 retinal changes and other evidences of renal disease have 
 been present for at least eighteen years. 
 
 The extent to which vision is affected depends naturally 
 upon the extent and location of the changes within the eye. 
 Total blindness is rare, though vision is usually so seri- 
 ously compromised that the ability to read fine type is lost. 
 
 The loss of vision due to structural change within the 
 eyes must not, however, be confounded with the transient 
 attacks of total blindness which occur in kidney disease and 
 which are of urgemic origin, being dependent not upon 
 changes within the eye, but due to an irritation of the 
 brain centres governing vision by poisonous substances cir- 
 culating in the blood, the product of the kidney disease. 
 
 Transient puffiness of the lids, due to an infiltration of 
 the tissues of the lids, may occur in the early stages of 
 nephritis. Permanent oedema or thickness is a later mani- 
 festation of the disease. 
 
 Diabetes. — In this disease, which is characterized by 
 
DISEASES OF THE GENERAL SYSTEM 211 
 
 the occurrence of many obscure symptoms in the nervous 
 system and elsewhere in the organism and by the more or 
 less constant presence of sugar in the urine, the involvement 
 of the eyes is of frequent happening. The ocular mani- 
 festations are also varied, for nearly all the tissues of the 
 eye may be affected. The most important, however, are 
 the changes which occur in the ciliary muscle, in the lens 
 and in the retina, for it happens not infrequently that the 
 ophthalmologist is the first to call attention to the existence 
 of diabetes, by the discovery of the more or less character- 
 istic disturbances which the abnormal quantity of sugar in 
 the economy occasions in those structures. 
 
 It has been asserted that eye changes manifest them- 
 selves at some period during the progress of a case of 
 diabetes in at least two-thirds of all cases. Such manifesta- 
 tions may occur as early as nine years, though the greatest 
 proportion are observed between 60 and 70 years of age. 
 
 The changes occasioned by diabetes in the ciliary muscle 
 manifest themselves in disorders of the accommodation, 
 interfering very markedly with reading and all close use of 
 the eyes. Xot infrequently, individuals unaware of their 
 having diabetes, consult the ophthalmologist for stronger 
 glasses, on account of a paralysis, more or less constant, 
 in the muscles of accommodation. 
 
 Even more significant is the opacification of the crys- 
 talline lens which occurs in diabetes, with a frequency vari- 
 ously estimated from 4 to 25 per cent. Unlike haze of the 
 lens or cataract from other causes, apart from the con- 
 genital varieties and those which arise from injuries, dia- 
 betic cataract may occur at any age, being often seen in 
 subjects as young as ten years. Another point of dis- 
 similaritv between this varietv of cataract and all other 
 
212 HYGIENE OF THE EYE 
 
 forms of haze of the lens, is its spontaneous disappearance 
 at times, and the influence of proper treatment in lessening- 
 its density. 
 
 So frequent is the association between diabetes and 
 cataract, that it is a rule of eye surgeons to test the urine 
 of all cases presenting lenticular opacities for sugar. Its 
 discovery, while not contra-indicating the removal of the 
 cataract, for in many instances this may be accomplished 
 without accident, always arouses anxiety in the operator, 
 for at times complications occur which seriously mar the 
 success of the operation. 
 
 The retinal manifestations consist in hemorrhages and 
 extravasations which may seriously affect vision. Often 
 however, these yield to treatment and perfect sight is 
 regained. 
 
 Infectious Diseases. — Although nearly all fevers re- 
 sulting from infectious processes may exhibit ocular symp- 
 toms at some time or other in their course, it is beyond the 
 scope of this volume to detail all such complications. It 
 will suffice to refer briefly to the disorders the eyes are 
 prone to suffer in several of the more common of these 
 conditions. 
 
 As is well known, the eye symptoms of measles are 
 veiy marked. In the early stages the dread of light 
 and increased lachrymation often arouse the suspicion of 
 the true nature of the fever, and these symptoms, with 
 the attendant catarrhal inflammation of the conjunctiva 
 and the occurrence of ulcers on the cornea, often con- 
 tinue long after the fever has abated. Unless the eyes 
 receive suitable local treatment and the room is properly 
 darkened, the cornea may become the seat of ulcers, which 
 by occasioning later scar formation or even actual perfora- 
 
DISEASES OF THE GENERAL SYSTEM 213 
 
 tion of that membrane, may seriously jeopardize sight 
 throughout the rest of hfe. Thousands of children have 
 had their lives marred by neglect and injudicious treatment 
 during an attack of measles. All direct sunlight should be 
 shut out of the sick-room as long as fever is present, and 
 only as much reflected light permitted as may be tolerated 
 without pain. 
 
 In consequence of the weakness of the ocular structures, 
 all near use of the eyes should be prohibited during con- 
 valescence, being resumed only after the general system 
 has thoroughly recovered from the effects of the fever. 
 
 If corneal ulceration occur during the course of the 
 treatment, the practitioner in charge should seek the aid of 
 an ophthalmologist at once, and the advice of the specialist 
 should also be sought during convalescence, if any signs of 
 inflammation about the eyes persist during this period. 
 
 Too often the close use of the eyes is permitted earlier 
 than is proper, fostering the development of near-sighted- 
 ness and astigmatism. If errors of refraction are found to 
 be present after convalescence, it may be desirable to cor- 
 rect such errors by glasses, until the eyes have regained full 
 strength. 
 
 Scarlet Fever. — Like other febrile conditions, scarlet 
 fever may give rise to catarrhal conjunctivitis and marked 
 ulceration of the cornea. As a rule, however, the eyes 
 suffer but little in this disease, though inflammation of the 
 optic nerve and retina may be set up by complicating dis- 
 ease of the kidneys. Xot infrequently, eye-strain is com- 
 plained of during convalescence, and may persist after the 
 general health is reestablished. The importance of the 
 avoidance of too early use of the eyes and the correction of 
 all errors of refraction by suitable glasses is apparent. 
 
214 HYGIENE OF THE EYE 
 
 Diphtheria. — Apart from a destructive form of con- 
 junctivitis, which sometimes, though rarely, affects the hn- 
 ing membranes of the Hds, and certain forms of paralysis of 
 the eye muscles, which are also of infrequent occurrence, 
 the ocular lesion most frequently met with is the partial or 
 complete paralysis of one, or what is more usual, of both 
 ciliary muscles. This paralysis, which totally disables the 
 eyes for all close work, may follow even slight attacks of 
 diphtheria. The paralysis supervenes from 3 to 6 weeks 
 after the appearance of the disease, persists for weeks or 
 months and finally disappears, even in untreated cases. 
 Convex lenses, to supplement the inactive lens, by reason of 
 the paralysis of the muscle controlling it, are necessary for 
 all near work as long as the action of the ciliary muscle is 
 suspended. 
 
 Small-pooc. — Before the days of vaccination, it was 
 estimated that 35 per cent, of all cases of blindness were 
 due to this disease, whereas to-day the proportion ranges 
 from between 2 to 3 per cent. The eruption of small-pox 
 frequently occurs upon the lids, whence it spreads to the 
 cornea, causing ulceration and the production of dense 
 scars, or even perforation of that membrane. So virulent 
 is the poisoning of the system by this noxious disease that 
 almost all of the ocular structures may take part in the 
 general infection, and for the sake of conservation of vision, 
 if for no other reason, society should cooperate with the 
 State in the enforcement of vaccination laws and the com- 
 pulsory report and segregation of all cases. 
 
 Carelessness in vaccinating may result in the accidental 
 vaccination of the lids by fingers soiled with the virus, and 
 the loss of the eye may follow precisely as if the resultant 
 pustule had been part of the general infection. 
 
DISEASES OF THE GENERAL SYSTEM 215 
 
 At times, in children and the weak, a purulent, though 
 mild, inflammation of the cornea and conjunctiva may be 
 excited by an ordinary vaccination, which demands treat- 
 ment and exclusion of light for some weeks following the 
 inoculation. 
 
 Erysipelas. — This infection, usually involving the skin 
 of the head, may spread to the lids, causing abscesses and 
 subsequent deformities in these structures, and sometimes 
 ulceration of the cornea. The orbital tissues may also be 
 invaded, giving rise to inflammation of the optic nerve, with 
 resultant blindness or serious impairment of vision. At 
 times the inflammation spreads from the orbit to the brain, 
 and death ensues from meningitis or clot formation. 
 
 Typhoid Fever. — Fortunately, serious ocular lesions, 
 though sometimes observed in the later stages of the dis- 
 ease, are rare in this not uncommon fever. Corneal ulcers 
 and attacks of conjunctivitis common in all febrile diseases 
 are, however, occasionally observed. More important for 
 consideration in a work of this kind is the relaxation of all 
 the muscles of the eyes which accompanies the long con- 
 valescence, and the importance of the avoidance of all ocular 
 strain and the correction of all refraction errors until full 
 health has been regained. 
 
 Malaria. — jNIore or less typical ulcers of the cornea may 
 complicate malaria, but by far the most important lesions 
 affect the uveal tract, retina and optic nerve. 
 
 Influenza. — All of the ocular structures may be in- 
 volved by this bizarre disease, but none are sufficiently con- 
 stant to render them typical of it. Perhaps the most com- 
 mon are those resulting secondarily from diseases of the 
 adjacent air cavities which are connected with the nose. 
 The neuralgic pain and tenderness of the eye and the parts 
 
216 HYGIENE OF THE EYE 
 
 about the eye are usually dependent upon the involvement 
 of these structures and can be relieved only by appropriate 
 nasal and sinus treatment. 
 
 Whooping-cough. — Not infrequently, due to the con- 
 gestion of the ocular tissues by the spasmodic cough and 
 the violence of the effort, the sclera of both eyes may be- 
 come deeply suffused with blood, occasioning no little alarm 
 to the layman. The hemorrhage, however, is superficial, 
 just below the conjunctiva, and is quite harmless, being 
 totally absorbed in a few weeks. 
 
 Mumps. — Like all the infectious fevers, mumps may in 
 rare instances give rise to serious inflammation of the optic 
 nerve and retina. Ordinarily, however, the eyes are un- 
 affected. Rarely the lachrymal glands, by an extension of 
 the infective process to other glandular structures, such as 
 is observed more commonly in the testicles, may be affected 
 and pronounced swellings may appear under the outer por- 
 tion of each orbital ridge. 
 
 Cholera. — In consequence of the severe emaciation 
 wrought by this now fortunately rare disease, the eyes are 
 frequently seriously involved. The globes sink back into 
 the orbits, and the patient lying semiconscious, with lids 
 but partially closed, dust collects on the devitalized cornea 
 and extreme ulceration follows. 
 
 Leprosy. — Leprosy, also a rare disease in the United 
 States, has definite ocular symptoms, the leprous nodules 
 forming on the lids and at times on the eyeball. Deformi- 
 ties of the lids and dense opacities of the cornea are fre- 
 quent sequelse. 
 
 Tuberculosis. — It is not remarkable that this wide- 
 spread and common infective process should have frequent 
 ocular manifestations. The eyes of children are most liable. 
 
DISEASES OF THE GENERAL SYSTEM 217 
 
 but the lesions may appear at any age in individuals whose 
 resisting power to the specific organism carrying the dis- 
 ease is weak, as well as those unduly exposed to infection. 
 The most striking ocular lesions occur in the negro, a race 
 whose resisting power to the disease is extremely low. 
 Xearly all the parts of the eye may be affected, but the 
 cornea, iris, and choroid are chiefly liable. 
 
 In rare instances, the eye may be the primary seat of 
 tuberculosis. Usually, however, the ocular manifestations 
 are secondary to tuberculosis elsewhere in the system. 
 When seated in the iris, the tuberculous masses present a 
 very characteristic appearance, rising out of the dark tis- 
 sue of the membrane as small grayish- white cone-shaped 
 masses, resembling small sugar loaves. The discovery of 
 similar though smaller nodules in the choroid, by means of 
 the ophthalmoscope, may establish the diagnosis of tuber- 
 culosis in cases of obscure meningitis, though the value of 
 this discovery from a prognostic or therapeutic standpoint 
 is minimized by the fact of their occurrence so late in the 
 disease. 
 
 The most common seat of tuberculosis is in the cornea, 
 and especially in the cornea of children, giving rise to the 
 condition already described as phlyctenular or scrofulous 
 keratitis. As the treatment and sociological features of 
 the disease were fully dwelt upon at that place, a repetition 
 is unnecessary. It is only necessary to emphasize that, as 
 with tuberculosis elsewhere in the system, personal hygiene 
 and h^^gienic surroundings have much to do with the pre- 
 vention and cure of tuberculosis, and the ophthalmologist 
 who essays to cure local manifestations of tuberculosis must 
 avail himself not only of proper local medicament, but also 
 
218 HYGIENE OF THE EYE 
 
 of all that modern science has taught may be done to com- 
 bat and control this prevalent infection. 
 
 Yenereai. Diseases. — Gonorrhoea. — This disease, af- 
 fecting the genital apparatus of both male and female, is 
 of particular importance to the eye surgeon in as much as 
 fully 25 per cent, of the blind owe their affliction to it. 
 Affecting at some time or other in their^J^ives from 60 to 
 80 per cent, of young men and a considerable proportion 
 of women, gonorrhoea is a menace to society which demands 
 the most careful consideration for its control and elimina- 
 tion. How this may be accomplished is still a matter of 
 debate, but undoubtedly one of the most potent agents for 
 its combat is a dissemination among the laity of a knowl- 
 edge of its prevalence and dangers. No boy or girl should 
 be allowed to approach the age when they may be exposed 
 to its dangers without some knowledge of its existence and 
 should be admonished as to the necessity for purity if for 
 none other than sanitary reasons. As the effects of this 
 disease have been treated so thoroughly elsewhere, it will 
 only be necessary to repeat in this chapter that gonorrhoea 
 is the causal factor in most cases of inflamed eyes of infants 
 at birth (see p. 129). Adults lose their sight by carrying 
 the noxious organisms from the infected genital organ to the 
 eye by the fingers or through the medium of a soiled hand- 
 kerchief. Less serious ocular complications arise in conse- 
 quence of a systemic poisoning from gonorrhoea and an 
 implication of the tissues of the eye through the blood. 
 
 Of equal importance from a social as well as a medical 
 aspect is the effect of syphilis upon the eye. This loath- 
 some disease, affecting probably 10 per cent, of the in- 
 habitants of all the larger cities of the world, is an infectious 
 process, caused by a definite germ and readily transmissi- 
 
DISEASES OF THE GENERAL SYSTEM 219 
 
 ble in most of its forms to others. All the tissues of the 
 body may be affected by it, and its course, if treatment be 
 inefficacious, is terminated only with the life of the 
 individual. 
 
 Although syphilis is usually acquired in a much less in- 
 nocent manner than the following, the notes of a case cited 
 in a popular text-book on syphilis is descriptive of one of 
 the modes of contagion: 
 
 " A young and upright man kisses a girl at an evening 
 frolic. Shortly after he becomes engaged to marry another 
 girl. A supposed fever sore upon his lips causes him no 
 anxiety until a similar sore appears upon the ej^elid of his 
 betrothed and an eruption breaks out upon his own body. 
 Then to the family physician, who finds both syphilitic." 
 
 Acquired syphilis begins after a few weeks' incubation 
 with a sore or chancre, as it is called, at the point of in- 
 oculation. A few weeks later, the secondary lesions put in 
 an appearance. These take the form of an eruption upon 
 the skin or of acute inflammations of various organs. After 
 these initial manifestations have disappeared, tertiary 
 lesions develop, as a rule in the deeper structures of the 
 body, and while they are often malignant in nature and 
 make great inroads upon the tissues of the body, they are 
 not infectious like the two preceding stages. 
 
 In hereditary syphilis, the disease is transmitted by 
 either parent and attacks the progeny with varying degrees 
 of virulence, generally, however, producing characteristic 
 deformities of the teeth, of the skull and the remainder of 
 the skeleton. 
 
 As has been learned by a perusal of earlier chapters, all 
 parts of the eye are susceptible to the poison of syphilis 
 and no age is exempt from its ravages. S3^philis frequently 
 
220 HYGIENE OF THE EYE 
 
 attacks the nervous system, and by involving centres in 
 the brain which control visual perceptions and ocular move- 
 ments, as well as parts of the spinal cord and the nerves 
 supplying the ocular muscles themselves, is indirectly re- 
 sponsible for many complicated and serious affections of 
 the nervous and motor systems of the eyes. 
 
 The control of syphilis demands even a more rigorous 
 campaign of education and enforced sanitation than that of 
 gonorrhoea, and the suggestions given to parents and edu- 
 cators in the paragraphs dealing with gonorrhoea are em- 
 phasized as being of even greater importance in safeguard- 
 ing the young against the evils of this widespread disease. 
 
 Diseases of the Sexual Organs. — In addition to the 
 changes observed in gonorrhoea and sj^philis which result 
 usually primarily from diseases of the sexual organs, at- 
 tention may be called, in the first place, to the ocular diseases 
 which accompany the various forms of imbalance in the 
 vascular and nervous systems which are excited by abnor- 
 mal menstruation. Latent inflammatory conditions of all 
 kinds are frequently made manifest by the menstrual 
 period, particularly if this be at all deranged or irregular. 
 Styes, conjunctivitis, and keratitis often recur, and even 
 more serious inflammations of the deeper structures of the 
 eye may be brought into activity. At the time of the meno- 
 pause, hemorrhages into the retina are not uncommon, and 
 an irritability of the nervous system provoked which often 
 manifests itself in a train of asthenopic phenomena. Under 
 such conditions, it is often impossible to prescribe glasses 
 which will enable the eyes to be used with entire comfort. 
 The conjunctiva is also congested and irritable and the 
 eyes water and are sensitive to light. Glaucoma, or hard- 
 ening of the eyeball, may appear at this time. 
 
DISEASES OF THE GENERAL SYSTEM 221 
 
 In pregnancy, the eyes are not infrequently the seat of 
 pigmentation, and if there be any sublying weakness of the 
 system, such as anasmia or kidney disease, inflammatory 
 conditions within the eye may be awakened which seriously 
 complicate the normal course of labor. On account of the 
 excessive tissue changes which accompany pregnancy, the 
 kidneys, liver and other organs are at times unequal to the 
 task put upon them, and toxsemia or blood-poisoning re- 
 sults. This manifests itself in early pregnancy by per- 
 nicious vomiting, later in persistent headache, failing vision, 
 motes, stomach pain, and restlessness. Examination of 
 the urine for albumin being negative, the obstetrician is at 
 times thrown off his guard, and the symptoms are re- 
 garded as local and of no particular import, until convul- 
 sions occur. It is in cases such as these, that an ophthalmo- 
 scopic examination is of particular value, the discovery of 
 retinal hemorrhages and exudates rendering the diagnosis 
 of toxaemia positive, and indicating the necessity for its 
 proper treatment. 
 
 It is only recently that obstetricians have appreciated 
 that changes in the retina which have been occasioned by 
 kidney disease and are almost certainly diagnostic of kid- 
 ney disease, may precede the presence of albumen in the 
 urine, and that the ophthalmoscope may give evidence of 
 disease of organs other than the kidneys, which has been 
 excited by the toxaemia of pregnancy. While the kidney 
 condition which arises in pregnancy is an acute one, in 
 many instances it is engrafted upon a chronic condition, 
 which has existed prior to pregnancy. The ophthalmo- 
 scopic examination under these conditions reveals in most 
 instances disease of the retinal vessels and informs the ob- 
 stetrician of the true condition of affairs. The usual oph- 
 
222 HYGIENE OF THE EYE 
 
 thalmoscopic picture of the kidney disease of pregnancy is 
 that of other varieties of Bright' s disease, consisting of 
 well marked inflammation of the optic nerves and retina, 
 with extravasations and hemorrhages. This form of retin- 
 itis occurs most frequently with the first pregnancy, but may 
 complicate later pregnancies also. The diagnosis of toxsemia 
 once made, the question of saving the life of the mother 
 must now be considered, as ocular symptoms occurring in 
 the course of pregnancy only arise in the event of a pro- 
 found autointoxication and the alternative of inducing labor 
 artificially must be weighed, the ocular examination being 
 frequently made the crux on which the decision is rendered. 
 It is generally held that in all cases which exhibit ocular 
 symptoms in the first six months of pregnancy, labor should 
 be induced at once, while women in whom the symptoms 
 appear in the last seven weeks should be carefully watched, 
 unless the retinal lesions are very severe. For under these 
 latter conditions the social condition of the parents and 
 the desire of the mother to have a child must be taken into 
 account, especially as the artificial induction of labor under 
 such circumstances does not always improve vision, and as 
 the life tenure of such women, like that of other subjects 
 of B right's disease, is generally much curtailed. Twenty- 
 five per cent, of such women lose their sight entirely, 29 
 per cent, make a full recovery, and 47 per cent, but a par- 
 tial recovery of visual acuity. 
 
 In the general blood-poisoning which sometimes fol- 
 lows later, puerperal septicaemia, septic clots may be carried 
 from the womb into the eyes, causing purulent inflamma- 
 tion of all the coats of the eye, with subsequent loss of 
 sight. 
 
DISEASES OF THE GENERAL SYSTEM 223 
 
 Infection following abortion may also result in septic 
 processes in the various coats of the eye. 
 
 During convalescence from childbirth, the need of 
 glasses for the correction of even trifling errors of refrac- 
 tion is often manifested. It is well, however, that the 
 mother should refrain from all near use of the eyes until 
 she has thoroughly recovered from the exhaustion and 
 anaemia of labor. 
 
 Birth often entails injury to the eyes of the infant. 
 This, as might be expected, is particularly true when in- 
 strumental delivery has been necessary. Hemorrhage into 
 the orbit, tears of the lids and even of the cornea, injury to 
 eye muscles, are some of the accidents which are not in- 
 frequently observed. When labor is very prolonged, hemor- 
 rhage may occur into the retina. 
 
 The diseases of the conjunctiva which may originate 
 during the birth of the child are considered elsewhere. 
 
 Diseases of the Skin. — ^On account of the anatomi- 
 cal and embryological relationship which exists between 
 the skin and the mucous membrane of the eye and the super- 
 ficial layers of the cornea, disorders of the skin frequently 
 involve the eye. This is particularly true of eczema and 
 herpes, and of various growths of a cancerous nature. Of 
 the association of eczema with the eye, consideration has 
 already been given under phlyctenular keratitis. In herpes, 
 blisters may appear upon the cornea and conjunctiva, and 
 occasion painful and persistent ulcers. More or less im- 
 pairment of vision usually follows. The numerous glands 
 in the lids render these structures peculiarly prone to in- 
 flammation, and styes or inflammation of those glands and 
 their surrounding tissues frequently accompany acne in 
 
224 HYGIENE OF THE EYE 
 
 other portions of the face and body. At times true fur- 
 uncles or boils attack the lids, causing marked tumefaction 
 and redness. Rarely lice {phtliinasis) bury themselves in 
 the roots of the lashes and disappear only after they are 
 suffocated by applications of suitable salves. 
 
 Dental Affections. — Abscesses in the teeth may by 
 the spread of the inflammation, give rise to orbital abscesses 
 and also to infectious processes within the eyeball. Other 
 dental affections of a less serious nature, in consequence of 
 the association between the nerve supply of the teeth and 
 eyes, occasion various functional ocular disturbances, such 
 as anomalies in the action of the ciliary muscle and reflex 
 disturbances in the visual field, due to vascular changes in 
 the retina and optic nerves. 
 
 Diseases of the Respiratory Tract. — The mucous 
 membrane lining the nose is continuous, by way of the 
 lachrymal passages, with the lining of the lids, so that in 
 many inflammatory conditions within the nose, there is 
 more or less irritation of the conjunctiva. Furthermore, 
 the orbital cavities in which the eyes are encased, are sur- 
 rounded by large air spaces, the so-called " accessory 
 sinuses" of the nose; which communicate with the nose 
 and are lined by a continuation of its mucous membrane. 
 
 These sinuses or cavities frequently partake in inflam- 
 matory conditions, and by reason of their close anatomical 
 relationship with the eyes and the nerves and muscles of 
 the eyes, occasion various derangements and inflammations 
 of those parts. The most frequent, perhaps, is orbital ab- 
 scess. In this condition, the tissues of the orbit are in- 
 flamed, the eyeball is pushed forward, the lids and con- 
 junctiva swollen and vision may be lost in consequence 
 of involvement of the optic nerve. In other cases, where 
 
DISEASES OF THE GENERAL SYSTEM 225 
 
 there is only a stoppage in the avenue of escape of the fluids 
 from the sinus into the nose, the cavity may be slowly dis- 
 tended and the eyeball slowly pushed out of place, in con- 
 sequence of the encroachment of the walls of the sinus into 
 the orbit. In both of these conditions, unless relieved by 
 operation, not only may vision be lost, but life itself, by an 
 implication of the brain and its membranes. 
 
 The ophthalmoscope is frequently of service to the nasal 
 specialist in the recognition of some of the more obscure 
 forms of sinus disease, particularly those situated near the 
 apex of the orbit, and in relationship with the optic nerves. 
 For the ophthalmoscope may reveal a congestion, and a 
 study of the visual field restrictions of various kinds, which 
 are more or less diagnostic of affections of those sinuses. 
 Double vision may result from implication of the ocular 
 muscles, and in rare cases, inflammation of the iris and of 
 other ocular structures may be secondary to sinus disease. 
 
 Adexoids and tonsillar disease, by depressing the 
 vitality and exciting inflammation in the mucous membrane 
 of the nose and its sinuses, may also be the indirect source 
 of various forms of disease of the conjunctiva and cornea. 
 The author has seen marked protrusion of both eyes caused 
 by an adenoid in the pharynx of a young child, which dis- 
 appeared after the removal of the growth. In like man- 
 ner, tonsillar disease may be the means of introducing 
 poisonous material into the system which may act deleteri- 
 ously upon the tissues of the eye. The most common 
 poison introduced in this way is that of rheumatism, and 
 there seems to be ample evidence that many inflammatory 
 conditions of the iris and of the uveal tract generally are 
 dependent primarily upon disease of the tonsils. 
 
 Diseases of the ear may interfere reflexly with the 
 
 15 
 
226 
 
 HYGIENE OF THE EYE 
 
 ocular movements, and excite to and fro movements of the 
 eyes, " nystagmus " so called (see p. 70). 
 
 Mastoid abscess has been followed by paralysis of eye 
 muscles and orbital abscesses. 
 
 Exophthalmic Goitre (Graves' or Basedow's Dis- 
 ease). — This affection, of unknown oVigin, though prob- 
 ably dependent upon some disturbance of the central 
 nervous system, is characterized in most cases by a group 
 
 Fig. 75. — A case of exophthalmic goitre. (From Wilbrand and Saenger.) 
 
 of symptoms which consist of increased frequency of the 
 pulse, enlargement of the thyroid gland, or goitre (Fig. 
 75 ) , the presence of certain characteristic ocular changes, 
 a fine nervous tremor and nervous irritability. 
 
 The most striking ocular symptom is the exophthalmus 
 or prominence of the eyes, which is present in greater or 
 less degree in almost all cases. This protrusion of the 
 eyes may be so great that complete closure of the lids is 
 
DISEASES OF THE GENERAL SYSTEM 227 
 
 impossible, and corneal ulceration results from exposure. 
 Usually both eyes are involved; the protrusion may, how- 
 ever, be limited to one. Almost equally constant Avith the 
 exophthalmus are various anomalies which may be noted 
 in the action of the lids. The most striking of these is the 
 so-called " Graefe lid sign," which consists in ^n inability 
 of the lids to follow the eyes in all downward movements. 
 This and the "Dalrymple sign," the name given to an abnor- 
 mal widening of the lid fissure, give to the eyes a peculiar 
 staring expression, and prominence to the sclera or whites 
 of the eyes, and with the exophthalmus serve to attract the 
 attention of even casual observers to the existence of the 
 affection. Other lid symptoms and paralyses of eye muscles 
 may also occur. The slightest evidence of the disease de- 
 mands instant treatment, as rest and proper medication 
 may often avoid the operative measures which are necessary 
 in advanced cases. 
 
 Diseases of the Nervous System. — As has been stated 
 in a former chapter, the retina is really a peripheral por- 
 tion of the brain, the optic nerve serving to connect it with 
 the intracranial portion of that important structure. Fur- 
 thermore, of the 12 nerves emanating from the brain, which 
 control the various organs of the body, six have ocular 
 connections. There is scarcely an affection of the brain or 
 spinal cord, therefore, without ocular manifestations; in- 
 deed, often the earliest symptoms appear in the eyes, and 
 the oculist is the first to discover the rudiments of what may 
 become a systemic affection of the greatest magnitude. 
 
 On account of the close anatomic relationship between 
 the blood-vessels of the eye and those of the brain, it might 
 be supposed that congestion of the latter would be in- 
 variably followed by those of the eye. In consequence of 
 
228 HYGIENE OF THE EYE 
 
 certain local regulating conditions, however, the blood- 
 vessels of the eye frequently escape participation, and it is 
 only when the overfulness of the cerebral blood-vessels 
 has been of long standing that the ophthalmoscope reveals 
 changes in the retinal circulation. When there is an in- 
 crease in the intracranial pressure, hbwever, positive oph- 
 thalmic evidence is the rule. The most common cause of 
 such an increase is the presence of a tumor within the brain, 
 and, in such an event, swelling of the head of the optic 
 nerve is present in about 90 per cent, of the cases, indicat- 
 ing with certaint}^ the presence of such a growth, when all 
 other symptoms, save perhaps that of headache, are absent 
 (seep. 178). 
 
 Meningitis. — In the event of inflammation of the 
 membranes covering the brain, not only is the optic nerve 
 liable to be involved, but also the nerves supplying the 
 ocular muscles. This happens in consequence of the close 
 anatomical relationship of these structures with the 
 meninges at the base of the brain, and their involvement 
 by the exudate which is the product of inflammation in the 
 membrane. Some degree of optic neuritis is present in 
 some stage in almost all cases of meningitis, and although 
 unfortunately it does not evidence itself early in the dis- 
 ease, it is often of the utmost value in establishing the diag- 
 nosis, as the ophthalmologist has this means of difl*erentiat- 
 ing between typhoid fever or pneumonia, on the one hand, 
 and meningitis on the other. 
 
 The swelling of the nerve is rarely so great as that 
 occasioned by brain tumor, but the effect upon vision is 
 greater. Those who survive an attack of meningitis are 
 frequently handicapped thereafter by great reduction in 
 vision on account of unpreventable atrophy of the optic 
 
DISEASES OF THE GENERAL SYSTEM 229 
 
 nerves. 3Iinute multiple tubercular nodules in the choroid 
 are at times the means of diagnosing acute tubercular 
 meningitis. As they appear, as a rule, only but a short 
 time before death, their discovery is of but little practical 
 importance. 
 
 Hysteria. — Ocular symptoms frequently accompany 
 this disorder of the central nervous system, and manifest 
 themselves in a variety of ways. The mildest are those 
 already designated as asthenopia, or fatigue of the ocular 
 apparatus after the slightest near use. In severe cases, 
 partial or even total blindness may supervene, the loss in 
 vision being purely psychic and not dependent upon any 
 demonstrable structural change. Such manifestations not 
 rarely follow accidents of various kinds, and are often dif- 
 ficult to differentiate from the casual losses assumed by 
 malingerers for the purpose of recovering damage awards 
 after accidents. Usually, however, a careful study of the 
 fields of vision and an application of the tests known to 
 ophthalmologists for the detection of fraudulent symptoms 
 of blindness enable the diagnosis to be made. Drooping 
 and spasm of the lids are occasionally observed in hysteria 
 and at times the extra-ocular muscles show contractions. 
 
 Insanity. — The ordinary forms of gross mental aber- 
 ration are unattended with constant or dependent ocular 
 signs or lesions, and as in many such states there is no evi- 
 dence of anatomical change within the brain, the eyes also 
 show no deviations from the normal. Conversely, loss of 
 sight does not, as a rule, entail mental derangements. In 
 individuals, however, who are intellectually weak, it can be 
 readily understood how the loss of so important a sense as 
 sight might be of serious moment and even sufficient to 
 break the fragile chain of cerebration and cause insanity. 
 
230 HYGIENE OF THE EYE 
 
 The author has elsewhere recorded two such cases, in which 
 increasing bUndness from the development of cataracts 
 caused violent mental aberration. Operation upon the 
 cataracts and the restoration of vision was followed almost 
 immediately by a full and permanent\ return of the mental 
 processes. Similar cases have been reported by other 
 operators. 
 
 The delirium which manifests itself in about 10 per 
 cent, of all cases operated upon for cataract, some days 
 after the operation, is attributable to the constraint neces- 
 sary for a time after the operation, to certain nutritional 
 disturbances of the brain attending the enforced restric- 
 tions in diet, and to the intense preoccupation which seizes 
 some individuals prior to and after the operation. The 
 delirium is usually transient, and yields readily to proper 
 management. 
 
 General Paralysis of the Insane. — Some of the earliest 
 symptoms of this common form of insanity are ocular and 
 the clinician is often enabled by the pupillary changes pres- 
 ent to differentiate this serious condition from some tran- 
 sient mental aberration. It would be unwise, however, to 
 place too much dependence upon such pupillary changes 
 alone, and it is only in conjunction with other indications 
 that the clinician will attempt to interpret and draw his 
 inferences from them. Hallucinations (of sight, at times, 
 limited to one side of the field of vision) are common, and 
 may appear early in the disease. Paralysis of the various 
 eye muscles may also occur, and at times the optic nerves 
 show evidences of degeneration. 
 
 Deformities of the Skull. — The various forms of 
 cranial malformation, be they microcephalia, a too small 
 skull, or megalocephalia, a too large skull, are apt to be ac- 
 companied by some serious disturbance of the optic nerves, 
 
DISEASES OF THE GENERAL SYSTEM 231 
 
 either in consequence of pressure exerted upon the nerves 
 as they pass through the optic canals narrowed by the de- 
 fective development of the bones of the skull, or from some 
 involvement of the tissues of the nerve by the inflammatory 
 condition primarily concerned in preventing the cranial 
 growth. Hydrocephalus is frequently attended with vary- 
 ing degrees of visual disturbance dependent upon the 
 amount of pressure exerted upon the optic nerves. 
 
 AcKOMEGALY. — This disease, which is characterized by 
 an overgro^vth of the hands and feet, and striking change 
 in the facial expression, due to the overdevelopment of the 
 structures composing the features, possesses almost char- 
 acteristic visual symptoms. There are often marked promi- 
 nence of the eyeballs, occasional palsy of eye muscles and 
 frequent changes in the extent of the visual fields, the most 
 common of these being areas of dimness in the centre of 
 vision and loss in the outer halves of the visual fields. 
 
 Diseases of the Spixal Cord. — Pupillary, muscular, 
 and optic nerve changes are more or less common in many 
 forms of disease of the spinal cord, but in locomotor ataxia, 
 or tabes, the most common form of spinal disease, they 
 constitute a constant and most important part of the symp- 
 tom complex. The most significant of these are the pupil- 
 lary symptoms, as they appear early and often supply the 
 first positive indication of the nature of this serious dis- 
 ease. In addition to irregularities in their size, the pupils, 
 when exposed to the light, do not contract as is normally 
 the case, but remain unchanged, narrowing, however, as 
 the gaze is directed to some near object. Although pres- 
 ent in other morbid states of the nervous system, this pupil- 
 lary phenomena is an almost constant factor in locomotor 
 ataxia and enables the oculist, who is not infrequently the 
 first to detect it, in the routine examination of the eves for 
 
232 HYGIENE OF THE EYE 
 
 glasses, to direct the attention of the patient to the necessity 
 of a more extended examination of his nervous system. 
 
 Paralysis of one or more of the ocular muscles is also 
 common and a sudden attack of double vision may be the 
 means of directing medical attentioii to the existence of 
 tabes. Such double vision is frequently transitory, and, 
 disappearing in a few days, deceives the patient as to its 
 significance and gravity. In the latter stages, such palsies 
 are more apt to remain constant, and are frequently dis- 
 tressing and annoying to the individual. It is at this time 
 that visual disturbances from optic nerve disease appear, 
 and in a certain number of cases almost complete blindness 
 supervenes. 
 
 As locomotor ataxia in the vast majority of cases is of 
 sj^philitic origin, it is at times amenable to antisyphilitic 
 treatment. The importance of the early recognition of the 
 disease is apparent, therefore, and additional demonstra- 
 tion is given of the value of a careful systemic examination 
 of all the parts of the eye in all refraction work, and offers 
 an additional argument why such tests should not be re- 
 linquished to opticians and optometrists, who are unlearned 
 in medical science, and unable to detect or appreciate func- 
 tional deviations which may often be significant of serious 
 disease of the general system (Plate II, E). 
 
 Infantile Paralysis; Anterior Poliomyelitis. — 
 This disease of the spinal cord may also affect the brain 
 and sublying nervous structures and involve the eye 
 muscles. The author has reported several cases of this 
 nature, in which a permanent condition of strabismus, or 
 cross-eye, followed. He has also recently examined a child 
 who suffered total blindness from disease of the optic 
 nerves, consequent upon this mysterious scourge of 
 childhood. 
 
CHAPTER XVI 
 
 WOUNDS AND INJURIES 
 
 Notwithstanding the protection afforded the eye by 
 the orbit and the lids, its exposed position makes it pecu- 
 liarly liable to accident, while the delicacy of its structure 
 converts an injury which would be of trifling significance 
 elsewhere into a matter of extreme seriousness to the hap- 
 piness and earning power of the individual. The character 
 and nature of eye wounds and injuries are manifold, 
 ranging from the lodgement of a minute foreign body under 
 the lid to the complete disintegration of the globe by a 
 powder or dynamite explosion. 
 
 Many ocular injuries befall children and the eye sur- 
 geon is frequently called upon to do his utmost to save 
 eyes that have been injured by perforation by forks and 
 knives and scissors, by hat pins, by pens and pencils, and 
 all manner of household articles. The multiplicity of ob- 
 jects which can destroy sight by careless handling or im- 
 proper use is appalling, and no more valuable or humane 
 message can be given the layman than the plea for rigid 
 and unceasing care upon the part of parents, nurses and 
 all those having the care of children, that all pointed 
 articles be removed from the reach of these little ones. 
 
 When a foreign body lodges in the eye, such as a cinder 
 or dust granule, the natural tendency for the patient is to 
 rub the eye, not only on account of the fancied relief af- 
 forded by the friction, but also in the hope of dislodging 
 the offending body. This action, however, is only dele- 
 terious, serving to irritate the eye and imbed the foreign 
 
 233 
 
234 HYGIENE OF THE EYE 
 
 substance more deeply. The proper procedure to follow 
 in cases of this kind is to grasp the margin of the upper lid 
 with the thumb and finger of the hand and to draw it out- 
 ward and downward. By this simple maneuver the foreign 
 body will frequently become engaged in the lashes of the 
 lower lid and the eye freed of its irritant. If this device 
 fail, the aid of another person must be evoked. This person 
 should station the patient in front of a window, and care- 
 fully inspect the visible portions of the eye and conjunctiva. 
 Should the foreign body be seen, unless it is imbedded in 
 the cornea it may easily be removed by the dampened point 
 of a handkerchief. Should it. still remain hidden, the helper 
 should request the patient to look downwards, then, grasp- 
 ing the margin of the upper lid with the thumb and fore- 
 finger of the right hand, the lid should be pulled down- 
 wards, while, with the. left hand, the upper margin of the 
 cartilage of the lid, i.e.^ sl point about one-half inch above 
 the eye-lashes, should be gently depressed with the blunt end 
 of a pencil, while the margin of the lid is gently rolled back 
 with the thumb and finger already engaging it. By forc- 
 ing the patient to continue looking fixedly downward, a 
 full view is had of the conjunctiva lining the upper lid and 
 covering the globe, and a foreign substance may readily be 
 removed in the manner just described. The eye may then 
 be bathed in cold water containing boracic acid, if this pow- 
 der be at hand, and in a few minutes the eye will recover its 
 normal sensibility. 
 
 If the foreign body is situated on the cornea and can- 
 not be dislodged by gentle contact with the handkerchief, 
 medical aid should be sought. The damage inflicted by 
 well-intentioned but unskilled attempts at removal from 
 
WOUNDS AND INJURIES 235 
 
 the cornea of foreign bodies which have become firmly im- 
 bedded in the tough substance of that membrane is ex- 
 tremely grave and every eye surgeon of experience has been 
 compelled to remove eyes which have been lost by infection 
 consequent upon the removal of such bodies by dirty tooth- 
 picks, blades of knives, etc. Stringent measures should be 
 adopted in all industrial establishments forbidding, in ear- 
 nest terms, the attempts of fellow workmen and other so- 
 called " handy men " to remove such bodies from the eye. 
 Competent medical aid is alone capable of dealing with 
 such cases. 
 
 Nasal catarrh, in consequence of exposure to draughts 
 and the inhalation of dust and other irritating substances, is 
 common among workmen, and not infrequently disease of 
 the lachrymal passages takes part in this inflammation of 
 the mucous membrane of the nose. Once the protecting 
 covering of epithelial cells of the cornea is broken, micro- 
 organisms present in the diseased lachrymal sac gain en- 
 trance into the tissues of the cornea, and, in a few hours, a 
 purulent inflammation arises which usually leads to the 
 total loss of the eye. The careful surgeon will discover the 
 existence of such a complication and will take means to 
 combat it, before pronouncing even a simple wound of the 
 cornea to be free from danger. 
 
 After the removal of foreign bodies, the eye should be 
 carefully bandaged, to exclude irritants and to hasten the 
 reformation of the epithelial covering. If inspection shows 
 that the corneal tissue has been much damaged by the in- 
 jury, ice compresses and the instillation of atropine are 
 demanded. 
 
 A painful and often troublesome injury results from 
 
236 HYGIENE OF THE EYE 
 
 a scratch of the cornea by a finger-nail ( Fig. 76 ) , this acci- 
 dent happening not infrequent^ to mothers by an unex- 
 pected blow from a child's hand. Prolonged bandaging 
 and the best of medical care is usually necessary before the 
 healing of the torn cornea is attained. Women also suffer 
 injury to the conjunctiva and cornea from burns by curl- 
 ing irons. If at hand, a small quantity of white vaseline 
 should be placed inside the lower lid, the eye bandaged, and 
 medical assistance immediately obtained. 
 
 The cornea is also frequently injured by scratches h?/ 
 
 #' 
 
 ^^^ 
 
 fe- . .d 
 
 Fig. 76. — Erosion of cornea from finger-nail injury. 
 
 twigs and branches of trees, and the author has seen sev- 
 eral cases where severe injury was inflicted by the sharp 
 points of a chestnut burr. 
 
 The lodgement of caterpillar hairs within the eyelids 
 may give rise to a very severe inflammation of conjunctiva 
 and cornea, and may threaten the integrity of the globe. 
 
 Injuries are sometimes confined to the lids. The author 
 has, upon several occasions, seen the upper eyelid almost 
 torn away by hooks of various kinds. The skin of the lids 
 is frequently the seat of burns, and in the event of an ex- 
 plosion, if the spontaneous closure of the lids has not been 
 
WOUNDS AND INJURIES 237 
 
 quite quick enough to prevent, burning substances may 
 gain access to the conjunctival sac and may injure the eye 
 itself. 
 
 Perhaps the most common type of chemical hums is 
 that due to unslaked lime, the lime being splashed into the 
 face of mortar-mixers and plasterers. When this occurs, 
 the eye should be immediately flushed with an excess of 
 
 Fig. 77. — Adhesion of the lid to the globe after lime burn. 
 
 water and the patient hastened to an eye surgeon. At 
 times, burns are occasioned by acids, when a similar course 
 of treatment should be instituted. Ordinarily advice is 
 given to counteract burns from alkalies, such as lye, am- 
 monia, and lime, with weak acids like vinegar, and those 
 from acids with weak alkalies like dilute soapsuds. These 
 agents are not, however, always at hand, and water must be 
 relied upon to rid the eye of the offending substance. 
 
238 HYGIENE OF THE EYE 
 
 Burns are always of serious moment, often destroying 
 the eye, although the immediate consequence of the accident 
 seems trivial. Adhesions of the lid with the globe (Fig. 
 77) , corneal opacification and ulceration, and actual shrink- 
 ing of the globe itself are some of the sequelae which are 
 observed after this class of injury. 
 
 While surface wounds are often serious, injuries which 
 cause a perforation of the globe (Fig. 78) are invariably 
 so, not only on account of the damage done to structures 
 vitally concerned with the integrity of the eye as a visual 
 
 jif^' 
 
 Fig. 78. — Perforating wound of the cornea with prolapse of the iris. 
 
 organ, but also on account of the additional danger which 
 they occasion of the eye being lost from sepsis, in conse- 
 quence of the introduction of infective material. 
 
 The simplest form of perforating injury is one which 
 penetrates the cornea, but does not involve other ocular 
 structures. The prognosis for sight and uncomplicated 
 healing depends naturally upon the character and extent of 
 the injury. A clear-cut wound, inflicted, for example, by 
 a keen blade of a small knife, may heal rapidly, and inter- 
 fere but slightly with vision, though the usually attendant 
 
WOUNDS AND INJURIES 239 
 
 adhesion of the iris to the cornea, which occurs when the iris 
 is permitted to come into contact w4th that membrane, in 
 consequence of the escape of the aqueous humor, may neces- 
 sitate operative measures later. Jagged tears of the cornea 
 may, on the other hand, despite the healing process which 
 is often accomplished by the surgical covering of the wound 
 by transplanted flaps of conjunctival tissue, leave the eye 
 totally blind, though the sublying structures may have 
 escaped injury. 
 
 -J 
 
 Fig. 79. — The deadly scissors and the innocent victim. 
 
 When an eye is injured by hat pins, pen-knives, blades 
 of scissors ( Fig. 79 ) , and the dozen or more articles and 
 implements in common use, not only is the cornea per- 
 forated, but the lens and iris usually suffer as well. Even 
 without treatment, providing the object inflicting the in- 
 jury has been clean, in rare cases, the wound of entrance 
 may close after a time, and the eye recover with more or 
 less impaired vision. Usually, however, unless prompt 
 treatment is instituted, the eye is lost from infection or 
 subsequent shrinking. 
 
 At times the iris escapes in perforating injuries, and 
 the lens alone is involved. The capsule of the lens being 
 broken, the aqueous humor enters the lens substance and 
 
240 HYGIENE OF THE EYE 
 
 causes a general opacification of that structure, preventing 
 the entrance of rays of L'ght into the eye. After a time, 
 however, a diminution in the volume of the lens will be 
 noted, and a gradual disappearar^ce of the opaque lens 
 matter takes place by absorption. Necessarily, good vision 
 can then only be obtained by the superposition of a strong 
 convex spherical lens before the eye, to replace the crys- 
 talline lens which has been lost, a correction which is rarely 
 tolerated in comfortable binocular vision. 
 
 Wounds which penetrate into the vitreous and are of 
 large extent are usually attended with more or less loss of 
 that structure and collapse of the globe. Injuries which 
 involve the ciliary body are always regarded with grave 
 concern by the surgeon, as experience has shown that this 
 class of injuries is particularly liable to be followed by 
 sympathetic involvement of the fellow eye. 
 
 A person may suffer injury to an arm or leg and no 
 inflammation be excited in the fellow member, no matter 
 how severe the wound in the injured part, but if an eye is 
 injured or inflamed, especially if, as has just been cited, 
 the ciliary body is involved, there is always the possibility 
 of a sympathetic inflammation occurring in the fellow eye. 
 This peculiar characteristic has long been recognized, and 
 it is for this reason that surgeons urge early removal of 
 eyes which are at all likely to give rise to this trouble ; for 
 once the inflammation has been transferred, though but in 
 the slightest degree, no treatment or operation can stay its 
 progress, and the sympathizing as well as the injured eye 
 is usually lost. One of the saddest experiences of the eye 
 surgeon is an unsuccessful pleading with an ignorant or 
 stubborn patient to permit the removal of a worthless and 
 dangerous eye, a procedure which would remove all menace 
 
WOUNDS AND INJURIES 241 
 
 from its fellow, and to hear the demand for help which 
 comes later, after the good eye has become involved and 
 no surgical intervention or treatment is of avail. 
 
 It would seem almost at times that the decision of 
 whether an operation shall or shall not be performed should 
 not be left with the patients and their friends, who are, as 
 a rule, in no position to arrive at a sane judgment in the 
 matter, but should be referred to some kind of a medical 
 court. Apart from the needless suffering entailed by this 
 self-inflicted blindness, the subject is of importance from 
 an economic standpoint, as most of these individuals are 
 incapable of supporting themselves and become cares upon 
 the State. 
 
 Gun-shot Wounds of the Eye. — In the autumn, 
 during the open season for shooting game, gun-shot wounds 
 of the eye are not infrequent. These are usually occasioned 
 by small shot, and the wounds inflicted vary in proportion 
 to the number of shot entering the eye and the parts af- 
 fected. As a rule, wounds of this character are extremely 
 serious, and often cause the loss of the eye. Shot lodged 
 within the eyeball are readily located by the X-ray, but 
 being non-magnetizable, their removal is attended with 
 great difficulty and often leads to the loss of the eye. If 
 the globe has been perforated and the shot lodge without 
 the eye, useful vision may be saved provided no part of the 
 eye vital to sight has been injured. Wounds with balls of 
 large calibre are usually fatal to sight and generally de- 
 mand the immediate removal of the eye. A not infrequent 
 loss of sight from pistol wounds are those self-inflicted by 
 would-be suicides, who, holding the barrel of the pistol to 
 the temple in the expectation of blowing out their brains, 
 
 16 
 
242 HYGIENE OF THE EYE 
 
 advance the weapon too far forwards, and injure instead 
 one or both optic nerves just before they enter the eyes. 
 
 Another not uncommon source of injury is from a bullet 
 or stone hurled against the eye fro|m a sling-shot. In cases 
 such as these the globe is frequently not perforated, the 
 injury resulting from the blunt force with which the missile 
 strikes the eye. Rents in the iris and choroid, dislocation 
 of the lens, and detachment of the retina are the usual 
 sequelae. 
 
 It is beyond the scope of this work to describe the fre- 
 quent and extensive injuries inflicted upon the eyes in war. 
 They vary from the complete blowing out of the eyes to 
 every conceivable form of eye injury, the amount of dam- 
 age done depending upon the nature and form of the pro- 
 jectile and the part of the eye injured. 
 
 Injuries from Balls. — These may be inflicted by balls 
 of all kinds, i.e., cricket, base-ball, golf, tennis, racquet balls, 
 etc., and, generally speaking, the smaller the ball the greater 
 the danger to the eye. When a cricket or base-ball strikes 
 the eye, it often happens that the rim of the orbit, the bony 
 receptacle in which the eyeball lodges, receives the force 
 of the blow and the eyeball itself escapes. Unfortunately, 
 however, the consequences to vision may be very serious, for 
 it not infrequently happens that the force of the blow is 
 great enough to produce a fracture in one of the walls of 
 the orbit and the extension of the fracture to the apex of the 
 orbit causes a severance of the fibres of the optic nerve, as 
 that structure passes through the optic foramen, as it 
 emerges from the cranial cavity into the orbit. The prog- 
 nosis, therefore, in cases of sudden blindness following such 
 injuries, is hopeless. When, however, an interval of time 
 elapses before the loss in vision becomes manifest, there is 
 
WOUNDS AND INJURIES 243 
 
 some chance that sight may be regained, as in the latter case 
 the blindness may have been caused by a hemorrhage into 
 the sheath of the nerve, which is capable of subsequent 
 absorption. The author remembers a case of a young 
 father who, while romping with his little son, received a 
 violent blow over the eye from his child's head. There was 
 no loss of vision until some hours later and fully a day 
 elapsed before the eye on the injured side became totally 
 blind. After several days of blindness, full visual acuity 
 was gradually regained. 
 
 Fig. 80. — Rupture of the eyeball. 
 
 The circumference of the orbital aperture is too great, 
 however, to protect the eye from injury by small balls, and 
 most eyes struck squarely by racquet and golf balls are 
 hopelessly lost, the envelope of the eye being split (Fig. 
 80) and the contents of the eye extruded as a result of the 
 accident. If the blow has been a glancing one, the injury 
 may not be so serious, and the globe, partially flattened 
 for the moment by the blow, may escape without injury to 
 the cornea and sclera. Ordinarily, however, in such cases, 
 the iris or choroid is torn, the lens dislocated, and, what is 
 
244 HYGIENE OF THE EYE 
 
 usually of more serious moment, the retina detached 
 (Fig. 81). 
 
 In addition to participating in the class of injuries just 
 mentioned, golf halls may menaces^ the integrity of the eye 
 in quite another manner. During the past few years a 
 number of cases have been reported where severe burns 
 of the eye have been occasioned by boys and others, mostly 
 caddies and professional golfers, cutting into the balls to 
 ascertain their contents (Fig. 82) . Consequent thereto an 
 explosion of extreme violence occurs, the semifluid mass 
 
 Fig. 81. — Blood in anterior chamber following blow upon the eye. 
 
 contained in the core of the ball being expelled in all direc- 
 tions. Several eyes have been totally lost in this way and 
 others severely injured. Fortunately, this unhappy experi- 
 ence does not follow the incision of all golf balls, but ap- 
 pears to be limited to two kinds of balls, which were in 
 common use for a time on account of their lightness. It 
 would appear from an analysis which was made of the con- 
 tents of several of the balls after the explosions had oc- 
 curred, that the core consisted of a mixture of barium sul- 
 phate and a free alkali. In balls of another make, the core 
 
WOUNDS AND INJURIES 
 
 245 
 
 seemed to be made up of zinc chloride. Owing to the 
 initiative of the Pennsylvania Commission for the Conser- 
 vation of Vision, the United States Golf Association caused 
 placards to be displayed in all the club houses of the asso- 
 ciation, warning of the danger of cutting into golf balls. 
 The Massachusetts Legislature also passed a bill prohibit- 
 ing the sale of balls which contained any caustic fluid. 
 
 Fig. 82. — Cutting into a golf ball. The ball, at the centre, contains an acid which explodes 
 when exposed to the air. A great many cases of loss of sight have been reported as a result of 
 curiosity of the contents of golf balls. 
 
 While the two makes of dangerous balls have been 
 largely withdrawn from the market, it is not unlikely that 
 some of the balls may still be in circulation, so that the 
 caution recommended by the golf association should still 
 be given publicity, and caddies and others warned under no 
 circumstances to investigate the contents of golf balls of 
 any description. 
 
 Snoav Blfndness. — The dazzling reflection of the sun's 
 
246 HYGIENE OF THE EYE 
 
 rays from snow and ice fields is often a source of great 
 annoyance and danger to mountaineers and arctic ex- 
 plorers. Unless properly protected by some form of 
 colored or smoked glass, the excessive amount of ultra- 
 violet rays burns the conjunctiva or even the cornea, and 
 may cause serious inflammation. For protection against 
 snow blindness in arctic, antarctic, and mountaineering ex- 
 peditions, the best frame is the common open spectacle 
 frame, fitted with large mussel-shaped smoked or tinted 
 glasses. Glasses tinted yellow-gl-een entirely absorb the 
 ultra-violet rays and the colors of the landscape, seen 
 through them, are not much modified. All more or less her- 
 metical arrangements of goggles for the exclusion of side 
 lights have been found by travellers to be superfluous and 
 serve only to moisten the glasses. 
 
 Lightning stroke has been followed by cataract and 
 various other changes in the interior of the eye. The author 
 observed a case of diffuse oedema of the retina with total 
 loss of sight follow this accident. Full vision was ulti- 
 mately obtained in each eye. 
 
 Industrial Injuries to the Eyes^ 
 
 Statistics show that in the United States 75,000 per- 
 sons are killed annually through accidents. Of this num- 
 ber, 35,000 die from industrial injuries. Of 2,000,000 
 annual non-fatal accidents, probably 160,000 are accidents 
 to the eyes. 
 
 ^ Contents of this section based on a paper by the author 
 before the Department of Industrial Welfare and Efficiency, 
 Bureau of Commerce and Labor of the State of Pennsylvania, at 
 annual meeting, November 23, 1916, fromi material furnished by 
 the National Committee for the Prevention of Blindness. 
 
WOUNDS AND INJURIES 247 
 
 Although the last census records the number as smaller, 
 there is strong evidence to place the number of blind in our 
 country at about 100,000, of whom approximately 10,000 
 lost their sight as the result of accidental injury in in- 
 dustrial occupations. Quite apart from the suffering and 
 unhappiness entailed by these accidents, which cannot be 
 appraised in dollars and cents, it has been estimated that it 
 will cost the nation nearly ten million dollars to care for 
 these blinded workmen during the remainder of their lives. 
 
 According to a statement recently issued by the 
 National Association for the Prevention of Blindness, the 
 industries providing the greatest number of industrial ac- 
 cidents to eyes are foundries, galvanizing plants, machine 
 factories, metal and wood working plants, lead and color 
 factories, chemical works, and the dusty and poisonous 
 trades. The classes of workmen showing the largest per- 
 centage of eye accidents are smelters and furnacemen, 
 welders, grinders, and machinists, furnace helpers, and 
 railroad workers. It may appear rather strange that this 
 last class, railroad men, are so subject to eye accidents in 
 their work, yet the records of the great railway systems 
 which operate one-half of the total mileage in the United 
 States, admit for the period 1908-1910 seven cases of total 
 disability, i.e., loss of both eyes, while three hundred and 
 ninety suffered the loss of one eye. Railroad employees ex- 
 posed to eye injuries preventable by goggles are chippers, 
 riveters, boilermakers and grinders. 
 
 One of the greatest menaces to the eye is burns from 
 molten metal. This may occur in filling the ladle with the 
 metal while it is still in a liquid state, or when the latter is 
 being poured into the mould, the sparks flying in all direc- 
 tions, frequently burning the face and eyes of the work- 
 
248 HYGIENE OF THE EYE 
 
 men. Most serious are the explosions which follow when 
 molten slag or lead are permitted to come in contact with 
 vessels or implements containing moisture, the superheated 
 steam thus generated blowing the hot metal with great 
 force for considerable distances (Figs. 83, 84, and 85). 
 At times considerable masses of molten metal may force 
 their way between the lids and the globe, and, owing to the 
 
 Fig. 83. — Man with eyesight destroyed and face badly disfigured by burns from molten metal. 
 
 physical phenomena of calefection, whereby the tissues are 
 separated from the metal by the sudden evaporation of the 
 fluid on the surface of the eye, a perfect mould of the con- 
 junctival cul-de-sac is formed, comparatively but little 
 damage being done to the contiguous structures. At other 
 times, however, the injurious effects of such explosions is 
 very great, and the author remembers to have seen a case 
 in the practice of a colleague where a large fragment from 
 
WOUNDS AND INJURIES 
 
 S49 
 
 Fig. 84. — In this case the babbitt metal completely covered one eye and if employee had 
 not been protected by this safety precaution, he would undoubtedly have lost both eyes, in- 
 stead of receiving but a slight burn about the face. 
 
 Fig. 85. — Glaaaea used by workmen pouring babbitt. 
 
250 
 
 HYGIENE OF THE EYE 
 
 Fig. 86. — A foundry chipping yard, eyes of workmen properly protected by goggles. 
 
 
 
 p.. W-^^ '^m 
 
 
 "■ -^-^ 
 
 -;:■•■■■.«,. 
 
 
 Fig. 87. — Glasses used by wprkmen chipping wheels; also burlap guard to catch flying chips of 
 
 steel. 
 
WOUNDS AND INJURIES 
 
 251 
 
 a red-hot chisel forging completely destroyed the eye of a 
 bystander. 
 
 Of all the various workmen engaged in the industries, 
 the most liable to ocular injury are chippers (Figs. 86 and 
 and 87) . Chippers are men who remove the rough surface 
 from steel castings which frequently remain after the molten 
 metal has hardened, this being accomplished either by a 
 hand chipper or by means of the more modern pneumatic 
 
 Fig. 88. — Man with hood of brass wire, standing before furnace. 
 
 implement. The fragments dislodged fly from the casting 
 with great velocity and force, and frequently injure not 
 only the eyes of the chippers themselves, but those of their 
 fellow-workmen or the passerby. Goggles are imperative 
 for all those engaged in chipping or in the vicinity, and 
 screens composed of wire or burlap should be so placed that 
 they act as buffers to the flying particles. Flying scale is 
 frequently thrown off from the rolls of a blooming mill and 
 
252 
 
 HYGIENE OF THE EYE 
 
 employees engaged in this work should wear protecting 
 masks of fine brass netting (Fig. 88) . 
 
 When water and steam is turned into a water-gauge^ 
 with which all boilers are provided, the pressure at times 
 is great enough to burst the glass and to blow the fragments 
 
 Fig. 89. — Water gauge glass on boilers, protected with brass casting, having a small slit 
 in the front and back. The gauge of water can be viewed from the ground. There is an incan- 
 descent light placed at back of glass to reflect the stage of water. 
 
 into the face of the engineer observing the gauge. In a 
 recent year in Massachusetts seven men lost the sight of 
 both eyes and one workman that of one eye from the burst- 
 ing of such gauges ( Fig. 89 ) . This has been obviated by 
 providing the glass column with a protecting shield of 
 brass which covers the glass when turning steam and water 
 
WOUNDS AND INJURIES 
 
 253 
 
 into the gauge and is capable of being rotated to the side 
 when the danger of this act is over and it is necessary to 
 ascertain the registration of the water in the boiler. The 
 Xew York Central roads have installed an admirable model 
 of this device in their works, and no accidents to the eyes 
 have occurred from bursting gauges among their many 
 employees since it has been in use. 
 
 Pig. 90. — Glasses used by operator at emery wheel; also notice warning for men to wear glasses. 
 
 The emery wheel is a constant source of danger. When 
 operated at high speed, it may burst and its fragments kill 
 or injure workmen close at hand. Most serious are the 
 burns and scars inflicted upon the cornea of those who work 
 with unprotected eyes, by the dust given off from the wheel 
 while tools and instruments are being ground upon it. The 
 breaking off of fragments from the tools in the process of 
 
254 HYGIENE OF THE EYE 
 
 grinding provides, however, a still greater source of dan- 
 ger to the eyes, and many an eye has been blinded by these 
 flying particles of steel (Fig. 90). Many manufacturing 
 establishments now protect their workmen from injury 
 from bursting wheels by encasing them in hoods of steel, 
 and the eyes of the men from broken particles of wheel 
 
 Fig. 91. — Hammer — showing chip. 
 
 and from flying chips by shields made of heavy plate glass,^ 
 the transparency of the glass permitting the workman to 
 observe the tool he is grinding. Most wheels are also pro- 
 vided with exhaust connections from the rear of each hood 
 to a forced draft pipe, which carries away much of the dust 
 by a vacuum system. 
 
 Another frequent source of danger to the eyes, not only 
 
WOUNDS AND IXJUMES 255 
 
 in the industries but also in domestic life, is the breaking 
 of steel particles from the head of tools which have become 
 flattened over or '' mushroomed '' from long use (Fig. 91 ) . 
 
 DANGER 
 
 YOU ARE WARNED 
 
 AGAINST WORKING 
 
 WITHOUT PROPER 
 
 EYE PROTECTORS OR 
 
 WITH BATTERED TOOLS 
 
 GET PROPER TOOLS 
 
 AND EYE SHIELDS 
 
 FROM YOUR FOREMAN. 
 
 Fig. 92. — Warning placard posted in the workyards of the Tennessee Coal, Iron and 
 
 Railroad Company. 
 
 While mushrooming is especially liable to happen to cheap 
 tools, it may occur also in the best hand-wrought imple- 
 ments, for a hammering tool must be fairly soft to prevent 
 
256 HYGIENE OF THE EYE 
 
 its becoming brittle, and if used too long it will naturally 
 flatten out. The prevention of accidents from this source 
 consists in sending the tools to the blacksmith just as soon 
 as they begin to show signs of wear. The Tennessee Coal, 
 Iron, and Railroad Company has considered this danger 
 of sufficient importance to cause a warning placard to be 
 posted in their workyards (Fig. 92). 
 
 Some of the most serious and ofttimes hopeless cases 
 the ophthalmologist is called upon to treat occur from Mast- 
 ing operations^ either in mining or in excavating for founda- 
 tions, etc. Such accidents result either from the premature 
 explosion of cartridges with too short fuses, or by delayed 
 explosions, the injuries occurring when the workmen, after 
 what they suppose sufficient time has elapsed after the 
 charge has been fired, seek to investigate the failure of the 
 explosion. At other times, when a number of cartridges 
 have been fired by an electric current, the workmen clear- 
 ing away the debris caused by the explosion are seriously 
 injured by the delayed explosions of several of the cart- 
 ridges which had failed to go off at the initial charge. The 
 injuries to the eyes in such cases are frequently caused by 
 little bits of copper from the exploded caps of dynamite or 
 from fragments of rock, substances incapable of magnetic 
 attraction, and on that account extremely difficult and often 
 impossible to remove from the eyes. 
 
 Another source of injury to the eyes is from exposure 
 to an excessive amount of heat and light rays, emanating 
 from furnaces in which glass and metal are being subjected 
 to a temperature of great magnitude. In welding of metals 
 by the electric arc, the oxygen-hydrogen flames or some 
 similar high temperature medium, a temperature of from 
 4000° up to as high as 7500° F. is frequently attained 
 
WOUNDS AND INJURIES 257 
 
 ( Fig. 93 ) . The ultra-violet rays generated by this process 
 are extremely harmful to the eyes, inducing changes which 
 may lead to blindness. In some of the processes it is neces- 
 sary for the workmen in charge to gaze intently into the 
 furnace and watch for the change in color of the molten 
 mass which indicates that the desired transformation in its 
 composition has been attained. Workmen subjected to 
 such intensity of light and heat radiations must wear proper 
 
 Fig. 93. — Mask used by operator to protect eyes and face while using electric welding 
 machine, the rays from which are very destructive. 
 
 protecting devices, and welders are usually equipped with 
 a complete metal helmet, which is absolutely light-proof, 
 except for the ocular apertures, which are covered with 
 certain forms of colored glasses. Mention will be made 
 later of the best kind of glass for this purpose (Fig. 94) . 
 
 Faultily constructed electiical appliances may be a 
 source of eye injury, blindness from cataractous forma- 
 tions in the lens sometimes occurring in eyes subjected to 
 the blaze of light from a short circuit. The author had 
 
 17 
 
258 
 
 HYGIENE OF THE EYE 
 
 under his care a few years ago a workman in one of the 
 large coal companies of the State who had lost his sight 
 in this way, but who fortunately regained it after a success- 
 ful cataract operation (Fig. 95) . Venturesome electricians 
 occasionally essay to light a cigarette from an electric arc, 
 ofttimes with disastrous consequences. To avoid acci- 
 
 FiQ. 94. — Glasses used by open hearth employees to protect eyes while looking in open hearth 
 
 furnaces. 
 
 dents from electric flash, all switches, fuse-boxes, etc., 
 should be enclosed. 
 
 Bottlers of aerated waters and those engaged in their 
 distribution, such as bar-tenders and soda fountain attend- 
 ants, may suffer injury to the eyes by flying corks or by 
 fragments of glass from the bursting of a bottle. This 
 latter accident may be guarded against in machine bottling 
 in factories by properly placed wooden screens. 
 
WOUNDS AND mjURIES 259 
 
 As has been aptly put by GiiFord ^: " The largest con- 
 tingent of the industrial army is made up of agricultural 
 laborers, and in all but the large manufacturing centres 
 the majority of serious eye accidents occurs in this class. 
 As might be expected from the varied activities of the man 
 on a farm, the character of these accidents shows the great- 
 est diversity. These include quite a number of wounds 
 from flying steel occurring while the victims are hammer- 
 ing at their farm machinery. A lot of wire-fence injuries 
 result from running into or from being thrown into the 
 
 r 
 
 Fig. 95. — Electric cataract. 
 
 barbs, or perhaps more often from staples flying back when 
 the wires are being taken ofl" of fence posts. A coil of 
 tempered wire is a very treacherous thing. The ends have 
 a way of springing about in an entirely incalculable man- 
 ner, a fact which every one handling wire should keep in 
 mind. Then come the botanical injuries, of which the 
 typical ones are superficial, but ragged wounds of the cornea 
 
 ^ " Industrial and Household Accidents to the Eye," Harold 
 Gifford, M.D. Conservation of Vision Series, Pamphlet II, Amer- 
 ican Medical Association, Chicago. 
 
260 HYGIENE OF THE EYE 
 
 from blades of corn or beards of wheat, and the more deadly 
 penetration by thorns and weed stubs, which more com- 
 monly occur to children. Wood-chopping injuries are also 
 typical and common; the dangei- to the bystanding child 
 being greater than to the man who wields the ax. Horse 
 and mule kicks furnish a considerable number of the eye 
 injuries on the farm, and this is one of the rare forms of 
 standard eye injury which would generally not be pre- 
 vented by the use of spectacles. Kicks from cattle rarely 
 injure the eye, on account of the limited vertical displace- 
 ment of the animals' hoofs. 
 
 " A fairly numerous list of eye accidents belong to what 
 may be termed household injuries. An enumeration of 
 some of the most typical of these may do some service in 
 the way of prevention. Chips of steel are not infrequently 
 driven into the eye through the attempt of some house- 
 holder to open a box by driving a hatchet under the lid with 
 a hammer. This combination of hammer and hatchet is 
 particularly deadly, because, on account of the relatively 
 large mass of the pieces of metal employed, the chips which 
 are broken off the edges fly with great velocity. This dan- 
 ger should be kept in mind, and if it seems necessary to 
 drive a hatchet or ax into a crack, the danger can be averted 
 by interposing a piece of wood between the two surfaces of 
 metal, or by using a heavy stick of wood instead of a 
 hammer. The attempt to drive a nail into a hard plank, on 
 the part of a novice, not infrequently results in the nail 
 flying back so as to injure the eye. Many an eye is lost 
 by the chopper of kindling-wood, one end of the stick 
 struck at right angles being frequently thrown up with 
 great violence. Striking the eye against some projecting 
 corner of furniture while the victim is going about in the 
 
WOUNDS AND INJURIES 261 
 
 dark is a common cause of household eye injury. This 
 is most apt to occur through the patient's stooping over in 
 the dark and bumping his eye on a projecting chair-post. 
 These injuries frequently cause entire loss of sight. Every 
 one going about in the dark should hold the hands six inches 
 or so in front of the eyes. These injuries are also a warn- 
 ing to eliminate sharp corners on tables, as these are of just 
 the right height to put out the eyes of the active child. 
 
 " Accidents with household chemicals are not uncom- 
 mon ; a bottle of ammonia, or some strong acid, or a can of 
 concentrated lye being spilled into the eyes while being 
 lifted down from some shelf. Even when chemicals are put 
 away tightly corked the cork frequently goes to pieces 
 under their influence, so that after being set away for 
 some time, some of the contents easily escapes when the 
 bottle is slightly tilted. This should lead to the enforce- 
 ment of a rule requiring all such chemicals to be put on a 
 high shelf, far back out of the reach of little children." 
 
 Methyl or Wood Alcohol Poisoning. — About 30 
 years ago, under the names of Purified Wood Alcohol, 
 Columbian Spirits, Colonial Spirits, etc., there was intro- 
 duced a dangerous product of the destructive distillation of 
 vegetable fibre, as a cheap and harmless substitute for ordi- 
 nary methyl or wood alcohol. Unfortunately, however, 
 the claim of harmlessness was not long maintained, for 
 cases of sudden death as well as of total and incurable 
 blindness began to multiply following the adulteration of 
 various popular medicaments with it. A careful investiga- 
 tion made by several prominent oculists about ten years 
 ago^ discovered 275 instances of death or blindness (some- 
 
 "^ Buller, F., and Wood, C. A. : " Poisoning by Wood Alcohol." 
 The Journal of the American Medical Association, Oct. 1-29, 
 1904, pp. 972, 1058, 1117, 1213 and 1289. 
 
262 
 
 HYGIENE OF THE EYE 
 
 times both) directly traceable to drinking or inhaling the 
 fumes of Columbian spirits or some other form of " de- 
 odorized " wood alcohol, such as occur in the adulterated 
 manufacture of Jamaica ginger, essence of lemon, cheap 
 whiske}^, etc. In addition to the visual symptoms, there 
 is usually acute abdominal pain, nausea, and vomiting, with 
 symptoms of cardiac depression. 
 
 Poisoning may also occur from inhalation of the fumes 
 of wood alcohol. This generally happens when the exhala- 
 
 FiG. 96. — Three bottles containing wood alcohol sold by druggists in New York City. 
 
 tions are mixed with rebreathed air, as in varnishing the 
 interior of beer vats, closets, etc. Susceptible subjects may 
 at times suffer from a single rub with alcohol containing 
 the deodorized mixture. Manufacturers of wood alcohol 
 should be compelled by law to so label their products that 
 even the most ignorant should learn of its poisonous char- 
 acter, but better still, its use should be prohibited (Fig. 96) . 
 So great is the danger to life and sight from wood 
 alcohol, that it would seem only sane to prevent its manu- 
 facture by law, especially as we now have "denatured alco- 
 
WOUNDS AND INJURIES 263 
 
 hoi," a grain or ethyl alcohol which by its cheapness 
 removes any excuse for the use of the poisonous methyl 
 alcohol. The admixture of various ingredients to de- 
 natured alcohol renders it unfit for drinking purposes, but 
 does not destroy its value for domestic consumption or for 
 the purposes of commerce. 
 
 Lead Poisoning. — On account of the diversified use 
 of this metal, poisoning from it is not uncommon. Per- 
 haps house painters working with lead paint suffer more 
 frequently than others, but printers handling type are af- 
 fected by it, as well as employees in lead factories of vari- 
 ous kinds. Hair dyes containing lead may evoke symp- 
 toms, and seamstresses, from biting off thread which has 
 been weighted with sugar of lead, may also be aifected. 
 Children have been known to develop lead poisoning by 
 sucking their fingers after handling fragments of wood 
 upon which the paint which formerly covered it had be- 
 come disintegrated by exposure to the weather. Ordi- 
 narily lead colic and other symptoms of poisoning by the 
 drug precede those of sight, but loss of vision leading in 
 some cases to total blindness may be the first sign. Gen- 
 erally prompt and efficient treatment will accomplish a 
 cure. 
 
 Illumination of Workshops. — An indirect, though 
 probably a not infrequent cause of accidents in our fac- 
 tories, is improper lighting of the workrooms. In many 
 establishments the lighting is so insufficient or the lighting 
 fixtures so badly placed, that workmen are either unable to 
 see the dangers which beset them, or their eyes, weakened 
 by the glare of unprotected lights, become incapable of 
 properly fulfilling their functions. 
 
 Dr. Nelson M. Black, of Milwaukee, who has made 
 
264 HYGIENE OF THE EYE 
 
 an extensive study of factory illumination, says in this 
 connection: "Factories should be well lighted, first be- 
 cause poor lighting injures the eyes, and second because 
 poor lighting detracts from the earning capacity of the 
 workmen and is an extravagance. Good lighting is eco- 
 nomical. Superior work can only be accomplished under 
 good lighting conditions, with which vision is preserved, 
 health is conserved, and factory output is increased from 
 8 to 15 per cent. Accidents are much less likely to occur. 
 The saving produced by good lighting will pay many times 
 over the cost of the installation of good lighting facilities. 
 The maximum number of accidents occur during the time 
 in which artificial light is used. A well-lighted factory is 
 more productive than a poorly lighted one. Bad lighting 
 is detrimental to eyesight and health. It is an extrava- 
 gance that factory owners can not afford." 
 
 The illumination of all rooms should be uniform and as 
 devoid of shadows as possible. Ordinarily the system of 
 indirect lighting which has so many admirable features, is 
 unadapted to this kind of illumination, as the ceiling and 
 walls of factories are necessarily darkened by smoke and 
 dirt and there is no reflection of the rays of light. Some 
 steady and sufficient form of direct lighting is therefore 
 indicated, and an overhead system which throws a diffuse 
 light upon all the machines is preferable to one which has 
 for its object the illumination of single lathes, wheels, etc. 
 
 To prevent and minimize the danger of ocular injuries 
 occurring in industrial occupations, several essentials must 
 be emphasized. In the first place, it should be the duty of 
 the employer to install in his workplace every form of 
 safety device which is on the market and which is adapted 
 to the peculiar form of his industry. Proper goggles should 
 
WOUNDS AND INJURIES 
 
 265 
 
 be furnished to the employees and a sincere and active cam- 
 paign of instruction instituted in the works, to instruct and 
 demonstrate to the workmen, the various dangers to which 
 they are subjected, and explanation and reasons given for 
 the safety devices which have been installed. An efficient 
 first aid service should be created, and so far as the eyes are 
 concerned, workmen should be absolutely prohibited from 
 offering any aid whatsoever in case of injury. Too many 
 eyes are lost in consequence of well-intentioned though mis- 
 
 FiG. 97. — Steel chip in lens. 
 
 directed attempts at removal of chips and cinders by 
 " handy men " about the shop. The author is convinced 
 from a long experience in treating workmen's eyes, that 
 dirty toothpicks and ends of matches, rusty pocket knives, 
 etc., are responsible for many hundreds of blind in his own 
 State alone. 
 
 In case of injury a protective bandage should be ap- 
 plied and medical aid sought at once. In the proper clean- 
 liness of the hospital, with its manifold appliances, the 
 skilled physician will detect that the chip which the work- 
 man had thought had only grazed his sight or had dropped 
 
HYGIENE OF THE EYE 
 
 from the eye entirely after inflicting a slight wound, has 
 in reality entered the globe (Fig. 97) . Under X-ray ex- 
 posure, the chip is located, a magnet applied, the foreign 
 body removed and the eye saved. / How different from the 
 
 Fig. 98. — Patient in position before giant magnet. 
 
 fate of an eye that has been scraped by a rusty knife by a 
 comrade, allowed to become infected, and is lost in a few 
 hours from suppuration (Figs. 98, 99, and 100). 
 
 Placards graphically describing the dangers of injuries 
 
WOUNDS AND INJURIES 267 
 
 to the eyes in the various occupations in which they are en- 
 gaged, printed in the languages of the workmen, should be 
 hung in prominent positions in the works. In addition to 
 these sources of information, the foreman or others in 
 authority should give explanatory and admonitory talks 
 to the workmen at frequent intervals, and every effort 
 should be made to acquaint them with the danger of their 
 work. 
 
 With the employer thus engaged at no little cost and 
 
 Fig. 99. — Skiagraph showing foreign body in eye. 
 
 annoyance to himself to safeguard his employee, it seems 
 but just that the workman should wilHngly cooperate to 
 the best of his abihty and avail himself of the safeguards 
 which have been provided for him. Indeed, the exigencies 
 of the situation seem so great, that it does not seem un- 
 reasonable to attach some penalty in the event that proper 
 treatment is refused or postponed. 
 
 This would appear to be especially proper in the mat- 
 ter of wearing goggles, for the usefulness and effectiveness 
 
268 
 
 HYGIENE OF THE EYE 
 
 of this simple device to protect eyesight has now been 
 proven beyond gainsay. Thus the American Car & 
 Foundry Company has proven that the use of goggles has 
 
 Fig. 100.— Taking X-ray for supposed foreign body in eye. Head of patient in X-ray machine. 
 
 reduced accidents in their plant seventy-five per cent. It 
 is argued by some that the wearing of goggles in the event 
 of accident only jeopardizes sight the more, on account of 
 
WOUNDS AND INJURIES 269 
 
 the liability of injury to the eyes from the broken glass of 
 the goggles. As a matter of fact, however, this apparent 
 danger is without foundation, as may be judged by the 
 following evidence. There has not been a single case of 
 injury to the eyes from broken glass since goggles were 
 introduced into the shops of the New York Central Rail- 
 road. The American Steel Foundries Company collected 
 94 pairs of goggles, all with lenses broken from flying chips 
 of steel from their works during a period of 3 months, and 
 in every case the eyes had escaped injury. Had the goggles 
 not been worn, some of the eyes at least would have been 
 lost. In another large steel foundry where spectacles have 
 been worn since 1911, 48 pairs of goggles were collected in 
 one month with lenses broken by flying pieces of steel ; 297 
 pairs were gathered among the several foundries covering 
 a period of six months. During this entire period not one 
 serious eye accident occurred.^ 
 
 Furthermore, in an experience of nearly 25 years, dur- 
 ing which the author has treated many hundreds of eyes 
 injured in industrial establishments, chiefly in his service 
 at the Wills Eye and Howard Hospitals, of Philadelphia, 
 he does not remember to have seen a single eye injury from 
 a broken goggle, nor can he recollect having observed 
 similar accidents in the practice of any of his colleagues. 
 Manufacturers of goggles are exceedingly careful to obtain 
 a proper tensile strength of glass and frame. The author 
 is informed, for example, that one of the tests applied con- 
 sists in dropping a hardened steel ball five-eighths of an 
 inch in diameter, 20 inches from an electric magnet directly 
 
 * This information was derived from a statement submitted 
 to the author by the National Association for the Prevention of 
 BHndness. 
 
270 HYGIENE OF THE EYE 
 
 upon the surface of the lens, without permitting the latter 
 to rest on any support other than its own frame. The 
 lenses subjected to this test will withstand 85 blows of this 
 kind without breaking, and the construction of the frame 
 is such that in the event of a breakage occurring, the 
 frames tend to push the broken glass away from the eyes 
 instead of allowing it to be pressed in. 
 
 The perfect goggle has not yet been made. It is true 
 that there are a large number of quite satisfactory goggles 
 on the market, which serve the purpose admirably of pro- 
 tection against such accidents as are caused by flying frag- 
 ments of steel, etc., for all that is necessary under such 
 conditions is a glass of sufficient strength to resist the im- 
 pact of the foreign body, and wire or leather-screened sides 
 with small apertures provided permitting of some cir- 
 culation of air, to prevent the entrance of chips from the 
 side. To save the eyes from injury from chemical acci- 
 dents and those from molten metals, greater protection is 
 necessary, and some form of transparent medium other 
 than glass which will not become fogged or steamed when 
 subjected to heat and gaseous fumes. 
 
 A special form of goggle is necessary when the eyes are 
 exposed to the action of intense heat and light rays, such 
 as occurs in oxy-acetylene welding, etc., on account of the 
 injurious eff*ect not only of the heat, but also of the 
 ultra-violet rays generated in such processes upon the eyes. 
 This has been accomplished in the past by the use of glasses 
 that absorbed the infra-red or heat radiations. The objec- 
 tions to this method are — first, that it has been found im- 
 possible to make a glass that would absorb sufficient of the 
 dangerous infra-red or heat radiations at one end of the 
 spectrum and the ultra-violet or chemical rays at the other 
 
WOUNDS AND INJURIES ^271 
 
 without cutting down the useful and harmless visible light 
 to such an extent that it was extremely difficult for the 
 workman to see his work ; second, that the glass by absorb- 
 ing heat radiations soon becomes intensely hot and then 
 gives out heat radiations itself, thus defeating the object in 
 view. 
 
 Quite recently, Professor Pfund, of Johns Hopkins 
 University, conceiving the idea of getting rid of the infra- 
 red or heat radiations by reflection, devised the lens which 
 bears his name and which is made as follows : A flat piece 
 of Sir William Crookes, or other glass of like nature, is 
 coated with an almost infinitely thin layer of 22 karat gold. 
 This gold layer being extremely delicate is protected by a 
 flat piece of hard white crown glass. According to Pro- 
 fessor Pfund, the action of the combination is as follows: 
 all of the radiations, except the extreme ultra-violet, pass 
 freely through the hard white crown glass. Encountering 
 the gold layer, the ultra-violet and visible radiations up to 
 about the middle of the red, pass without difficulty between 
 the little particles composing the gold atoms. At about the 
 middle of the red the light waves become too long to pass 
 between these little particles and rebound or are reflected. 
 Thus half of the red and practically all the infra-red or 
 heat radiations or waves are reflected or thrown back. The 
 ultra-violet and visible radiations or waves which have 
 passed through the gold layer encounter the Sir William 
 Crookes glass, which allows the visible light to pass freely 
 but absorbs the ultra-violet. Thus we have disposed of the 
 infra-red or heat waves by absorption, and have passed the 
 visible. This visible light can be regulated by varying the 
 thickness of the gold coating. As regularly made the coat- 
 ing is of such thickness as to pass 25 per cent, of the visible, 
 
272 HYGIENE OF THE EYE 
 
 but, if necessary, can be made to pass 75 per cent, of the 
 visible without seriously cutting down the efficiency in the 
 infra-red or heat end of the spectrum. As regularly made 
 it refracts 98 per cent, of the heat and is claimed by Pro- 
 fessor Pfund to be at least twenty times as efficient as the 
 best of the old style protecting glasses for the same trans- 
 mission in the visible spectrum. Proof of the practical 
 value of Professor Pfund's glasses still awaits, the author 
 believes, practical demonstration. 
 
 According to Dr. Nelson M. Black, of Milwaukee, 
 who has long been interested in this subject: "Glass in 
 which the color tends toward a yellow or yellowish green 
 affords the greatest protection from harmful rays. Such 
 glass is found on the market under the name of amber, 
 euphos, fieuzal, akapos and noviol glass. Even this glass 
 must have added to it, in the process of manufacture, a 
 dark smoked tint to reduce the intensity of the glare in 
 order that it may be used with comfort. 
 
 " Deep red glass is an effective protection against dan- 
 gerous light and is in general use in many industries. It is 
 usually combined with yellow, blue, or green and blue 
 glass. The objection to such a combination is the inability 
 to distinguish details and to see to get about, also the in- 
 creased weight caused by using two or more pieces of glass." 
 
CHAPTER XVII 
 
 EFFECT OF CERTAIN BEVERAGES AND DRUGS 
 
 The eye is susceptible to the action of a number of poi- 
 sons, which have been considered elsewhere, but there are 
 other substances not usually considered to be poisonous 
 which are in common use as stimulants and which may at 
 times exercise a most deleterious influence upon the eyes. 
 These are tobacco and alcohol. 
 
 Tobacco. — That not all users of tobacco suffer from 
 their eyes is apparent, as the use of tobacco is widespread 
 and ocular complications from the habit are but rarely 
 met with. Yet the experience of every eye surgeon is full 
 of instances where the abuse of tobacco has seriously im- 
 paired sight. For this unfortunate occurrence several con- 
 tingencies are necessary. First, adult life; secondly, the 
 absorption into the system of a large quantity of nicotine, 
 either by smoking or chewing or taking snuff to excess, 
 or by the prolonged handling of tobacco by workers in the 
 weed. A third factor of disturbed digestion, usually as an 
 indirect consequence of tobacco abuse and not infrequently 
 of an associated too free use of alcohol, is also not infre- 
 quently present. 
 
 The quantity of nicotine necessary for absorption be- 
 fore tobacco blindness or tobacco amblyopia, as it is called, 
 manifests itself, varies very greatly in different individuals. 
 Many escape who must be saturated with the poison, show- 
 ing that the degree of tolerance of tobacco varies in dif- 
 ferent individuals. Undoubtedly, as has just been sug- 
 gested, the state of the general health has much to do in 
 
 18 273 
 
274 HYGIENE OF THE EYE 
 
 maintaining this tolerance, large quantities of cigars being 
 consumed without provoking any symptoms, until a shock 
 or prolonged mental strain or other derangement of the 
 vital processes occurs, when thd visual disability at once 
 manifests itself. 
 
 The symptom first noted is usually an increasing diffi- 
 culty in reading. Soon not only the type appears blurred, 
 but distant objects as well appear fogged, the cloud being 
 always densest between the eyes and the object regarded. 
 The recognition of color is affected and those engaged in 
 occupations in which the recognition of color is requisite, 
 such as railroad men and pilots, are no longer able to dis- 
 criminate between red and green. Undoubtedly a number 
 of marine and railroad accidents have been caused by this 
 interference with the color sense, the affection coming on 
 so insidiously that the mariner or engineer who has previ- 
 ously had no difficulty in recognizing signals and has suc- 
 cessfully passed color blind tests has no suspicion that his 
 ability to discriminate between the colors of the signals has 
 been impaired. 
 
 Most poisons have a selective tendency in their effect 
 upon the structures of the body, and nicotine, in pursuance 
 with this general rule, damages those fibres of the optic 
 nerve which are connected with the macula lutea in the 
 retina, which will be remembered to be the seat of direct 
 and most acute vision, other portions of the nerve and 
 retina escaping. If the abuse of tobacco is persisted in, 
 total atrophy of these fibres follows and useful vision is 
 lost. 
 
 The prevention of tobacco blindness lies either in totally 
 abstaining from the use of tobacco or in moderation. There 
 are those, and perhaps this is true of the majority, who 
 
EFFECT OF CERTAIN BEVERAGES AND DRUGS 275 
 
 would be far better off physically if they did not use 
 tobacco in any form. Few gain the pleasure and solace 
 from its use which they crave and expect, and no one can 
 truthfully assert that tobacco is in any way a help to 
 health. The custom of using tobacco, however, is so wide- 
 spread that it is unlikely that hygienists will make much 
 headway in their efforts at its control by preaching absten- 
 tion and must be satisfied with the half-way measure of 
 moderation. But as so often happens, what is moderation 
 for one is abuse for another, so that any attempt at fixing a 
 definite amount of tobacco safe for daily consumption 
 would be futile. Under ordinary circumstances, however, 
 it would appear that smoking three or four moderately 
 strong cigars each day should suffice as a maximum, and if 
 this rule be adhered to it is unlikely that any trouble with 
 vision will result. So much is certain, that once the symp- 
 toms of amblyopia from tobacco manifest themselves, there 
 can be no hope of effecting a cure until the use of tobacco 
 has been stopped altogether. Added to this essential, care 
 must be given to the general health, and all other stimu- 
 lants, such as whiskey, which may act deleteriously upon 
 vision, must be prohibited. After a sufficiently long period 
 has elapsed to peiinit the tissues of the optic nerve to re- 
 gain their vigor and to allow for the elimination of the 
 poison of nicotine from the system, it is sometimes safe 
 to permit of a continuance of smoking under strict 
 curtailment. 
 
 Alcohol. — Alcohol, and we are now speaking not of 
 wood or methyl alcohol, that form of alcohol which is used 
 in the arts and whose injurious effects upon the eyes we 
 have already noted, but of ethyl alcohol, the essential prin- 
 ciple contained in beer, wines, and liquors, and other in- 
 
276 HYGIENE OF THE EYE 
 
 toxicating beverages, has a two-fold action upon the eyes. 
 When taken in toxic dose, that is to say, when enough 
 whiskey or beer is imbibed to produce drunkenness, the 
 accompanying double vision and: uncertainty of the posi- 
 tion of things is induced by the action of the alcohol on 
 the nerve centres controlling the movements of the muscles 
 of the eyes, just as the muscles of locomotion are affected. 
 As soon as the effects of the spree are gone, however, vision 
 clears, and no permanent danger to sight remains. 
 
 Steady and excessive drinkers, however, occasionally 
 develop a form of blindness or amblyopia very similar to 
 that which follow^s the abuse of tobacco; indeed, the two 
 often go hand in hand, for heavy drinkers are often heavy 
 smokers and vice versa, for the habitual smoker often 
 craves liquor in some form to stimulate his heart which 
 has been depressed by nicotine. Like the disturbance of 
 vision from tobacco, the cloudiness from alcohol occurs only 
 in those who have long indulged themselves in the exces- 
 sive use of the stimulant, and usually manifests itself only 
 after the general health has been impaired by their ex- 
 cesses. The same fibres of the optic nerve are involved 
 as in tobacco amblyopia, and the only hope of amelioration 
 is complete abstinence from the use of alcohol in any form. 
 
 The avoidance of this form of visual disturbance con- 
 sists, naturally, in the temperate use of all kinds of bever- 
 ages containing alcohol, particularly those, such as whiskey 
 and brandy, which contain large percentages of this poison. 
 One attack should determine strict abstinence for life, for 
 a recurrence is more likely than after tobacco amblyopia 
 and a complete cure more difficult to obtain. 
 
 Tea, Coffee, and Chocolate. — In rare cases, due to 
 the absorption by the body of poisonous substances con- 
 
EFFECT OF CERTAIN BEVERAGES AND DRUGS 277 
 
 tained in them, the excessive use of tea and coffee has 
 caused partial blindness. Fortunately, such visual disturb- 
 ances are rare. JNIore common are those which arise from a 
 general impairment of digestion, in certain individuals who 
 possess what is termed an idiosyncrasy for these substances, 
 and which is seen oftener from drinking chocolate, when 
 certain visual phenomena appear which are akin to those 
 already described under migraine, i.e., flashes of light, 
 motes, half vision, etc. Naturally, individuals with such 
 an idiosyncrasy should abstain entirely from these bever- 
 ages and the baneful effects from the excessive use of tea 
 and coffee should be combated by temperance in their 
 consumption. 
 
 Drugs. — The excessive use of certain drugs may be 
 injurious to vision. Mention can be made here of only the 
 most common. Blindness from quinine usually occurs in 
 malarial districts, whose population are accustomed to tak- 
 ing large quantities of the drug without medical super- 
 vision. The loss in vision is generally accompanied by 
 other symptoms of quinine poisoning, viz., ringing in the 
 ears, dizziness, fulness in the head and at times stupor 
 or delirium. Blindness may be immediate, or come on 
 gradually. The loss in sight may be so pronounced that 
 not even a flash of light may be perceived when held close 
 to the eyes. At other times, there may be but a moderate 
 obscuration of surrounding objects. After some days or 
 even weeks of blindness, vision gradually returns, though 
 very rarely to anything like full acuity, the field of vision 
 being much compromised by the disturbance of optic nerve 
 and retinal tissues occasioned by the overdose of the drug. 
 
 As the toxic dose of quinine varies for different indi- 
 viduals and under various circumstances, no fixed amount 
 
278 HYGIENE OF THE EYE 
 
 can be stated as being fatal to sight ; it behooves all, there- 
 fore, to be cautious in the amount they consume, and to 
 allow a sufficient interval to elapse to insure the absence of 
 unfavorable symptoms before the repetition of a 5 or 10 
 grain dose. 
 
 Overdose of salicylic acid, a drug much used to con- 
 trol rheumatic fever, acts upon the visual apparatus in 
 much the same manner as quinine, though recovery is 
 prompter and permanent danger rarer. 
 
 Various drugs used in the eocpulsion of worms from the 
 economy, such as male fern and santonin, the bases of 
 many proprietary worm cures, may also exert a deleterious 
 action upon vision and should only be administered under 
 medical supervision. Permanent loss of sight may follow 
 the ingestion of a poisonous dose of these drugs, being ac- 
 companied usually by purging and vomiting. 
 
 Iodoform, a powder used for antiseptic purposes on 
 raw surfaces, may be absorbed and produce visual dis- 
 turbances closely akin to those of tobacco. Loss of sight is 
 usually, however, preceded by other toxic signs, such as 
 diarrhoea, delirium, and fever, which should serve as cau- 
 tionary measures for the withdrawal of the drug. 
 
CHAPTER XVIII 
 
 COLOR-BLINDNESS 
 
 When a beam of light is permitted to pass through 
 a prism its rays are broken up into their component parts, 
 and according to the wave length of these parts, a luminous 
 band or spectrum is formed, which appears to the normal 
 eye to be composed of many colors, namely red, orange, 
 yellow, green, blue, indigo and violet. The red end of the 
 spectrum, corresponding to the refraction of the longest 
 light weaves, forms one end, and the ultra-violet or shortest 
 waves, the other end of the spectrum. Color, therefore, as 
 such does not exist in nature, but is a sensation excited in 
 the eye by light waves of different lengths. The inability 
 to distinguish all of the colors in the spectrum constitutes 
 color-blindness. 
 
 Although noted a hundred years previously, the first 
 accurate description of this condition was given in 1774 by 
 Dalton, an English chemist, who himself was color-blind, 
 and who published an accurate account of his own sensa- 
 tions. Among other peculiarities, he stated that he could 
 note no difference between the color of a green laurel leaf 
 and that of a stick of red sealing wax. To him the various 
 tints of the rainbow were narrowed down to yellow and blue. 
 Since. Dalton's time, numerous theories have been advanced 
 to explain color-blindness, the most important of these being 
 the Young-Helmholtz and the Hering theories. 
 
 Color-blindness may be total or partial, congenital or 
 acquired. To those who are totally color-blind, the world 
 appears as though it were tinted with different shades of 
 
 279 
 
280 HYGIENE OF THE EYE 
 
 gray. Total color-blindness is rare, but congenital partial 
 color defect is common, occurring in about 4 per cent, of 
 all males. In women it is rare, occurring in about ^/lo of 
 1 per cent. According to a well-known authority, color- 
 blindness is hereditary and is attached to certain families; 
 it may not be found in one generation, but reappears in the 
 next; all children will not be aiFected, the girls especially 
 escaping; when several children are affected it is traceable 
 to the mother ; the kind and degree will be the same for all 
 the cases in the family. In total color blindness, con- 
 sanguinity in the parents has been traced in 12.5 per cent, 
 of the cases. Partial color-blindness may vary greatly, but 
 the inability to differentiate between red and green is the 
 most common. 
 
 Acquired color-blindness may attend any disease within 
 the eye which causes retinal change or interferes with the 
 proper conduction of impulses from the retina to the visual 
 brain centres. The most common cause of acquired color- 
 blindness is disease of the optic nerve due to the immoderate 
 use of alcohol and tobacco, a fact of great significance, as 
 will be presently recognized. 
 
 It is essential in all cases of color-blindness that a dif- 
 ferentiation should be made between the acquired and con- 
 genital variety, for the first is amenable to treatment, the 
 latter incurable. The diagnosis is, as a rule, readily made, 
 for in the acquired form a searching examination will find 
 evidence of the existing disease within the eye and visual 
 acuity will also be lessened, whereas in the congenital 
 form, visual acuity is unaffected and the eyes themselves 
 are free from disease. 
 
 Color-blindness is of great significance, for it disquali- 
 fies for all occupations in which a proper discrimination 
 
COLOR-BLINDNESS 281 
 
 between colors is an essentiaL This includes many railroad 
 employees, all naval and marine officers, pilots and certain 
 classes of seamen, and all occupations in the arts which 
 require mixing pigments or matching colors. As a rule, 
 even those who are totally red-green blind are unaware of 
 the existence of this defect in their vision, and it is often 
 only after a most searching test that the lack in color sense 
 can be demonstrated. Although investigations and tests 
 had taken place at an earlier date, it was not until 1875 
 that Holmgren, a Swedish savant, instigated by a serious 
 railroad accident, perfected a method by means of which 
 deficiencies in the color sense might be detected. This test, 
 w^hich is still in common use, determines the ability of a 
 person to match various colors, a series of colored yarns 
 being used for this purpose. The set of worsteds employed 
 for this purpose consist of (1) three chief test colors, i.e., 
 a pale green, a light pink and a bright red, (2) a series of 
 match colors of lighter tints and hues which the color-blind 
 are apt to confuse with the test colors. The person under 
 examination is given one of the chief colors, and told to pick 
 out from the mass of worsteds spread out before him, all 
 colors which match it. The man with normal color sense 
 will have no difficulty in discriminating, but the color-blind 
 person will confuse red with greens and will add confusion 
 colors of various tints, such as drabs, grays, browns, etc. 
 The wool test is usually supplemented by a lantern test, 
 the lantern used for this purpose being constructed in such 
 a manner that a disc upon which are mounted the various 
 colors used in railroads and the marine, i.e., white, red, 
 green, and blue, may be superimposed over the light of the 
 lantern in rapid succession. As it has been found that the 
 color-blind are frequently able to differentiate between 
 
282 HYGIENE OF THE EYE 
 
 colors by their diiFerent intensities of brightness, the appa- 
 ratus is so arranged that a series of ground and smoked 
 glasses may be used to diminish the brilliancy of the vari- 
 ous test colors. The lantern is placed at 20 feet from the 
 observer, in a darkened room, and the observer required to 
 recognize and name colors of a size which subtend a visual 
 angle of 1 minute at that distance (see p. 19) . 
 
 Those with color-blindness, acquired from the abuse of 
 alcohol and tobacco, as well as from other causes, may at 
 times recognize colors correctly, provided the object upon 
 which the color is exposed is sufficiently large, but are never 
 able to meet the most stringent requirements of the lantern 
 test. Candidates for services rendering the testing of their 
 color sense a necessity are often dissatisfied with the Holm- 
 gren test, as they imagine failures are due to their in- 
 ability to name the various colors exposed to them, though 
 the test actually makes no such demand. They are, as a 
 rule, however, satisfied with the results obtained from the 
 more familiar exposure of the various colored lights in the 
 lantern. 
 
CHAPTER XIX 
 
 THE BLIND. BLINDNESS FROM AN ECONOMIC 
 AND SOCIAL POINT OF VIEW. THE EDUCA- 
 TION AND EMPLOYMENT OF THE BLIND 
 
 By O. H. Burritt, M.A. 
 
 principal, pennsylvania institution for the in- 
 struction of the blind, philadelphia, pa. 
 
 In the preceding chapters all the emphasis has been 
 placed, as it should be, upon doing everything possible to 
 conserve vision. But when everything kno^vn to science 
 has been done to prevent blindness, disease and accident 
 will still take their toll and it will be the sad duty of the 
 oculist to tell the fond mother that her little one will never 
 see again ; or perchance a strong man that he must prepare 
 himself for oncoming blindness. The purpose of this chap- 
 ter is not to minimize blindness — the loss of sight is always 
 a calamity — but to bring a message of hope and cheer to 
 those who must and can learn to live useful lives in spite 
 of blindness. We shall learn that total blindness need not, 
 does not, mean total despair. 
 
 Causes of Blindness. — As the causes of blindness 
 have been so fully considered in preceding pages, mention 
 need be made here of only one of the most common causes 
 of blindness in those of school age, i.e., between the ages of 
 five and twenty. The most prolific of all the causes of 
 blindness in children is that scourge of infancy, ophthahnia 
 neonatorum (babies' sore eyes) , which does its damage usu- 
 ally within three or four days after birth. The National 
 Committee for the Prevention of Blindness found that of 
 
 283 
 
284 HYGIENE OF THE EYE 
 
 3334 pupils enrolled during the school year 1914-15 in 30 
 
 residential schools for the blind, 740, i.e., 22 + per cent., 
 were the victims of ophthalmia neonatorum; and that 91 
 of the 602, i.e., 15 per cent., of the new admissions in 28 
 of these schools were blinded by this disease. It made blind 
 71 of 200 (35 per cent.) of the pupils enrolled in the 
 Philadelphia school December 1, 1916, and was the cause 
 of blindness of 27 per cent, of all pupils enrolled during 
 the past 25 years. A conservative estimate is that one- 
 fourth of all the children who reach our schools for the 
 blind are victims of this dire disease. And the horror of it 
 all is that blindness from this cause is almost wholly un- 
 necessary ; for it is preventable in almost every case. Pre- 
 vent blindness in this one-fourth of the pupils enrolled dur- 
 ing the last school year (1915-16) and we could close one- 
 half of the smaller residential schools for the blind in the 
 United States. Stop blindness from this one cause and 
 the reduction in the number of pupils would enable us to 
 close the schools supported by the following States: Cali- 
 fornia, Colorado, Connecticut, Florida, Georgia, Idaho, 
 Kansas, Louisiana, Mississippi, Missouri, Montana, Ne- 
 braska, New Mexico, North Dakota, Oklahoma, Oregon, 
 South Carolina, South Dakota, Utah, Washington, West 
 Virginia, Wisconsin, and Vermont. And as the annual 
 per capita cost of educating a blind child in a residential 
 school is now easily $350 in excess of that of educating a 
 seeing child, the annual saving to the tax payers of the 
 United States in the case of those children who are un- 
 necessarily blind from this single cause would be at least 
 $430,000. 
 
 Number of Blind Persons. — No accurate statement 
 as to the number of blind persons in any unit of govern- 
 
THE BLIND— EDUCATION AND EMPLOYMENT 285 
 
 nient can be made. That such information is lacking when 
 so much attention is given to the collection of statistical 
 data concerning every sort of enterprise is due to two prin- 
 cipal causes : the lack of a generally accepted definition of 
 blindness and of an accurate method of enumerating our 
 blind population. According to the exact and scientific 
 definition of the oculist, only he is blind to whose brain the 
 optic nerve conveys not even the sensation caused by a ray 
 of light. If this definition be accepted, the number of blind 
 is small indeed. But for the determination of such prac- 
 tical questions as education and employment, we must in- 
 clude in any enumeration of the blind those who have light 
 perception, see shadows or have varying degrees of defec- 
 tive vision. There is substantial agreement among oculists 
 that children who possess not more than one-tenth normal 
 vision should be taught by the methods used in the educa- 
 tion of the blind ; and this definition of blindness is generally 
 accepted by educators of the blind. If blindness be thus de- 
 fined the number of blind persons will be very much larger 
 and the ratio of the blind to the general population will be 
 perhaps as 1 : 2000. If we accept the figures of the United 
 States census of 1910, the ratio for the entire country is 
 approximately 1 :1600; for the State of Pennsylvania, 
 1 : 1700. 
 
 Classification by Age axd Sex. — The Xew York 
 State Commission on the Adult Blind in 1903, classifying 
 the 6008 persons returned as blind by the United States 
 census enumerators of 1900, found that of each 100 of the 
 l)lind population 10 were under 21 years of age; 23 were 
 between 21 and .50; 14 between .50 and 60; and .53 over 60 
 years of age. Other studies seem to warrant the general 
 statement that in the United States of every ten blind per- 
 
286 HYGIENE OF THE EYE 
 
 sons one is under 20, four are between 20 and 60, and five 
 are over 60 years of age. Of every 100 blind persons ap- 
 proximately 55 are men ; 45 women. 
 
 1 
 
 Provisions for the Education, Employment and 
 Care of the Blind 
 
 In whatever phase of work for the blind he may be in- 
 terested, every American returns from a study of the pro- 
 visions for the blind of Europe with the feeling that the 
 lot of the blind in America is far better than that of the 
 blind in European countries. How varied and how gen- 
 •erous these provisions are, a mere enumeration of them 
 will show. For blind babies and children too young to 
 attend school, nurseries; for children of school age, resi- 
 dential schools and classes providing for the co-education 
 of blind and seeing; for able-bodied men and women of 
 working age, not only working homes where blind men 
 and women are segregated, but State commissions and 
 voluntary associations to aid and encourage cooperative 
 and individual effort with particular emphasis upon keep- 
 ing blind people in their own homes and communities ; for 
 those who desire to read, circulating libraries of embossed 
 books ; for the adult blind, home teachers who go from home 
 to home to teach reading and supply vocational instruction ; 
 and for the aged and infirm, homes for their care and com- 
 fort. While no two States make exactly the same provi- 
 sions for their blind citizens, there will be found at the 
 close of this chapter a brief but complete statement of all 
 the provisions made by public and private philanthropy 
 for the blind of the State of Pennsylvania. 
 
 Nurseries for Blind Babies. — In the United States 
 there are at least five nurseries or homes for blind children 
 
THE BLIND— EDUCATION AND EMPLOYMENT 287 
 
 under school age whose combined capacity is about 125. 
 In addition to these at least six States provide by law for 
 the instruction and maintenance of blind babies either 
 within their own borders in similar institutions for seeing 
 children or outside the State. The normal place for any 
 babe, seeing or blind, is at home with his mother, and no 
 blind child under five years of age should be deprived of 
 such care except for reasons that would obtain with seeing 
 children. These nurseries provide excellent care and 
 training for young children who need them as well as for 
 some who are older but backward or even feeble-minded. 
 
 The Education of Blind Children. — It is difficult 
 to say where and when the idea first took root that persons 
 without sight could be educated, but it is certain that it 
 received its greatest initial impulse from the determined 
 efforts in behalf of the blind of a son of a poor French 
 weaver, Valentin Haiiy, who had demonstrated by 1785 
 that the blind could be educated. Haiiy's work had a very 
 direct influence upon the beginnings of educational work 
 for the blind of this country. " I am convinced," said 
 Julius R. Friedlander, the first principal of the Pennsyl- 
 vania Institution for the Instruction of the Blind, " that 
 whenever more extensive experience and a better insight 
 into the ideas of the immortal Haiiy, relative to the instruc- 
 tion of the blind, shall prevail, his system will be everj^- 
 where introduced."^ The Philadelphia school shares with 
 the schools of New York and Boston the honor of taking, 
 about 1830, the initial steps to provide systematic instruc- 
 
 ■^ An address to the public at the First Exhibition of the Pupils 
 of the Pennsylvania Institution for the Instruction of the Blind, 
 at the Musical Fund Hall, Philadelphia, Thursday evening, 
 November 21, 1833. 
 
288 HYGIENE OF THE EYE 
 
 tion for the blind of the United States. The education of 
 the blind, as of all so-called defectives, had its beginnings 
 in private philanthropy, but an appeal was soon made for 
 aid from public funds. Accordingly, it was quite the cus- 
 tom to proceed with a small group of pupils to the capital 
 of the State and there before the law-makers to give an 
 actual demonstration of the possibilities for training those 
 who could not see. Appropriations usually followed such 
 demonstrations. The influence of the undertakings in 
 these three centres of population and culture spread rapidly 
 and the older and more populous States in quite rapid 
 succession provided residential schools for their blind chil- 
 dren. To-day there are forty- four residential schools in 
 forty States of the Union which were attended last year 
 (1915-16) by over 5000 students, the combined value of 
 whose plants was stated in 1914 to be $15,224,693. 
 
 All the older schools have passed through the experi- 
 ence of admitting both children and adults, apparently the 
 sole qualification for admission being that the applicant 
 should be blind ; but it was early learned that this practice 
 was unsound for moral as well as pedagogical reasons and 
 the almost universal practice now is to admit only chil- 
 dren between five and twenty-one years of age who are in 
 suitable physical, mental, and moral condition to profit by 
 the instruction afforded. The average age of the pupils 
 in one modern residential school of about two hundred 
 pupils is less than fifteen years. 
 
 The age at admission varies greatly for three principal 
 reasons : the variation in the age at which sight is lost ; the 
 ignorance of parents and people generally about provi- 
 sions for educating the blind ; and the reluctance of parents 
 to send their children away from home at a tender age. 
 
THE BLIND— EDUCATION AND ElVIPLOYMENT 289 
 
 Of the 35 new pupils received into the Philadelphia school 
 for the statistical year ending May 31, 1916, 16 were under 
 10 years of age; 10 were between 10 and 15 years; 7 were 
 between 15 and 20; and only 2 were over 20 years. 
 
 The length of time in school likewise varies greatly. 
 Determining factors here are the age of becoming blind, 
 general physical condition, mentality, ambition to learn, 
 and the attitude of the home toward culture. Of 35 pupils 
 discharged from the Philadelphia school for the statistical 
 year ending ^Nlay 31, 1916, 3 remained less than one year; 
 9 betw^een two and five years ; 9 between five and ten years ; 
 and 14 over ten years (Fig. 101). 
 
 In a well-conducted modern school for the blind in- 
 struction is organized under four principal departments; 
 physical, manual, literary and musical. And their impor- 
 tance is about in the order named. 
 
 Physical Training. — The blind child without train- 
 ing is usually angemic, under-developed, poorly nourished, 
 with flabby muscles and nervous habit movements. If his 
 blindness is the result of disease, his physical stamina may 
 have been lowered so that he is quite content to sit idle in a 
 rocking chair ; if, as is more likely, he still retains the desire 
 to share in the play and the varied activities of childhood, 
 he gets small encouragement from his brothers and sisters 
 or from seeing children of the same age — the blind boy or 
 girl does not fit well into the active play of seeing children ; 
 he is in the way. As blindness is most prevalent among 
 the poor and ignorant, either because of ignorance or imder 
 the stress of poverty parents fail to provide the physical 
 exercise necessar}^ for the child's growth and development ; 
 for it is now generally recognized that play and physical 
 activity are fundamental to mental no less than to physi- 
 
 19 
 
290 
 
 HYGIENE OF THE EYE 
 
THE BLIND— EDUCATION AND EMPLOYMENT 291 
 
 cal growth. And it is not uncommon for a mother to 
 admit that she seldom takes her bhnd child out with her 
 because " he attracts so much attention." 
 
 For these and other equally cogent reasons the first 
 problem in the education of the blind child is his physical 
 development. Accordingly, everything possible in the 
 school regimen is arranged to lay the foundation of his 
 education in the improvement of his physical condition; 
 regular hours for sleep, an ample supply of nourishing 
 food, an abundance of fresh air and sunlight, a liberal 
 amount of prescribed exercise, and sufficient time for free 
 play. 
 
 Upon admission his general physical condition is care- 
 fully and critically examined by specialists in medicine; 
 the household physician inquires into his general health, the 
 laryngologist looks to the condition of his throat and ears 
 and if he has adenoids or enlarged tonsils they are re- 
 moved, and the oculist makes a careful examination of his^ 
 eyes, and if he believes his health or his sight can be im- 
 proved by an operation he recommends it. 
 
 Recognizing its obligation to do everything possible to 
 improve the physique of its pupils, the management of a 
 modern school for the blind endeavors to provide as essen- 
 tial features of its equipment a gymnasium, an athletic 
 field, a swimming pool, and a bowling alley. There is little 
 in the equipment of gymnasium or playground to remind 
 one that the children who use the apparatus are deprived of 
 sight — in the gymnasium, horse, wall machines, parallel, 
 horizontal, and stall bars, trapeze, teeter ladder, giant stride, 
 climbing ropes, horizontal ladder, running track; on the 
 playground, swings, see-saws, horizontal bar, slide, and 
 merry-go-round. The wide cement border will attract the 
 
292 HYGIENE OF THE EYE 
 
 attention of the observant visitor who is paying his first 
 visit to the gymnasium of a school for the blind. In answer 
 to his query he will be told that its primary purpose is to 
 inform the sightless roller-skater or dancer that he is near- 
 ing the wall of the room; for the moment his foot passes 
 from the wood to the cement floor he knows that he is in 
 the danger zone and he immediatelj^ changes his direction. 
 Incidentally this border is a convenient and safe place for 
 placing the movable apparatus when not in use. 
 
 Swimming, always an excellent form of exercise (Fig. 
 102) is particularly beneficial to the blind in that in most 
 forms it forces the swimmer to throw his head back, thus 
 counteracting the tendency to round shoulders among blind 
 people. Under good instructors every boy who remains 
 in school two or three years and at least half the girls learn 
 to swim, some of them becoming quite expert in the several 
 varieties of strokes, in diving and in swimming under water. 
 
 Considerable individuality is shown among bowlers 
 without sight in the manner of getting their direction be- 
 fore throwing the ball; one runs keeping his left hand on 
 the ball rack; another stands still, getting his sense of 
 direction by running his left hand a little way along the 
 edge of the gutter; while a third, given his sense of direc- 
 tion by the voice of the lad at the foot of the alley, seems 
 to need no other guidance. Necessity being " the mother 
 of invention," these boys have given each pin a number, and 
 when the lad who is setting up the pins names the numbers 
 still standing, the sightless bowler knows exactly where he 
 should throw the ball. A record of 222 of a possible per- 
 fect score of 300 points made by a totally blind boy is proof 
 that blindness does not bar one from a form of exercise 
 which seems to demand sight. 
 
THE BLIND— EDUCATION AND EMPLOYMENT 293 
 
294 HYGIENE OF THE EYE 
 
 On the athletic field some of the activities of seeing boys 
 are equally open to blind boys without any special devices. 
 Among these are the standing ^broad jump, the standing 
 high jump, three successive jumps, and the hop, step, and 
 jump. Given a free open field, the blind boy can engage in 
 a contest in the running broad juriip, his distance being 
 measured from his " take off " to his landing point. A 
 totally blind boy can put the shot and throw the hammer 
 almost as well as the seeing lad of equal age and physical 
 development, the only special device necessary being a 
 half-circle made of wood. It is manifestly impossible for a 
 totally blind boy to engage in a foot race without some 
 device by which to give him his direction. The apparatus 
 that has been devised to make this possible is about the only 
 special device necessary in equipping an athletic field for 
 sightless boys. " The idea of this was borrowed from pic- 
 tures contained in the reports of the institution in Sydney, 
 New South Wales, and in Edinburgh, Scotland. A three- 
 strand twisted wire cable, as light as is consistent with 
 strength, is stretched breast high between well guyed end 
 posts one hundred and ten yards apart. The little sagging 
 towards the middle is of no consequence. The runner holds 
 in one hand a wooden handle attached by a short flexible 
 chain to a ring on the wire. As he runs the ring slips along 
 and both the feel and the sound it gives enable him to hold 
 his course. So far so good ; but how to afford a proper stop 
 at the one hundred yards mark was not ascertained until 
 we had stretched across the track at this place a fringe 
 made of hammock twine to strike the runner in the face, 
 much as the low-bridge indicator does the men standing on 
 top of moving freight trains. This fringe stop, which is 
 entirely satisfactory, covers the two parallel cables of our 
 
THE BLIND— EDUCATION AND EMPLOYMENT 295 
 
 running track. Starting as they always do from the same 
 end, Wind boys can practice running as much as they please ; 
 but in all real racing, one instructor starts a pair by pistol 
 
 Fig. 103. — One hundred vard dash. Start. 
 
 ■ Fi3. 104.— Finish. 
 
 shot while another instructor, standing at the one hundred 
 yards mark, times them with a stop watch" (Figs. 103 
 and 104).' 
 
 ^ Edward E. Allen in the Seventy-fourth Annual Report of 
 the Pennsylvania Institution for the Instruction of the Blind. 
 
296 HYGIENE OF THE EYE 
 
 Blind boys get a great deal of sport and much pleas- 
 urable exercise from a modified form of football. To in- 
 troduce the element of competition they usually choose 
 sides, seeing to it that each team contains an equal number 
 of totally blind boys and at least one with some sight. When 
 it has been determined by lot which side shall " kick off " 
 from the centre of the field, the efforts of each team are 
 directed toward kicking the ball over the goal of the oppos- 
 ing team. To prevent the ball from passing over its goal 
 the team depends chiefly upon their team mate who has 
 sufficient vision to see the ball when in motion, although the 
 captain has directed his sightless team mates to stand at 
 possible strategic points with the hope that the opposing 
 player who, four chances out of five, is unable to see where 
 any member of the rival team is standing, will chance to 
 kick the ball against one of them who thus contributes what 
 he can toward the stopping of the ball. But the totally 
 blind player contributes his major share to the team work 
 by kicking the ball which he oftentimes does as well as, 
 and sometimes better than, his team mate with some sight. 
 The number of times each team kicks the ball over the 
 goal of the other, within the time limits, determines the 
 final score. 
 
 The Training of the Hand. — As the hand must do 
 duty for the eye, particular emphasis is laid at all times 
 upon the training of the hand. This training is begun 
 among the younger children by making large use of the 
 kindergarten occupations. Clay modeling and drawing, 
 which blind children do with upholsterer's brass-headed 
 tacks on '' cushions " filled with excelsior and covered with 
 denim, are particularly valuable because they enable the 
 child to express his ideas of objects which he has studied; 
 
THE BLIND— EDUCATION AND EMPLOYMENT 297 
 
298 HYGIENE OF THE EYE 
 
 paper folding and cutting patterns with blunt pointed 
 scissors; weaving with strips of wood about three-eighths 
 of an inch wide with half -inch skirt braid as warp ; string- 
 ing kindergarten wooden beads on heavy shoe laces fol- 
 lowed by the stringing of nature materials, such as cran- 
 berries and various kinds of garden seeds ( after soaking in 
 water) ; sewing with shoe laces through holes one-fourth 
 inch in diameter, followed by the use of coarse blunt 
 worsted needles with large roughened holes through heavy 
 cardboard — an unconscious but valuable training for finger 
 reading ; raffia for winding over a firm foundation, making 
 such ob j ects as napkin rings and picture frames ; and reed 
 basket making, made possible for younger children by the 
 introduction of wooden bottoms for baskets and trays — 
 these are the principal occupations by which the hands of 
 the little blind child are trained during his first years at 
 school. To work of this kind, so fundamental in all his 
 education and so vital in his subsequent employment in the 
 development of facility in the use of his hands, he should 
 devote at least one-third of his time in the school-room 
 (Fig. 106). 
 
 With this foundation the blind girl begins her course 
 in the manual arts, which includes hand-sewing, knitting, 
 crocheting, and machine sewing. In some schools girls are 
 taught to cane chairs with the double purpose of securing 
 a greater variety of manual occupation and of utilizing it 
 as a means of contributing towards their livelihood after 
 leaving school ; for under favorable conditions blind women 
 have been able to earn very creditable amounts from this 
 handicraft. Some learn to weave rag carpet. In a few 
 schools the course in manual occupations includes also 
 working in wood with the simplest tools. No course in 
 
THE BLIND— EDUCATION AND EMPLOYMENT 299 
 
300 HYGIENE OF THE EYE 
 
 manual training for blind girls is complete without in- 
 struction in the elements of domestic science or home keep- 
 ing. Where the school is built on the cottage plan, the 
 ideal course combines the theoretical instruction of the class- 
 room with the practical application of such instruction in 
 the necessary daily routine of the life in the cottage ( Fig. 
 107). 
 
 For the training of the hand of the boy a thorough 
 course in manual training is provided of which the chief 
 element is working in wood, or wood-sloyd. This course 
 should extend over at least four years of his elementary 
 course. By it he is laying the foundation for his life 
 career; these are the years during which his muscles are 
 most responsive to training; no subject in the school cur- 
 riculum is of more importance to his success in life. But 
 the training of the hand must not cease after four years of 
 manual training. Our problem is to provide sufficient 
 variety of training to hold the boy's interest that he may 
 continue to develop facility with his hands. So caning is 
 introduced at the appropriate time and instruction in this 
 manual occupation proceeds simultaneously with wood- 
 sloyd. By this time his capabilities along manual lines are 
 sufficiently known to guide the teacher in planning his 
 subsequent hand training. If he has good use of his hands 
 and has shown in his general musical training some ability 
 to judge pitch, he is given a trial at piano tuning. If he 
 lacks ability along either line, he should not undertake to 
 prepare for tuning. The usual manual occupations re- 
 maining for him are weaving rag carpet and rugs and the 
 making of brooms. 
 
 Literary Department. — From what has been said 
 it should now be quite evident that the foundation of a blind 
 
THE BLIND- 
 
 EDUCATION AND EMPLOYMENT 301 
 
302 HYGIENE OF THE EYE 
 
 child's education must be laid in the upbuilding of his body 
 and in the training of his hand. But an essential element 
 in any school is a course of study and this exists in one 
 form or another in all schools for the blind. Instruction 
 is usually provided in nearly all subjects taught in the 
 public schools through primary, intermediate and grammar 
 grades, several schools maintaining kindergartens. Most 
 schools provide instruction in from one to four years of high 
 school subjects. A few of the more capable pupils are 
 encouraged and assisted in every way possible to supple- 
 ment the education obtained in a school for the blind by 
 continuation courses at normal school, college, university, 
 or school of theology. 
 
 Reading. — As an instrument for the acquisition of 
 knowledge through books, the ability to read is a prime 
 essential. Valentin Haiiy " was the first — ^of whom we 
 have any record- — who conceived the idea of systematically 
 teaching the blind to read by means of raised characters.^ 
 The story of the way in which Haiiy was aroused to pro- 
 vide for this need of the blind is so interesting and instruc- 
 tive and the results of his efforts for them have been so far- 
 reaching in their effects that it is reproduced here. 
 
 " In 1771 St. Ovid's Fair was the chiefest popular at- 
 traction. Daily at this time when the crowds were greatest, 
 one of the booths had been mounted by a certain Valindin, 
 an impressario of genius after his style, whose success had 
 marked these public shows. Valindin had gathered to- 
 gether a number of blind men, whom he had given in charge 
 of a crowd of rowdies. These fellows were so enthusi- 
 astically enjoying the sport that they would have demol- 
 
 3 " History of the Education of the Blind," by W. H. IlHng- 
 worth, p. 5. 
 
THE BLIND— EDUCATION AND EMPLOYMENT 303 
 
 ished the booths in their exuberance, so that it became 
 necessary to organize a cordon of guards for protection. 
 Valentin Haiiy saw the exhibition. He followed the 
 throng and here, depicted by himself, is the scene which 
 he beheld and the impression which it made. 
 
 " ' In the month of September, 1771, they had placed in 
 a cafe at St. Ovid's Fair, six men, chosen from those who 
 were reduced to the humiliating necessity of begging their 
 daily bread; and to attract attention and to excite public 
 sympathy, they employed an instrument which if the hearer 
 were gifted with a musical ear, and even more if he had a 
 tender heart, would drive him from the inharmonious 
 sounds, that were designed to gain a reward of talent. 
 These men had been grotesquely costumed in robes and 
 long-pointed hats. On their noses they had put huge paste- 
 board spectacles without glasses. Placed before a desk on 
 which were music and lights, they executed a monotonous 
 chant in which the tenors, the bases, and the violins all took 
 the same part. There was nothing to palliate the insult that 
 they had put upon these unfortunates, who were surrounded 
 by emblems of the grossest ignorance, as, for instance, in 
 placing behind their leader the expanded tail of a peacock, 
 and on his brow the headdress of Midas. 
 
 " ' Why was it that a scene so dishonorable to humanity 
 did not perish the instant of its conception? Why was it 
 that poetry and picture should lend their divine ministra- 
 tion to the publication of this atrocity? Ah! it was with- 
 out doubt, that the scene reproduced before my eyes, and 
 carrying into my heart a profound sorrow might inspire 
 and arouse my soul. Yes, I said to myself, seized by an 
 exalted enthusiasm, I will substitute the truth for this 
 mocking parody, / will make the Mind to read! I will put 
 
304 HYGIENE OF THE EYE 
 
 in their hands volumes printed hy themselves. They will 
 trace the true characters and will read their own writ- 
 ing, and they shall he enabled to execute harmonious 
 concerts/ " ^ 
 
 More than ten years passed before Haiiy was able to 
 reach the goal of printing in relief for the blind. All the 
 early efforts to provide an embossed type were directed 
 toward making tangible the simpler forms of type in gen- 
 
 abc 3 e/qfttj,k.Liuao 
 parstayw x-ij z 
 
 Fig. 108. — Facsimile of type used by Valentin Haiiy. 
 
 eral use by the reading public. So long as men with sight 
 worked at the problem, this was the logical thing. Haliy's 
 adaptation was the following (Fig. 108) : 
 
 The first alphabets used in the American schools were 
 some form of " line type " which were simply modifications 
 of the ordinary fonts used by printers. Two forms were 
 
 ^ " The Blind as Seen Through Blind Eyes," by Maurice 
 de la Sizeranne, p. 56. 
 
THE BLIND— EDUCATION AND EMPLOYMENT 305 
 
 perfected: one, in the Pennsylvania school, known as the 
 Philadelphia Line Type which retained the capital letters 
 and used rounded forms of small letters, in which was pro- 
 duced in November, 1833, the Gospel of Mark, the first 
 embossed book for the blind printed in America ; the other, 
 in the JNIassachusetts school, known as the Boston Line 
 Type, which discarded capital letters and introduced the 
 principle of angularity into the letters in the belief that 
 they were more tangible. These types continued in use 
 until a blind man, Louis Braille, by chance another son of 
 France, devised an alphabet by a purely arbitrary arrange- 
 ment of dots. The enormous advantage of a " dot " over 
 a " line " system as a medium of instruction lies in the fact 
 that it can be written as well as read, no practical means 
 having been devised for writing any line system. Braille's 
 system is based upon six dots arranged two horizontally, 
 three vertically, thus • J of which sixty-three combinations 
 are possible. This system was adopted in France, was in- 
 troduced later into England and somewhat later into the 
 L^nited States. Various modifications of this arrangement 
 have been devised, but the basic principle of Braille's cell 
 obtains wherever education for the blind is provided. One 
 modification, devised by another blind man, this time an 
 American, Joel W. Smith, in use by abovit one-half of the 
 schools in this country, sometimes referred to as '' revised," 
 sometimes as " scientific " Braille, but more generally 
 known as American Braille, is as follows (Fig. 109) : 
 
 Another modification of Braille's system, known as 
 Xew York Point, devised by Dr. Buss and perfected by 
 Mr. Wait at the Xew York (City) Institute is based upon 
 a cell only two dots high, thus : :, which is capable of in- 
 definite extension horizontally. This system was formu- 
 
 20 
 
306 HYGIENE OF THE EYE 
 
 AMERICAN BRAILLE 
 
 To write on a Braille tablet begin at the right; to read reverse th? sheet and 
 
 begin at the left. In either case the six points ( • • 1 of which the characters are 
 
 formed, are numbered from the top, 1, 2, 3, for the first vertical rov/, and 4, 5, 6, 
 for the second. 
 
 ALPHABET. 
 
 abcdef ghijklm 
 
 • • • •• •• •• • •••• • •• 
 
 • •• • •• •• •• • ••• • 
 
 • • • • • • 
 
 nopqrstuvwxyz 
 • • ••••••••• • • « • •• 
 
 • •• • • •••• ••• 
 
 •• •• • •••• *••• • 
 
 To capitalize a letter prefix to it points 3 and G ( • • / • 
 MARKS OF PUNCTUATION. 
 
 ■ ,;:.?!-()'- 
 
 • • • • 
 
 The apostrophe is point 4. The other marks, except the exclamation, are 
 formed of points 2, 3, 5 and 6. 
 
 When two or more initial letters requiring the capital sign occur together, the 
 space which separates words may be omitted; the period which follows the first letter 
 then becomes also the prefix, or capital sign, for the next; thus, 
 
 !• •• • F. R. S. 
 
 NUMERALS. 
 
 When alone or in combination the following letters, if prefixed by the numeral 
 
 sign ( • ] become numbers. 
 
 1234567890 
 
 • • •• •• • •• •• • • • 
 
 « • •• •• ••• •• 
 
 1 : • 46 : •: :* 235 ::••*. 
 
 •• •• •• 
 
 Fig. 109. — American Braille alphabet. 
 
THE BLIND— EDUCATION AND E^VIPLOYMENT 307 
 
 lated earlier than the xAmerican Braille and is used in fully 
 one-half of the schools on this continent. 
 
 Between these two dot types, the battle of supremacy 
 in America has been waged for a quarter of a century. For 
 about fifteen years a committee of capable blind people has 
 been working for a uniform type with the hope that an 
 agreement with the English can be reached so that there 
 shall be a uniform type for the blind of the English-speak- 
 
 Fig. 110. — Interlining Braille slate. 
 
 ing world. The world war has interfered with the prog- 
 ress of the work for uniformity of the committees appointed 
 in England and America, but it is believed that mutual 
 concessions will ultimately lead to uniformity. 
 
 Writing which can be read by the fingers is done by 
 means of a stylus with which the writer pushes the paper 
 into " pits " drilled into a metal base, the number corre- 
 sponding to the six dots of the Braille cell, the stylus in the 
 writer's hand being guided by cells punched into a metal 
 
308 
 
 HYGIENE OF THE EYE 
 
 guide. This method is somewhat slow, as it is possible to 
 make but a single dot at a time, but those who have good 
 use of their hands, with constant practice, write with re- 
 markable speed. A small machine resembling somewhat 
 a typewriter but with keys corresponding to the number of 
 dots in a cell has been invented by which the operator can 
 make an entire character at one stroke. By this it is possi- 
 ble to produce embossed characters with greater speed and 
 facility (Figs. 110 and 111). 
 
 Fig. 111.— Hall Braille writer. 
 
 Pencil writing can be learned by totally blind people if 
 sufficient time be given to it, but many educators believe 
 that it has insufficient value to warrant the time and effort 
 involved for one who has never seen to learn to produce 
 legible writing, particularly in view of the moderate price of 
 typewriters which can be easily mastered by blind people. 
 Pencil writing has been taught most systematically and 
 continuously in this country at the Perkins Institution now 
 located at Watertown, Mass. That one who has been 
 
THE BLIND— EDUCATION AND EMPLOYMENT 309 
 
 totally blind from early childhood can produce a perfectly 
 legible letter is shown by the reproduction of an invitation 
 
 dtr UowE nzf^dLjia LLuir 
 CQA-dLaLlij LyLviit^ u uu in 
 If c L JiEactii ai: a en. h.z- 
 
 rTLfc h. tnLTimcvL't -to, Irr 
 
 niLiLdLTUT, Pclr^iia^Tj 
 T I 1^ f k^ art ^ ua h.tc:)L 
 
 Fig. 112. — Facsimile of pencil writing in "square hand" by a totally blind girl, a pupil 
 of the Perkins Institution for the Blind, Watertown, ^lass. 
 
 written by a girl pupil of that school, blind since two years 
 of age, who has studied pencil writing about ten years 
 (Fig. 112). 
 
310 HYGIENE OF THE EYE 
 
 Languages, whether Enghsh, modern foreign, or 
 ancient classical, can be reproduced for finger readers. It 
 is only necessary to assign dot characters for various ac- 
 cents and modified vowels, or for the entire alphabet as in 
 the case of Greek, and the blind student can become as pro- 
 ficient a linguist as his seeing classmate. The chief ob- 
 stacles to a wealth of text-books and literature for the blind 
 are the cost of production and bulk of embossed books 
 which is referred to later in this chapter. 
 
 Mathematics in nearly all its forms is as possible for 
 blind as for seeing students. By means of an arbitrary 
 assignment of characters the ten arithmetical digits and 
 the signs of operation are provided for. In the same man- 
 ner the need is met for the additional characters necessary 
 for algebra and geometry and the higher mathematics. 
 Short processes in arithmetic and mental arithmetic are 
 most advantageous to the blind student and should be 
 utilized to the fullest extent. Some blind students have 
 done such notable work in mathematics as to seem to war- 
 rant the statement that the blind excel in this science ; but 
 the truth is there are about the same differences among 
 blind as among seeing students ; some excel in mathematics, 
 others in languages — it is a matter of individual taste and 
 capacity, a question wholly apart from the possession of 
 sight or the lack of it. 
 
 The elementary facts of form study and drawing can 
 be taught by special devices. One method is a home-made 
 *' cushion " ; a shallow box, whose sides are two or three 
 inches deep, is filled with hair or excelsior which is covered 
 with ordinary denim cloth. On this " cushion " the sev- 
 eral kinds and sizes of upholsterer's tacks are used for the 
 various kinds of lines. 
 
THE BLIND— EDUCATION AND EMPLOliMENT 311 
 
312 HYGIENE OF THE EYE 
 
 It is probably true that no subject in the curriculum 
 of all schools is so generally poorly taught as geography, 
 and this is no less true of schools for the blind. The de- 
 scriptive portions of this sub j ect are as easily taught to 
 sightless as to seeing pupils. But it is exceedingly difficult 
 if not impossible to convey, to those blind from birth or 
 early childhood who consequently have no visual images, 
 any correct notions of the graphical portions of the subject. 
 Outline maps are made on metal plates from which repro- 
 ductions upon paper are made in sufficient quantities that 
 each pupil can have one under his fingers, but it is doubt- 
 ful whether the pupil gets any very exact idea from these. 
 In this matter, however, he may be no worse off than the 
 seeing child who, it is well known, acquires singularly in- 
 correct notions from the map. Probably the most satisfac- 
 tory aids to map study in a school for the blind are the 
 dissected maps which enable the pupil to acquire more ac- 
 curate ideas of form and relative size. Maps can be drawn 
 by means of the special device for drawing, already de- 
 scribed, but the process is so slow and the results are so in- 
 commensurate with the labor involved that it possesses 
 doubtful value (Fig. 113). 
 
 History can be as easily taught blind as seeing pupils. 
 The chief difficulty is the limited number of books which 
 makes impossible any extended reading or research work, 
 except by the few who can afford to employ a reader. But 
 as blind people must get a much larger proportion of their 
 information through the ear than through the eye, some 
 acquire the habit of attention so that they are able to get 
 as much from one reading of a historical or literary passage 
 as many seeing people do from two readings. This power 
 is not, however, to be considered as inherent in blindness; 
 
THE BLIND— EDUCATION AND EMPLOYMENT 313 
 
 and in the blind as a class there are the same individual 
 diiFerences in the power of attention as among those who 
 see. 
 
 The facts of the various natural and physical sciences 
 can be acquired by blind pupils who can follow and even 
 themselves perform many of the simple experiments which 
 seem to require sight. Indeed, an enthusiastic teacher of 
 these sciences can give totally blind pupils a considerable 
 fund of information from clear and detailed description 
 of experiments which the teacher performs in the presence 
 of the class. 
 
 Typewriting is taught in most schools for the blind, 
 almost every make of machine being used and usable by 
 sightless operators. Shift-key machines are doubtless best, 
 as their keyboards are more compact and liability to errors, 
 due to striking the wi'ong keys, is reduced by nearly one- 
 half. The blind operator is entirely at home with the 
 " touch system " now generally taught in schools of busi- 
 ness ; for no other system is possible for him. Contrary to 
 popular belief, no special marking of the keys is necessary ; 
 he learns his keyboard precisely as does the seeing oper- 
 ator who learns the " touch system." Blind people can 
 and do learn to write almost without error. The typewriter 
 is the best means of communication between blind people 
 and their sighted friends. The ability to use the typewriter 
 well can be acquired by the expenditure of much less time 
 and effort than is necessary to be able to write legibly with 
 the pencil. Cheapness, simplicity of construction, dura- 
 bility, and portability are the chief desiderata in a type- 
 writer for the bhnd. The folding typewriter recently 
 manufactured is a boon to them. The chief if not the only 
 argument against the typewriter and in favor of pencil 
 
314 HYGIENE OF THE EYE 
 
 writing is the relative cost; everyone can be supplied with 
 pencil and paper, only the few can afford to own a type- 
 writer. But as second-hand and rebuilt machines can be 
 purchased at a nominal cost, this argument loses much of 
 its force. 
 
 It has been demonstrated that a blind person who pos- 
 sesses the other qualifications can do work in typewriting 
 that has commercial value, particularly at such work as type- 
 writing from dictaphone records. Probably no other school 
 in the world has developed so highly efficient a typewriting 
 department as the Royal Normal College for the Blind in 
 London, England. Several graduates of that school hold 
 positions in offices which they have won in competition 
 with seeing typists because of the superior excellence of 
 their work. A few totally blind operators are filling re- 
 munerative positions in this country. In order to attain 
 success one must be able to do almost perfect work and 
 be fortunate enough to secure a position where he is not 
 required to file correspondence, but can spend his entire 
 time at typewriting. 
 
 The Musical Education of the Blind. — It is popu- 
 larly believed that the blind are more musical than those 
 who see; but we are no more warranted in generalizing 
 about the musical abilities of the blind than about any other 
 characteristics or abilities popularly attributed to them. 
 So far as the pupils of our schools are concerned, the truth 
 is that the general educational value of music and its par- 
 ticular value to those whose channels of enjoyment and ap- 
 preciation are restricted by the lack of sight are recognized, 
 and the aim is to provide adequately for instniction along 
 musical lines. In a residential school the atmosphere is 
 saturated with music. There is choral and group singing, 
 
THE BLIND— EDUCATION AND EMPLOYMENT 315 
 
 singing at the daily prayer service, individual voice culture 
 for a few of the most talented, instruction in piano playing 
 and, for a few with special talent, in organ playing. Some 
 schools add to these instruction on the violin, guitar, and 
 other stringed instruments. Little wonder is it that in such 
 an atmosphere those who possess musical ability are dis- 
 covered and provided with the very best musical education 
 obtainable! ]Music is preeminently the one art in the en- 
 joyment and appreciation of which blindness is no handi- 
 cap. Here blind and seeing are on a plane of entire 
 equality. 
 
 The difficulties are infinitely greater in following music 
 as a vocation. A talented few become church organists; 
 but one must possess superior ability and must put forth 
 almost herculean effort to meet the demands made upon 
 an organist of a modern church. A conspicuous example 
 of a blind man eminently successful as a church organist 
 is the late David Duffle Wood, of Philadelphia, who, 
 though totally blind from early childhood, by the sheer 
 force of will coupled with musical ability, broke asunder 
 the bonds which his blindness imposed upon him and be- 
 came one of the most eminent musicians of the city in which 
 he lived. After securing his education at the Pennsylvania 
 Institution for the Instruction of the Blind, he became the 
 organist at St. Stephen's Protestant Episcopal Church, 
 which position he held for forty-six years, during twenty- 
 five of which he was its musical director. During much of 
 this time he was a member of the staff of one of the city's 
 best schools of music and he was in constant demand as a 
 teacher of the organ. 
 
 The moving picture theatre offers a wider field for 
 musical talent and more remunerative employment, and 
 
316 HYGIENE OF THE EYE 
 
 not a few successful organists have left the church organ 
 bench for this better compensating, if less dignified, field of 
 labor: but to succeed in this field one who is totally blind 
 must have the aid of a person with sight. A still larger 
 number become teachers of the piano; some in schools for 
 the blind, some as private teachers of seeing children. Sev- 
 
 FiG. 114. — Senior pupils teaching seeing pupils. At the clavier and piano. 
 
 eral schools now provide normal courses for those who have 
 the inclination and the ability to teach, in which the teacher 
 in training is instructed in the methods employed in teac-li- 
 ing seeing children and actually teaches them imder the 
 supervision of the experienced teachers of the music staff. 
 For blind people who possess the requisite ability, musical 
 
THE BLIND— EDUCATIOX .\XD EMPL0Y:\IEXT 317 
 
 appreciation, personality and perseverance, the profession 
 of music offers a field for useful and remunerative em- 
 ployment ( Fig. 114). 
 
 COEDUCATIOX OF BlIXD AXD SeEIXG IX PuBLIC 
 
 Schools. — What has been said so far about the education 
 of the blind has had reference to their training in resi- 
 dential schools, which was the only method in vogue until 
 the twentieth century. To the city of Chicago belongs the 
 credit of undertaking, in 1900, the experiment of educating 
 blind children in classes with those who see. This plan was 
 in operation during the school year 1915—16 in at least ten 
 cities in which there were enrolled 497 pupils. 
 
 The usual plan of conducting these classes is as follows : 
 A room, equipped with the special devices needed by blind 
 pupils, is placed in charge of a special teacher whose first 
 duty is to see that the pupil masters the devices that are 
 necessary for him to be able to use almost automatically 
 before he can go to the grade room, to which by his age and 
 attainments he belongs, and share in the recitations with 
 his seeing classmates. He must learn to read and to write 
 his dot type, to use his type slate ( a special device used by 
 the blind in arithmetic and algebra), and later to operate 
 a typewriter. As soon as he can read and wa'ite his dot type 
 he can take part in the recitations in reading, spelling, 
 language, geography, history, and similar subjects. One 
 important and arduous dutS^ of the special teacher is to see 
 that the blind pupil is provided with a reading book and 
 wherever possible with an embossed copy of all the material 
 used by his seeing classmates. The special teacher inter- 
 lines for the grade teacher his written work in language, 
 history, geography, etc. ; for everything must be done to 
 make the blind child a welcome member of the class, and 
 
318 HYGIENE OF THE EYE 
 
 one essential is that he add as little as possible to the duties 
 of the grade teacher having from forty to sixty pupils. As 
 he progresses he can save the time of both special and grade 
 teacher by using the typewriter for his " written " work. 
 As the assistance by the special teacher must be largely in- 
 dividual and as all of her pupils may belong to different 
 grades, the membership of these classes is usually restricted 
 to ten pupils. 
 
 While this method is still in an experimental stage it 
 is only fair to its advocates to say that the advantages 
 claimed for it have much to commend it ; it keeps the child 
 constantly among seeing children and in the normal atmos- 
 phere of his home instead of removing him for a time to a 
 residential school; it places the responsibility for his care 
 and support upon his parents; and it is more economical. 
 Obviously such a plan is possible only in the more populous 
 centres. 
 
 This plan, however, violates the two most fundamental 
 needs in the education of the blind which were stated earlier 
 in this chapter, in that it fails to make any adequate pro- 
 vision for the physical and manual training of the pupils. 
 Under this method, too, is lost all there is of value in hav- 
 ing pupils continually in a musical atmosphere, and it is 
 much more difficult to provide them with opportunities for 
 serious musical study. In other words, it so far provides 
 chiefly for the literary education of the blind and this it 
 seems to do well. In all fairness it ought to be said, how- 
 ever, that private associations interested in the experiment 
 have done what 'chey could to supply these needs and they 
 have succeeded admirably when the difficulties are fully 
 understood and appreciated. Altogether the plan has much 
 to commend it. Between those who advocate it and those 
 
THE BLIND— EDUCATION AND EMPLOYMENT 319 
 
 who favor the residential school plan there is no conflict; 
 rather the advantages of both methods are recognized and 
 the ideal arrangement in the minds of the leading advocates 
 of both is that which will give each child, who can possibly 
 avail himself of them, the advantages to be derived from 
 both methods. 
 
 The Higher Education of the Blind. — No institu- 
 tion for the higher education of the blind, corresponding to 
 Gallaudet College for the advanced training of the deaf, 
 has been provided and it is well that it is so. There is sub- 
 stantial agreement even among those who believe in the 
 advantages of the residential school that the period of resi- 
 dence in them should be shortened rather than lengthened. 
 Having been surrounded during ten or twelve of his most 
 impressionable years by his schoolmates similarly afflicted ; 
 having been thrown but little, if at all, upon his own re- 
 sources but accustomed to have all decisions made for him, 
 it is far better for him to secure his advanced training 
 among those who see. Where residential schools are situ- 
 ated near a high school the more capable pupils sometimes 
 attend the high school. A few of the more capable and 
 ambitious attend normal school, college, or university, 
 sometimes as resident students, sometimes as day pupils 
 from the special school. As only those are encouraged to 
 attempt advanced courses of training who are known to 
 possess superior ability, they usually maintain a very satis- 
 factory grade of scholarship. While the embossed print- 
 ing presses do what they can to supply for these students 
 advanced text-books in tangible type, they must usually 
 content themselves with embossed copies of their texts in 
 foreign languages and mathematics, relying upon readers 
 for the preparation of their lessons in other subjects. In 
 
320 HYGIENE OF THE EYE 
 
 order to aid these worthy young people in obtaining a higher 
 education, six states provide a limited amount of funds that 
 may be expended for a reader or for board and tuition or 
 for both. With his course satisfactorily completed the 
 young man or woman is still confronted with the problem 
 of making his way in the world. Nevertheless, the results 
 are highly encouraging: of 18 young men and women, 
 graduates of one of the three oldest residential schools re- 
 ferred to earlier, who had taken advanced courses of in- 
 struction, all are rendering useful service in their chosen 
 vocations and are self-supporting. Lewis B. Carll, an 
 eminent blind mathematician, stood second in the class at 
 Columbia College which his classmate, the late Seth B. 
 Low, led. Capable and worthy young people without sight 
 should receive every possible encouragement to secure a 
 higher education. 
 
 Embossed Books for Finger Readers. — ^When Haiiy 
 was providing his pupils with books in a tangible type late 
 in the eighteenth century, when the embossing presses in 
 Philadelphia and Boston began printing soon after the 
 opening of their schools, the process was a very slow and 
 expensive one. Nor was there any material advance in the 
 production of embossed literature until late in the nine- 
 teenth century. The adoption of the dot types was soon 
 followed by the invention of machines for producing metal 
 plates which are capable of embossing five characters per 
 second. Early in the twentieth century the rotary press 
 was adapted to printing from these embossed plates. These 
 two inventions have lowered the cost and increased the out- 
 put of literature for blind readers. But as the demand is 
 small and the books are bulky, the cost of paper and bind- 
 ing is disproportionately high. David Copperfield in one 
 
THE BLIND— EDUCATION AND EMPLOYMENT 321 
 
 dot type makes six volumes, as large as Webster's Un- 
 abridged Dictionary, which are listed at $3.50 each, making 
 the cost of a single copy $21.00. Since 1907 through the 
 generosity of Mrs. Matilda Ziegler, blind readers have been 
 furnished, free of cost, a monthly magazine containing sixty 
 to sixty-five pages. With the adaptation and perfection 
 of existing inventions to printing for the blind the cost of 
 production will gradually be lowered with a corresponding 
 increase in the amount of embossed literature. 
 
 Since 1879 the National Government has appropriated 
 $10,000 annually for the production of embossed literature 
 which has been distributed pro rata upon a per capita basis 
 to the various schools for the blind. The Howe Memorial 
 Press, an adjunct of the Perkins Institution at Water- 
 town, has an annual income of about $9000 which it may 
 expend in the production of literature and of apparatus; 
 and a number of schools and associations expend liberal 
 amounts from private funds. 
 
 The National Government conferred another great 
 boon upon its sightless citizens through the Department of 
 the Postmaster General by extending in June, 1904, the 
 franking privilege to embossed books sent by a library to 
 a blind reader or by a reader returned to the library. Prior 
 to this time books could be sent only by mail or by express 
 and the cost was so great as to be practically prohibitive. 
 Since 1904 there has been an enormous increase in the cir- 
 culation of embossed books and magazines (Fig. 115). 
 
 The Employment or the Blind. — Two questions 
 are usually asked by every interested visitor to a school for 
 the blind. His first question is, " What trades and pro- 
 fessions are open to the blind? " his second, " Can they 
 become self-supporting? " 
 
 He who lives and works among the blind and realizes 
 
 21 
 
322 
 
 HYGIENE OF THE EYE 
 
 P. V 
 
 
 ^1 
 
 s-q 
 
 fl.9 
 
 
 
 •5b-2 
 
 a « 
 
 '. a 
 
THE BLIND— EDUCATION AND EMPLOYMENT 323 
 
 how varied are their talents is almost tempted to reply in 
 answer to the first question: " There are few trades or pro- 
 fessions from which the blind are excluded." So many 
 factors enter into the problem that no general answer can 
 be given. In spite of its frequent use in speech and in 
 writing, the phrase " the blind " cannot be used in any 
 generic sense; there is no such concept as "the blind." 
 Persons without sight differ, precisely as those who see, in 
 capabilities, in tastes, in character — in short in all matters 
 that go to make personality. Some have keen intellects, 
 some are dull and almost unteachable; some have a great 
 deal of pride about their personal appearance, others are 
 wholly devoid of any appreciation of its importance ; some 
 have strong, sterling characters, others are weak, easily 
 led, and are wholly undependable. 
 
 The problem is further complicated by the age at which 
 sight is lost. It is one thing to continue the education of a 
 pupil who loses sight after his education is well begun; it 
 is quite another thing to give adequate training to one who 
 has never seen or who has become blind in early childhood, 
 which is true of three-fourths of those who reach our schools 
 for the blind. To aid the man who loses sight in adult 
 life with a background of years of experience in a world 
 where sight is the queen of the senses in readjusting him- 
 self to changed conditions ; to show him how he can live and 
 work as a blind man is not an easy task: but to provide 
 the best training and the wisest vocational guidance for 
 those who have never seen is a problem that sometimes 
 seems almost to defy solution. But in spite of the obstacles, 
 success has been won by the blind in many walks in life. 
 
 For those who lack initiative or who have found it im- 
 possible to succeed without guidance and assistance, in- 
 dustrial homes, which are factories or workshops with a 
 
324 HYGIENE OF THE EYE 
 
 boarding-house attachment, and workshops, which omit 
 the boarding feature, have been found necessary. A few 
 of these are supported by private funds, but nearly all of 
 them receive state or municipal aid. While this method 
 of furnishing employment seems necessary, many believe 
 that every possible effort should be made to keep blind 
 people in their own homes and communities. 
 
 Piano tuning has been found to be one of the most 
 remunerative employments for blind men who possess the 
 requisite ear and mechanical ability. Some find this trade 
 a stepping-stone to piano selling and later to successful 
 careers as proprietors of music stores (Fig. 116). 
 
 Others of less ability follow simpler and less remunera- 
 tive employments, such as the reseating of cane chairs, 
 hammock-making, tobacco-stripping, selling newspapers; 
 one man has accumulated a competence by selling peanuts. 
 
 Possessed of more ability, some have attained success 
 in business and professional life. Totally blind men and 
 women are successfully practising massage and osteopathy ; 
 a young woman, with the help of her mother as a reader, 
 reviews magazine articles and books before women's clubs ; 
 another teaches English to foreigners in a large cosmopoli- 
 tan city; still another teaches vocal music in the public 
 schools of two cities in a central western state. A totally 
 blind man has risen through piano tuning to the presidency 
 of a large piano business, maintaining stores in five Cana- 
 dian cities; another has acquired affluence as a real estate 
 dealer. Without sight men have attained success and use- 
 fulness in the law and the ministry. 
 
 Eminent among educators of the blind are the names 
 of two blind men, both knighted by the King of England 
 after forty years of eminent service, Sir Francis Campbell, 
 late principal of the Royal Normal College for the Blind, 
 
THE BLIND— EDUCATION AND EMPLOYMENT 325 
 
3^ HYGIENE OF THE EYE 
 
 London, England, and Sir Frederick Fraser, superintend- 
 ent of the Halifax (N. S.) School for the Blind; while a 
 not inconsiderable number are individual and class-room 
 teachers, teachers of music and of handicrafts in our schools 
 for the blind. 
 
 Blind men are representing their constituents in at 
 least three State Legislatures; the voters of a Minnesota 
 Congressional district recently elected a blind man as their 
 Representative in Congress. Thomas P. Gore, United 
 States Senator from Oklahoma, has been totally blind since 
 fourteen years of age, John E. Swearingen, South Caro- 
 lina's State Superintendent of Education, has been totally 
 blind from eleven years of age; and Sir Henry Fawcett 
 performed his greatest public service as England's blind 
 Postmaster General. 
 
 Nor has the field of literature been closed to the blind. 
 Milton produced " Paradise Lost " after he became blind; 
 though not entirely blind, Prescott and Parkman made 
 their exhaustive historical researches and did their writing 
 almost entirely through the eyes of their assistants, work- 
 ing against odds that would have disheartened most men; 
 totally blind from infancy, Fanny Crosby was the most 
 prolific hymn writer of the nineteenth century; and such 
 was his love for animals and nature and so keen were 
 his observations that Clarence Hawkes before his loss of 
 sight, at fourteen years of age, had laid the foundation that 
 enables him to give us accurate stories of animal life which 
 he does in charming language. 
 
 This list of successful blind people could easily be ex- 
 tended; but it is sufficiently long and varied to establish 
 the truth that, while blindness imposes a fearful handicap, 
 it does not prevent the attainment of the highest success 
 and usefulness in manv fields of human endeavor. 
 
Name 
 
 ). Ganey, Resident Supt 
 
 Mutes and Blind, J. S. Graves, 
 
 THE United States. — Corrected February, 1916. 
 
 Pupils 
 enrolled Superintendent 
 1914-1915 
 
 108.. F. H. Manning. 
 
 156 . .John H. Hinemon. 
 
 ition of the Deaf and Dumb, and 94. .L. E. Milligan. 
 
 5Und and Deaf Mutes 
 
 klassachusetts School for the BUnd 
 
 theBUnd 37. 
 
 46. 
 
 and the Blind 38 . 
 
 113. 
 
 f and the Blind 18 . 
 
 210. 
 ion of the Blind 143 . 
 
 135. 
 
 ation of the Blind 97 . 
 
 ation of the Blind 145 . 
 
 60. 
 
 150. 
 
 290. 
 173. 
 123. 
 
 78. 
 115. 
 
 18. 
 
 57. 
 
 45. 
 190. 
 119. 
 260. 
 
 26. 
 240. 
 
 91. 
 
 38. 
 230. 
 144. 
 
 93. 
 
 29. 
 233. 
 237 
 
 id 
 
 ion of the Blind 
 
 and Dumb, and the Blind 
 
 ation of the Blind . 
 
 [..._ _ 
 
 uction of the Blind 
 
 nstitution for the Blind 
 
 ation of the Deaf and Dumb, and 
 
 the Blind. 
 
 and Dumb and the Blind Colored 55 
 
 I the Blind 34. 
 
 Jlind 5. 
 
 the Blind 76. 
 
 r Colored Deaf and Blind 38. 
 
 id 54. 
 
 the Blind 83. 
 
 136. 
 
 and the Deaf and Dumb 
 
 otal enrolment, 1914-1915 4860 
 
 .W. K. Argo. 
 .George H. Marshall. 
 .A.H.Walker. 
 .G. F. Oliphant. 
 .W. E. Taylor. 
 .H. C. Montgomery. 
 .George S. Wilson. 
 .George D. Eaton. 
 .Isa A. Green. 
 .Susan B. Merwin. 
 .G. C. Huckaby. 
 
 .John F. Bledsoe. 
 
 .Edward E. Allen. 
 .Clarence E. Holmes. 
 
 J. J. Dow. 
 .R. S. Curry, M.D. 
 .S. M. Green. 
 .H. T. Menzemer. 
 .N. C. Abbott. 
 
 R. R. Pratt. 
 . Charles A. Hamilton. 
 .Edward M. Van Cleve. 
 .John E. Ray. 
 .B. P. Chappie. 
 .Chas. F. F. Campbell. 
 .0. W. Stewart. 
 .E. T. Moores. 
 .0. H. Burritt. 
 .T. S. McAloney. 
 .N. F. Walker. 
 
 .LeliaM. Curl. 
 .J. V. Armstrong. 
 .E. E. Bramlette. 
 .J. J. Donaldson. 
 
 .F. M. Driggs. 
 Helen G. Throckmorton. 
 W. A. Bowles. 
 Wm. C. Ritter. 
 Sadie E. Hall. 
 Parley De Berry. 
 J. T. Hooper. 
 
 Dept. for the Blind not yet 
 opened. 
 
state 
 
 Residential School 
 
 Place 
 
 THE Blind in the United States. — Corrected February, 1916. 
 ■olle 
 
 ""■ne enrolled Superintendent 
 
 1914-1915 
 
 »i u fTaUadeea (School for the Blind, J. S. Ganey, Resident Supt 1 
 
 ^'*'""°'' \TaUadega ^"^""^ '<>'■ Negro Deaf Mutes and Blind, J. S. Graves, ^08.. F. H. Manning. 
 
 [ Resident Supt. ) 
 
 Ar^.»'"«? Little Rock School for the Blind 156 . .John H. Hinemon. 
 
 Cahfomia Berkeley Institution for the Education of the Deaf and Dumb, and 94 L. E. MUlican 
 
 the Blind 
 
 Colorado Colorado Springs. SchooHor the Deaf and the Blind 37 W K Arso 
 
 Connecticut. . . .Hartford Institute for the Bhnd .' . 46.' .George H Marshall. 
 
 F'onda St. Augustine Institution for the Deaf and the Blmd 38 . . A. H. Walker. 
 
 Georgia Macon Academy for the Blind 113. .G. F. Oliphant. 
 
 Idaho Gooding State School for the Deaf and the Blind 18. .W. E. Taylor. 
 
 Illinois Jacksonville School for the Blind 210. .H. C. Montgomery. 
 
 Indiana Indianapolis Institute for the Education of the Bhnd 143 . . George S. Wilson. 
 
 Iowa Vinton College for the Blind 135. .George D. Eaton. 
 
 Kansas Kansas City Institution for the Education of the Blind 97 . . Isa A. Green. 
 
 Kentucky Louisville Institution tor the Education of the Blind 146. .Susan B. Merwin. 
 
 Louisiana Baton Rouge Institution for the Blind 60 . . G. C. Huckaby. 
 
 M 1 J /Overlea School for the Bhnd 1 „„ ,. „ „i j 
 
 '^"^'""'^ \Overlea School for the Colored Bhnd and Deaf Mutes / l^"' ■ J°'>'' ^- B''^'^«°«- 
 
 Massachusetts. .Watertown Perkins Institution and Massachusetts School for the Blind «90. .Edward E. Allen. 
 
 Michigan Lansing School for the Blind 173. Clarence E. Holmes. 
 
 Minnesota Faribault School for the Blind 123. .J. J. Dow. 
 
 Mississippi Jackson Institute for the Blind 78. .R. S. Curry, M.D. 
 
 Missouri St. Louis School for the Blind 115. .S. M. Green. 
 
 Montana Boulder .School for the Deaf and the Blind 18. .H. T. Menzemer. 
 
 Nebraska Nebraska City . . .Institute for the Blind 67. .N. C. Abbott. 
 
 New Mexico.. . . Alamogordo Institute for the Blind 46. .R. R. Pratt. 
 
 XT V 1, /Batavia State School for the Blind 190. .Charles A. Hamilton. 
 
 ^^"^ ^°^'^ \New York City. .Institute for the Education of the Blind 119. .Edward M. Van Cleve. 
 
 North Carolina . Raleigh Institution for the Deaf and Dumb, and the Blind 260 . . John E. Ray. 
 
 North DakoU. .Bathgate School for the Blind 26. .B. P. Chappie. 
 
 Ohio Columbus Institution for the Education of the iJlind 240. .Chas. F. F. Campbell. 
 
 Oklahoma Muskogee School for the Bhnd 91 . .0. W. Stewart. 
 
 Oregon Salem Institution for the Bhnd 38. .E. T. Moores. 
 
 „ , . /Philadelphia Institution for the Instruction of the Blind 230. .0. H. Burritt. 
 
 Pennsylvania. . ^Pittsburgh Western Pennsylvania Institution for the Blind 144 . .T. S. McAloney. 
 
 South Carolina . Cedar Spring Institution for the Education of the Deaf and Dumb, and 93 . . N. F. Walker. 
 
 South Dakota . . Gary School for the Blind 
 
 Tennessee Nashville School for the Blind 
 
 /Austin Institution for the Blind. 
 
 .Lelia M. Curl. 
 .J. V. Armstrong. 
 237. .E.E. Bramlette. 
 
 Texas \ Austin institution for the Deaf and Dumb and the Blind Colored 65 . . J. J. Donaldson. 
 
 Youth 
 
 Utah Ogden School for the Deaf and the Blind 34. .P. M. Driggs, 
 
 Vermont Brattleboro Austine School for the Blind 
 
 Virginia 
 
 Washington . . 
 West Virginia. 
 
 [Staunton 
 \Newport News, 
 
 .Vancouver 
 
 .Romney 
 
 .Janesvill 
 
 .School for the Deaf and t 
 
 Helen G. Throckmorto 
 W.A.Bowles. 
 
 Virginia State School for Colored Deaf and Blind 38. .Wm. C. Ritter. 
 
 State School for the Blind 64. .Sadie E. Hall. 
 
 School for the Deaf and the Blind 83 . . Parley De Berry. 
 
 136.. J. T. Hooper. 
 
 Wyoming.. .. '. '. ! Cheyenne Institution for the Blind and the Deaf and Dumb. 
 
 Total enrohnent, 1914-1915 4860 
 
 Dept. for the 1 
 opened. 
 
CHAPTER XX 
 
 THE POPULAR MOVEMENT FOR CONSERVATION 
 
 OF VISION 
 
 By Edward M. Van Cleve 
 
 managing director of the national committee for 
 
 the prevention of blindness 
 
 " Public health is purchasable; within natural limita- 
 tions a community can determine its own death rate." This 
 is the forceful declaration of the City and State Boards of 
 Health of New York. Its truth is being accepted and 
 proved more generally all the while. The corollary that 
 human powers can be conserved by taking thought is capa- 
 ble of demonstration in similar fashion. In the field of 
 conservation of vision this truth is accepted, that correct 
 knowledge of the means of avoiding harm to the eyes is 
 the surest road to saving sight, and the only purchase price 
 that is demanded is the effort made in securing that knowl- 
 edge. It is monstrous to think that any parent is willing 
 to let his child go blind if he knows the condition that will 
 inevitably bring on this calamity and knows the means of 
 prevention. For his child he will buy at any cost safety 
 from so great a calamity as losing sight. Enlightened 
 self-interest will lead the individual to care for his own eyes. 
 
 The movement for the conservation of vision is to-day 
 an educational movement concerning itself with bringing 
 to general attention the knowledge of specialists in saving 
 sight for the individual threatened or already in peril, that 
 society may be spared the increase of inefficiency through 
 the addition of handicapped men and women, and that the 
 public burden of providing for such handicapped persons 
 may be lessened. Conservation of vision is first a personal 
 interest; it becomes a social interest, even a public interest. 
 
 327 
 
328 HYGIENE OF THE EYE 
 
 Whoever learns that half of all blindness is preventable 
 experiences some sort of emotion. It may be only a mild 
 wonder why somebody does not do something about the 
 matter, or it may assume the opposite extreme of a burning 
 indignation or a divine pity inspiring action — vigorous, 
 persistent, effective. The discovery of Crede, in 1881, that 
 the instillation of a solution of a silver salt at the time of 
 birth in the eyes of the new-born babe will almost invariably 
 kill the germ which produces much blindness and impair- 
 ment of vision in babyhood, gave rise to widespread dis- 
 cussion by physicians and an effort to secure the general 
 use of the so-called Crede method. Success in reducing 
 to a minimum the cases of visual impairment, by this or a 
 similar method, wherever used, has given life to the en- 
 deavor of organizations and interested individuals to make 
 it a matter of universal knowledge that blindness from 
 inflammation in the eyes of the new-born is needless. To 
 accomplish this education of the public, recourse is had to 
 the newspaper, the popular magazine, the printed leaflet — 
 all the devices of advertising; also to the popular lecture 
 and the moving picture. 
 
 Other causes of blindness or reduced vision in childhood 
 claim attention. Ocular tuberculosis, interstitial keratitis, 
 eye troubles following measles and scarlet fever, synipa- 
 thetic ophthalmia, and progressive near-sightedness are 
 chief of these. Intelligence in handling these diseases comes 
 from spreading knowledge of their danger and directing 
 their victims to proper care. 
 
 Trachoma attacks both child and adult. It thrives in 
 Ignorance and neglect. Glaucoma in adults comes on in- 
 sidiously and the warnings of its approach are neglected 
 because unrecognized. In the industries, in the schools, in 
 the home, eye-strain is endured without consideration of its 
 
MOVEMENT FOR CONSERVATION OF VISION 329 
 
 calamitous effects. Yet all of these causes of visual im- 
 pairment may usually be avoided. It is the purpose of the 
 societies organized for the conservation of vision to bring 
 about universal knowledge of these facts. 
 
 The National Committee for the Prevention of Blind- 
 ness^ is engaged in this work of educating the public. It 
 serves as a clearing-house of information for all persons 
 interested in this effort to save sight. It prepares popular 
 literature and publishes it or furnishes the material for 
 articles to magazines, newspapers, and to individuals. It 
 has a large collection of lantern slides for use in illustrat- 
 ing lectures on the subject of conservation of vision. It 
 provides a lecture sei-^^ice by its own staff and lends assist- 
 ance to lecturers seeking help in preparing to present the 
 facts. It aids in the organization of societies and com- 
 mittees in states and cities, it advises in the passage of laws, 
 it provides expert service in every field for promotion of 
 this cause (see Figs. 117 and 118) . 
 
 The American JNIedical Association, through its Com- 
 mittee on Health and Public Education with a sub-com- 
 mittee on Conservation of Vision, secures publication of 
 pamphlets on many subjects concerning care of the eyes, 
 and provides for the press of the country a news service 
 which is widely used. This committee also promotes legis- 
 lation and maintains a lecture bureau for instruction of the 
 people, using the unpaid services of public-spirited mem- 
 bers of the medical profession. 
 
 Superintendents of schools for the blind, who are in a 
 position to know how much the blindness that is prevent- 
 able costs the individual and the State, have been active 
 in the task of spreading the knowledge of possible preven- 
 
 ^ This Committee has its office at 130 East 22d Street, New 
 York City. 
 
330 
 
 HYGIENE OF THE EYE 
 
 /*""""*" 
 
 
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 '^ a UJ O 
 
 
 45 S m 2? 
 •1 S ¥•? 
 
 ^2^1 
 
 EEYE 
 
 ous di 
 
 
 ^v*^ 
 
 s& 
 
 
 ^•,.»^<s 
 
 ^^ = J 
 
 ^H^te^^^^H 
 
 ^^^' 
 
 ic^f 
 
 ^^f - ^^^ 
 
 ca 
 
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 ^^^^ 
 
 
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 ^^Mw 
 
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 ^I^^PK^^^;i^ 
 
 I^E^g^ 
 
 ^HHHHHHHI 
 
 MBlBMMfr' . 
 
 O 
 
MOVEMENT FOR CONSERVATION OF VISION 331 
 
 tion. For years the publications of the schools for the 
 blind have included directions for prevention of needless 
 blindness. 
 
 Societies, committees, State commissions, and inter- 
 ested individuals have undertaken not only educational 
 work but remedial effort. An example of the sort of ser- 
 vice that may be rendered is shown in the admirable " fol- 
 low-up " work possible in Boston through the cooperation 
 of several organizations. Thus, a case is reported by an 
 agent of the Commission for the Blind or by doctor or 
 nurse to the Board of Health which sends a city nurse to 
 investigate. If necessary, the child (and sometimes the 
 mother with the child) is transferred to the Eye and Ear 
 Infirmary for treatment and care, and the hospital through 
 its social service department helps the mother and visits 
 the family after the child's discharge to see that the direc- 
 tions of the doctor are carried out. This kindly care is 
 kept up until the result aimed at is attained — a well child. 
 Such " follow-up " work is very important in cases of oph- 
 thalmia neonatorum, but it is also valuable in other kinds 
 of eye trouble, and the social service department is coming 
 to be considered an indispensable part of any well organ- 
 ized hospital, including general as well as special hospitals. 
 
 Such is the character of the work done in the movement 
 for conservation of vision. That success is attending the 
 efforts of the workers is evidenced by a gradual but steady 
 lessening of the number of children entering the schools for 
 the blind who have been rendered sightless through pre- 
 ventable causes. For many years, however, effort must be 
 continued and the scope of the work broadened until there 
 is wiped out the reproach on our civilization of allowing 
 any person to go through life with sight lost or seriously 
 impaired from preventable causes. 
 
INDEX 
 
 Accommodation, 17 
 
 power of, 18 
 Acromegaly, eye changes in, 231 
 Adenoids, cause of eye changes, 225 
 Albinism, 171 
 Albinos, choroid in, 7 
 
 iris of, 10 
 Alcohol, cause of color-blindness, 282 
 
 effect of, on eyes, 275 
 ethyl, 275 
 
 methyl or wood, 261 
 Alphabets for the blind, 304 
 
 American Braille system, 305, 306 
 
 Boston line type, 305 
 
 Braille system, 305 
 
 Hauy's system, 304 
 
 New York point type, 305 
 
 Philadelphia line type, 305 
 Amblyopia, alcoholic, 276 
 
 tobacco (see Blindness), 273 
 Ansemia, cause of eye changes, 206 
 Anisometropia, 45 
 Antimetropia, 45 
 Aqueous humor, 11 
 Artificial lighting, 101 
 
 contrasts to be avoided, 107 
 
 direction of, 108 
 
 fixtures, types of, 114 
 
 from architectural standpoint, 117 
 
 furniture and wall coverings of im- 
 portance, 115 
 
 illumination diffused, 106 
 directed, 106 
 
 light, quantity of, 116 
 
 sources, large and small, 106 
 
 lights, arrangement of, 101, 110 
 kinds of, 101 
 
 position of individual in relation to, 116 
 shades and reflectors, 103 
 
 Asthenopia, 61 
 
 muscular, 22 
 Astigmatism, 17, 42 
 
 compound, 17, 42, 45 
 
 correction of, 44 
 
 hypermetropic, 42 
 
 irregular, 42 
 
 mixed, 17 
 
 myopic, 42 
 
 regular, 42 
 
 simple, 17 
 
 symptoms of, 43 
 Atropine as a cycloplegic, 30 
 
 constitutional symptoms resulting 
 from, 31 
 
 glaucoma produced by, 32 
 
 in myopia, 39 
 
 objections to, 31 
 
 value of, 30 
 
 Bacillus, Koch-Weeks, 151 
 
 Morax-Axenfeld, 152 
 Basedow's disease, 226 
 Beverages, effect of, on eyes, 273 
 Blepharitis marginitis, 154 
 Blind, the, 283 
 
 children, education of, 287 
 
 nurseries for, 286 
 co-education with seeing pupils, 317 
 advantages of, 318 
 disadvantages of, 318 
 education of, 287 
 
 advanced courses, 319 
 American alphabets, 304 
 Boston line type, 305 
 Braille system, 305 
 Philadelphia line type, 305 
 drawing, 310 
 
 333 
 
334 
 
 INDEX 
 
 Blind, education of, embossed books 
 for finger readers, 320 
 history of, 287, 302 
 
 Hauy's raised characters, 302 
 literary department, 300 
 geography, 312 
 history, 312 
 languages, 310 
 mathematics, 310 
 reading, 302 
 -writing, 307 
 
 Hall Braille machine, 308 
 pencil, 308 
 provisions for, 286 
 sciences, 313 
 typewriting, 313 
 
 commercial work, 314 
 employment of, 321, 324 
 as instructors, 324 
 as literary writers, 326 
 as national and state ofiacials, 326 
 as piano-tuners, 324 
 industrial homes for, 323 
 literature for, 320 
 
 free transportation of, 321 
 monthly magazine, 321 
 music as a vocation of, 314 
 musical education of, 314 
 number of, in schools, 284 
 physical training of, 289, 291 
 athletic field, 294 
 bowling, 292 
 football, 296 
 gymnasium, 291 
 running races, 294 
 swimming pools, 292 
 schools for, 287 
 
 age of admission, 288 
 
 length of time in, 289 
 
 spot, Mariotte's, 21 
 
 training of the hand, 296 
 
 domestic science, 300 
 
 manual arts, 298 
 
 occupations, 300 
 
 Blindness, 283 
 alcoholic, 276 
 causes of, 283, 328 
 iodoform, use of, 278 
 obstruction of retinal artery, 174 
 ophthalmia neonatorum, 283 
 
 statistics, 284 
 poisoning, by lead, 263 
 
 methyl or wood alcohol, 261 
 quinine, 277 
 salicylic acid, 278 
 vascular disease, 174 
 vermifuges, 278 
 classification by age and sex, 285 
 color (see Color-blindness), 279 
 night, 175 
 
 partial, in tea and coffee drinkers, 27^ 
 prevention of, 328 
 
 Crede's method, 328 
 sudden total, in one eye, 175 
 ratio of cases to population, 285 
 relation of consanguinity to, 176 
 tobacco, 273 
 
 prevention of, 274 
 symptoms, 274 
 Blood diseases, cause of eye changes, 206 
 anaemia, 206 
 leukaemia, 207 
 Blood-vessels, disease of, cause of eye 
 changes, 208 
 of eyeball, 11 
 Brain tumor, eye changes in, 178 
 Bright's disease cause of eye changes, 20& 
 Burritt, on blindness, 283 
 
 Cancer of eyelids, 154 
 Car sickness, 65 
 Cataract, 171, 185 
 
 age in relation to, 185 
 
 of childhood, 186 
 
 congenital, 185 
 operation for, 191 
 
 cure of, 190 
 
 definition of, 185 
 
INDEX 
 
 335 
 
 Cataract, diagnosis of, 189 
 due to Bright's disease, 188 
 diabetes, 188, 212 
 excessive heat and light, 188 
 eye-strain, 188 
 iritis, 167 
 early symptoms of, 186 
 electric, 257 
 hereditary, 185 
 lamellar, 208 
 
 muscse, symptomatic of, 181 
 operation for, 190 
 
 delirium following, 230 
 prognosis, 193 
 technique, 191 
 time for, 194 
 progression of, 187 
 senile, 186 
 treatment of, 189 
 by absorption, 190 
 by dionine, 190 
 immature form, 189 
 incipient stage, 189 
 mature form, 189 
 zonular, 208 
 Catarrh, epidemic conjunctival, 151 
 Chalazion, 156 
 
 Chocolate drinking, effect of, on eyes, 27C 
 Chorea of eye-strain, 65 
 Choroid, 7 
 
 diseases of, 171 
 albinism, 171 
 coloboma, 171 
 inflammation, 172 
 malignant tumors of, 173 
 of albinos, 7 
 Choroiditis, 172 
 causes of, 172 
 
 tuberculosis, 172 
 diagnosis, 172 
 suppurative, 173 
 Ciliary body, 9 
 injuries of, 240 
 muscle, action of, in farsightedness, 27 
 
 Ciliary muscle, normal, 26 
 
 Coffee drinking, effect of, on eyes, 276 
 
 Coloboma, of choroid, 171 
 
 of iris, 167, 171 
 Color-blindness, 279 
 acquired, 280 
 
 cause of, 280 
 caused by alcohol and tobacco, 282 
 congenital, 280 
 hereditary, 280 
 history of, 279 
 Holmgren color test, 281 
 in relation to occupation, 280 
 lantern test for, 281 
 partial, 280 
 total, 280 
 Color field, 20 
 Conjunctiva, 5, 127 
 diseases of, 127 
 inflammation of, 127 
 soil for microorganisms, 127 
 Conjunctivitis, 127 
 acute catarrhal, 151 
 contagiousness of, 151 
 Koch- Weeks bacillus, 151 
 angular, 152 
 
 due to diseases of general system, 129 
 errors of refraction, 128 
 various microorganisms, 152 
 epidemic catarrhal, 128 
 follicular, 150 
 
 granular (see Trachoma), 142 
 metastatic gonorrhoeal, 141 
 treatment of, 141 
 women rarely affected by, 142 
 prevented by colored protecting glasses, 
 
 129 
 purulent, of adults, 139 
 course of, 140 
 
 due to gonorrhoeal infection, 139 
 treatment of, 140 
 to vaginitis, 142 
 of infants (see Ophthalmia Neona- 
 torum), 129 
 
336 
 
 INDEX 
 
 Conjunctivitis, subacute, 151 
 
 Morax-Axenfeld bacillus, 152 
 Cornea, 7 
 
 disease of (Keratitis), 162 
 
 eczema of, 162 
 
 foreign body on, 234 
 
 jagged tears of, 239 
 
 perforating injury of, 238 
 
 scratches of, 236 
 Crede's method for prevention of blind- 
 ness, 328 
 Cross-eye (see Squint), 28, 52 
 Cycloplegics, 30 
 
 atropine, 30 
 
 use of, in astigmatism, 45 
 in hypermetropia, 29 
 in myopia, 45 
 Crystalline lens, 9 
 
 hardening of, 46 
 
 removal of, in myopia, 41 
 
 Dalrymple sign, 227 
 
 Daylight illumination, from architec- 
 tural standpoint, 117, 119 
 factory buildings, 119 
 prismatic glass, 122 
 
 vault lights, 126 
 school buildings, 120 
 skylights, 125 
 Decompression operation, 179 
 Dental affections, eye changes in, 224 
 Diabetes, ocular changes due to, 210 
 
 cataract, 212 
 Digestive disturbances, due to eye-strain, 
 
 62 
 Double vision, 3, 22 ' 
 Drugs, effect of, on eyes, 273 
 injurious to vision, 277 
 iodoform, 278 
 quinine, 277 
 salicylic acid, 278 
 vermifuges, 278 
 
 Ear, diseases of, eye changes in, 225 
 Epilepsy, ocular phenomena of, 71 
 
 Eyes, blind, divergence of, 58 
 care of, 73 
 
 automobiling, 98, 99 
 in adults, 96 
 bathing, 98 
 moving pictures, 99 
 physical condition, 98 
 reading, 97 
 
 in recumbent posture, 97 
 veils, 97 
 changes in, due to disease, 205 
 adenoids, 225 
 acromegaly, 231 
 anaemia, 206 
 cardiac disease, 209 
 chlorosis, 206 
 deformities of skull, 230 
 dental affections, 224 
 diabetes, 210 
 exophthalmic goitre, 226 
 infantile paralysis, 232 
 infectious diseases, 212 
 cholera, 216 
 diphtheria, 214 
 erysipelas, 215 
 influenza, 215 
 leprosy, 216 
 malaria, 215 
 measles, 212 
 mumps, 216 
 scarlet fever, 213 
 small-pox, 214 
 tuberculosis, 216 
 typhoid fever, 215 
 whooping-cough, 216 
 leukaemia, 207 
 lightning stroke, 246 
 of blood-vessels, 208 
 of ear, 225 
 
 of kidneys (Bright's disease), 209 
 of nervous system, 227 
 hysteria, 229 
 insanity, 229 
 
 general paralysis of, 230 
 
INDEX 
 
 337 
 
 Eyes, changes in, due to disease of 
 nervous system, meningitis, 228 
 of respiratory tract, 224 
 of skin, 223 
 
 phthiriasis, 224 
 of spinal cord, 231 
 
 locomotor ataxia, 231 
 of sexual organs, 220 
 
 abnormal menstruation, 220 
 menopause, 220 
 pregnancy, 221 
 
 kidney disease of, 221 
 pernicious antemia, 207 
 poliomyelitis, anterior, 232 
 rhachitis (rickets), 208 
 venereal diseases, 218 
 gonorrhoea, 218 
 syphilis, 218 
 color of, 10 
 
 defects of, cause of car sickness, 65 
 vertigo, 64 
 correction of, economic value of, 84 
 influence of, on digestive system, 62 
 on general organism, 59 
 on nervous system, 59 
 eflFect on, of alcohol, 275 
 of drugs (see Drugs), 277 
 of school life, 33 
 of tobacco, 273 
 emmetropic, 16 
 examination of, before entering school 
 
 life, 75 
 far-sighted, 16 
 foreign bodies in, 233 
 
 removal of, 234 
 function of, 12 
 fundus of, ophthalmoscopic appearance 
 
 of, 25 
 hypermetropic, 16 
 in diseases of general system, 205 
 ophthalmoscopic examination of im- 
 portance, 205 
 involvement of, 205 
 infection of, 128 
 
 Eyes, interior of, diseases of, 171 
 length of, 16 
 myopic, 17 
 near-sighted, 17 
 of normal length, 16 
 ophthalmic picture of, 25 
 shape of, 6 
 structure of, 1 
 
 aqueous humor, 11 
 choroid, 7 
 ciliary body, 9 
 conjunctiva, 5 
 cornea, 7 
 crystalline lens, 9 
 external muscles, 3 
 eyelids, 3 
 iris, 10 
 
 lachrymal gland, 5 
 lashes, 4 
 orbit, 1 
 pupil, 11 
 retina, 7 
 sclerotic, 7 
 vitreous humor, 10 
 wounds and injuries of, 233 
 agricultural, 259 
 by blows from balls, 242 
 • burns, 236 
 
 chemical, 237, 261 
 in childbirth, 223 
 from golf ball explosions, 244 
 gun-shot, 241 
 household, 260 
 
 chemicals, 261 
 due to improper lighting, 263 
 industrial, 246 
 
 from blasting operations, 256 
 from breaking tools, 255 
 bums by molten metal, 247 
 from bursting gauges, 252 
 from electric flashes, 257 
 from emery wheels, 253 
 excessive heat and light rays, 256 
 
338 
 
 INDEX 
 
 Eyes, wounds and injuries of, indus- 
 trial, prevention of, 264 
 first aid service, 265 
 goggles, 267 
 warning placards, 266 
 statistics, 246 
 
 to bottlers of aerated waters, 258 
 to chippers, 251 
 perforation of globe, 238 
 from slingshots, 242 
 sympathetic inflammation, 240 
 Eyeball, blood-vessels of, 11 
 nerves of, 11 
 oscillations of, 70 
 and head jerking, 70 
 Eyeglasses and spectacles (see Spectacles), 
 
 26, 47 
 Eye-lashes, 4 
 
 displacement of, 157 
 Eyelids, 3 
 
 disease of, 154 
 
 blepharitis marginitis, 154 
 cancer, 154 
 chalazion, 156 
 growths, benign, 154 
 
 malignant, 154 
 herpes zoster, 158 
 hordeolum, 155 
 ptosis, 157 
 styes, 155 
 injuries of, 236 
 irregularities of contour, 157 
 movements of, 5 
 Eye muscles, paralysis of, head position 
 
 in, 66 
 Eye-strain, associated with epilepsy, 71 
 cause of bed wetting, 66 
 of cataract, 188 
 of chorea, 65 
 
 of contractions of facial muscles, 69 
 of faulty position of head, 66 
 of headache, 60 
 
 of spasmodic head movements, 66 
 of wry-neck, 70 
 
 Eye-strain, symptoms, absence of, in, 61 
 Exophthalmic goitre, 226 
 
 Factory buildings, daylight illmnination 
 
 of, 119 
 Farsightedness (see Hypermetropia), 26 
 Field of vision, 19 
 
 Floating bodies, in vitreous hmnor, 182 
 Foreign bodies, 233 
 on cornea, 234 
 removal of, 234 
 
 inflammation arising from, 235 
 treatment after, 235 
 in eye, 233 
 
 removal of, 234 
 Fortification spectrum, 183 
 Fovea centralis, ophthalmoscopic appear- 
 ance of, 25 
 Fundus of eye, ophthalmoscopic appear- 
 ance of, 25 
 Furber, on Daylight Illumination, 117 
 
 Gland, lachrymal, 5 
 Glaucoma, 171, 196 
 acute fulminating, 196 
 age in relation to, 204 
 chronic, 196 
 
 diagnosis, by ophthalmoscope, 198 
 
 by tonometer, 199 
 treatment of, by myotics, 203 
 operative, 203 
 definition of, 196 
 early recognition, 197 
 following iritis, 167 
 inflammatory, 170, 196 
 diagnosis, 199 
 operation for, 198 
 iridectomy, 202 
 trephining, 202 
 symptoms, 199 
 predisposing causes, 204 
 age, 204 
 heredity, 204 
 prevention of, 328 
 primary, 197 
 
INDEX 
 
 339 
 
 Glaucoma, produced by atropine, 32 
 prognosis of, 198 
 secondary, 197 
 subacute, 196 
 symptoms, 197 
 Glioma, 177 
 
 Goggles, value of, in preventing accidents, 
 267 
 color of glass, 272 
 statistics, 269 
 special forms of, 
 
 Pfund's lens for heat radiations, 271 
 for various occupations, 270 
 Gonorrhoea, 132 
 
 cause of purulent conjunctivitis in 
 adults, 139 
 in infants, 132 
 of iritis, 168 
 Graefe sign, 227 
 Graves' disease, 226 
 
 Head jerking and oscillations of eyeballs, 
 
 70 
 Headache, due to eye strain, 60 
 Heart, disease of, eye changes in, 209 
 Hemeralopia, 175 
 Hemianopsia, 21 
 
 significant of brain disease, 21 
 Herpes zoster, 158 
 Heterophoria, 22 
 Holmgren color test, 281 
 Hordeolum, 155 
 Hyperaemia, hypermetropic, 28 
 Hypermetropia, 26, 46 
 
 correction of, 29 
 
 optic principles involved, 29 
 
 hyperseraia of, 28 
 
 muscular activity in, 27 
 
 Illumination, diffused, 106 
 
 directed, 106 
 
 proper, effect of, on output of work, 126 
 
 of workshops, 263 
 Infantile paralysis, eye changes in, 232 
 
 Infectious diseases, ocular changes in, 212 
 cholera, 216 
 diphtheria, 214 
 erysipelas, 215 
 influenza, 215 
 leprosy, 216 
 malaria, 215 
 measles, 212 
 mumps, 216 
 scarlet fever, 213 
 small-pox, 214 
 tuberculosis, 216 
 typhoid fever, 215 
 whooping-cough, 216 
 Iridectomy, for glaucoma, 201 
 Iris, 10 
 
 of albinos, 10 
 diseases of, 167 
 
 iritis, 167 
 malformations, congenital, 167 
 
 coloboma, 167 
 perforating injury of, 239 
 Iritis, 167 
 
 causes of, 168 
 
 articular rheumatism, 168 
 gonorrhoea, 168 
 rheumatoid arthritis, 169 
 syphilis, 168 
 tuberculosis, 169 
 diagnosis of, 169 
 symptoms, 167 
 treatment, 169 
 Ives, on Artificial Lighting, 101 
 
 Keratitis, 162 
 interstitial, 164 
 causes of, 165 
 syphilitic, 165 
 prognosis of, 166 
 symptoms, 165 
 phlyctenular, 162 
 course of, 162 
 treatment, 163 
 tubercular, 217 
 
340 
 
 INDEX 
 
 Kidney disease, ocular changes due to, 209 
 
 of pregnancy, eye changes in, 221 
 Kryptok lens, 50 
 Koch- Weeks bacillus, 151 
 
 Lachrymal apparatus, diseases of, 159 
 congenital, 160 
 inflammation of sac, 160 
 lachrymation, 159 
 
 cause of, 160 
 treatment, 161 
 gland, 5 
 Lead poisoning, 263 
 Lens, perforating injury of, 239 
 Lenses, 14 
 Kryptok, 50 
 periscopic, 50 
 toric, 50 
 Leukaemia, eye changes in, 207 
 Lighting, artificial (see Artificial Light- 
 ing), 101 
 fixtures, 114 
 
 natural (see Daylight Illumination), 
 117, 119 
 Lightning stroke, effect of, on eyes, 246 
 Locomotor ataxia, eye changes in, 231 
 Loring's ophthalmoscope, 24 
 
 Macula lutea, 20 
 
 ophthalmoscopic appearance of, 25 
 Mariotte's blind spot, 21 
 Mastoid abscess, eye changes in, 226 
 Methyl or wood alcohol poisoning, 261 
 Migraine, due to eye-strain, 61 
 Miner's nystagmus, 71 
 Morax-Axenfeld bacillus, 152 
 Motes, 180 
 
 Moulthrop school chair, 77 
 Muscse, 180 
 
 volitantes, 37, 182 
 Muscle, ciliary, function of, 26 
 Muscles of eye, division of, in myopia, 41 
 
 external, 3 
 IMuscular asthenopia, 22 
 
 Mydriatics, 30 
 
 atropine, 30 
 Myopes, school life of (see School Life), 87 
 Myopia, 33, 46 
 
 age of arrest of progression, 33 
 of development, 33 
 
 atropine, value of, in, 39 
 
 causes of, 33 
 
 changes of vitreous in, 37 
 
 correction of, 39 
 importance of, 38 
 
 detachment of retina in, 37 
 
 diagnosis of, 36 
 
 division of eye muscles in, 41 
 
 frequency of examinations in, 40 
 
 glasses, constant use of, in, 40 
 
 hereditary influence, 33 
 
 motes of, 183 
 
 ophthalmoscopic examination for, 36 
 
 a pathological condition, -37 
 
 prevention of, 38 
 importance of, 38 
 
 progressive character of, 33 
 
 racial tendency, 32, 35 
 
 removal of crystalline lens in, 41 
 Myotics, 203 
 
 Near-sightedness, 32 
 Nerves of eyeball, 11 
 
 Nervous system, diseases of, eye changes 
 in, 227 
 hysteria, 229 
 insanity, 229 
 
 general paralysis of, 230 
 meningitis, 228 
 influence of optical defects on, 59 
 Nystagmus, 70, 226 
 hereditary, 70 
 miner's, 71 
 cure of, 71 
 
 Ocular muscles, 22 
 
 functional anomalies of, 22 
 vertigo, 64 
 
INDEX 
 
 341 
 
 ©phthalmia, gonorrhoeal, of adults, 139 
 of infants, 129 
 metastatic, 141 
 neonatorum, 129 
 
 blindness due to, 283 
 
 statistics, 284 
 cause of, 131 
 
 gonorrhoeal infection, 132 
 contagiousness, 131 
 course of, 130 
 innocent type, 132 
 onset of, 129 
 prognosis, 139 
 treatment of, 133 
 
 Department of Health instructions, 
 for child at birth, 137 
 when inflammation of eyes 
 
 appears, 138 
 during pregnancy, 136 
 silver nitrate, 133 
 stringent State laws, 134 
 Ophthalmoscope, 12, 23 
 Loring's, 24 
 
 method of illumination, 23 
 Optic foramen, 3 
 nerve, 25, 177 
 
 changes in, in brain tumor, 178 
 inflammation of, 178 
 neuritis, 177 
 
 in brain tumor, 178 
 cause of, 179 
 
 decompression operation, 179 
 diagnosis, 178 
 Optical defects, influence of, on general 
 
 system, 59 
 Orbit, 1 
 
 diseases of, 158 
 margins of, 3 
 shape of, 2 
 
 racial differences in, 2 
 walls of, 3 
 
 Perceptions, visual, 180 
 Perimeter, 21 
 
 Peripheral perception, 20 
 Periscopic lens, 50 
 Pfund's lens, 271 
 Phosphenes, 180 
 Physiology of vision, 12 
 Pinguecula, 153 
 Pink eye, 151 
 Poisoning, lead, 263 
 
 methyl or wood alcohol, 261 
 Poliomyelitis, anterior, eye changes in, 
 
 232 
 Power of accommodation, 18 
 Presbyopia, 46 
 
 correction of, 47 
 
 of old sight, 18 
 Princeton adjustable school desk and 
 
 chair, 78 
 Prismatic glass, 124 
 
 use of, in manufacturing buildings, 
 125 
 in school buildings, 122 
 
 vault lights, 126 
 Prisms, 15 
 
 Pseudopterygium, 153 
 Pterygium, 153 
 Ptosis, 157 
 
 congenital, 157 
 
 treatment, 157 
 Pupil, 10 
 
 size of, 11 
 
 Reading in recumbent posture, 97 
 Refraction, 16 
 anomalies of, 26 
 correction of, 26 
 anisometropia, 45 
 antimetropia, 45 
 astigmatism, 42 
 presbyopia, 46 
 far-sightedness, 26 
 hypermetropia, 26 
 myopia, 32 
 near-sightedness, 32 
 
342 
 
 INDEX 
 
 Hefraction, anomalies of, cause of con- 
 junctivitis, 128 
 of squint, 52 
 ophthalmoscopic measurement of, 25 
 Respiratory tract, diseases of, eye changes 
 
 in, 224 
 Retina, 7 
 
 detachment of, 176 
 
 treatment, 176 
 diseases of, 174 
 light-perceiving elements of, 7 
 pigmentary degeneration of, 175 
 tumors of, 177 
 gUoma, 177 
 Retinitis, 174 
 causes of, 174 
 syphilis, 175 
 of pregnancy, 221 
 Retinoscopy, 25 
 
 Rhachitis, eye changes due to, 208 
 Rheumatism, articular, cause of iritis, 168 
 
 School buildings, daylight illumination 
 of, 120 
 southern exposure preferable, 122 
 inspection, medical, 84 
 life, 73, 75 
 
 adequate lighting, 77 
 blackboards, 81 
 books, composition of, 82 
 size of type in, 83 
 examples of, 85 
 examination of eyes, 75 
 faulty postures, 80 
 length of lesson periods, 76 
 medical inspection, 84 
 
 economic value of, 84 
 of myopes, 87 
 classroom, 88 
 curriculum, 89 
 manual training, 90 
 for boys, 93 
 for girls, 93 
 physical training, 90 
 of partially sighted, 94 
 
 School life, proper seating, 77 
 
 special classes for pupils with defect- 
 ive sight, 86, 96 
 London methods, 87 
 style of writing, 82 
 rooms, lighting of, 118, 120 
 prismatic glass, 122 
 Sclerotic, 6 
 Scotoma, 21 
 Second sight, 41 
 Sexual organs, diseases of, eye changes in 
 
 (see Eyes, changes in), 220 
 Shadow test, 25 
 Sight, physiology of, 12 
 Sign, Dalrymple, 227 
 
 Graefe, 227 
 Skin diseases, eye changes in, 223 
 Skull, deformities of, cause of eye 
 
 changes 230 
 Skylights, 125 
 
 artificial, 125 
 Snow blindness, 245 
 Sparks, 180 
 
 Spectacles and eye-glasses, 26, 47 
 adjustment of, 48, 51 
 
 for near use, 50 
 bifocal, 48 
 choice of, 48 
 
 colored or tinted lenses, 31 
 "fronts," 50 
 Kryptok lens, 50 
 periscopic lens, 50 
 toric lens, 50 
 size of, 50 
 Spinal cord, diseases of, ocular changes 
 in, 231 
 curvatures, due to school seating, 80 
 Squint, 52 
 causes of, 52 
 congenital, 52, 56 
 correction of, 57 
 operative treatment, 57 
 advancement, 57 
 tenotomy, 57 
 
INDEX 
 
 343 
 
 Squint, convergent, 54 
 correction of, 54 
 
 divergent, 56 
 
 due to errors of refraction, 52 
 
 paralytic, 52 
 St. Vitus' dance, due to eye-strain, 65 
 Strabismus (see Squiut), 28, 52 
 Styes, 155 
 
 abortion of, 155 
 
 treatment, 155 
 Syphilis, 218 
 
 acquired, 219 
 
 cause of interstitial keratitis, 165 
 of iritis, 168 
 
 hereditary, 219 
 
 Tea drinking, effect of, on eyes, 276 
 Tear sac, 6 
 Test shadow. 25 
 
 Holmgren color, 281 
 lantern, 281 
 Tobacco, cause of color-blindness, 282 
 blindness, 273 
 
 prevention of, 274 
 symptoms, 274 
 Toric lens, 50 
 Trachoma, 142 
 acute stage, 142 
 among school children, 147, 148 
 contagiousness, 145 
 control of, in adults, 148 
 
 •among school children, 148 
 course, 142 
 curability, 144 
 detection of, 150 
 a disease of poverty, 146 
 eyelids in, 157 
 history of, 145 
 prevention of, 148, 328 
 
 rules for, 149 
 regions of its occurrence, 146 
 Trephining for glaucoma, 202 
 Tuberculosis a cause of iritis, 169 
 
 Tumor, of brain, optic neuritis in, 178 
 of choroid, 173 
 of retiua, 177 
 
 Van Cleve, on Conservation of Vision, 327 
 Veils, weariug of, 97 
 Venereal diseases, eye changes in, 218 
 gonorrhoea, 218 
 syphiHs, 218 
 Vertigo, 64 
 ocular, 64 
 
 treatment of, 65 
 Vision, binocular, 21 
 conservation of, 327 
 
 Boston "follow up" system, 331 
 causes of blindness, 328 
 education of public by American 
 Medical Association, 329 
 by National Committee for Pre- 
 vention of Blindness, 329 
 by superintendents of schools, 
 329 
 prevention of bhndness, 328 
 Crede method, 328 
 direct, 19 
 double, 3, 22 
 field of, 18 
 defects in, 21 
 hemianopsia, 21 
 scotoma, 21 
 small blind areas, 21 
 for color, 20 
 indirect, 20 
 physiology of, 12 
 accommodation, 17 
 lenses, 14 
 ocular muscles, 22 
 prisms, 15 
 visual acuity, 18 
 field, 19 
 Visual acuity, 18 
 perceptions, 180 
 
 fortification spectrum, 183 
 motes, 180 
 
344 
 
 INDEX 
 
 Visual perceptions, muscse, expression of 
 disease, 181 
 physiological, 180 
 
 muscse volitantes, 182 
 
 of epilepsy, 183 
 
 of insanity, 183 
 
 of migraine, 184 
 
 phosphenes, 180 
 
 sparks, 180 
 Vitreous humor, 10 
 
 diseases of, 170 
 
 floating bodies in, 182 
 
 penetrating wounds of, 240 
 
 Wall-eyed, 56 
 
 Wetting of bed, due to eye-strain, 66 
 White of the eye, 7 
 Wild hairs, 4, 157 
 Window of the eye, 7 
 Wounds and injuries of eyes, 233 
 agricultural, 259 
 of cornea, 234 
 due to blows by balls, 242 
 golf ball explosions, 244 
 gmishot, 241 
 improper lighting, 263 
 
 Wounds and injuries of eyes, slingshot, 242 
 household, 260 
 
 chemicals, 261 
 industrial, 246 
 
 from blasting operations, 256 
 from breaking tools, 255 
 from bursting gauge, 252 
 from electric flashes, 257 
 from emery wheels, 253 
 from molten metal, 247 
 to bottlers of aerated waters, 258 
 to chippers, 251 
 prevention of, 264 
 first aid service, 265 
 goggles, 267 
 statistics, 246 
 warning placards, 266 
 of lids, 236 
 
 perforation of ciliary body, 240 
 of globe, 238 
 of iris, 239 
 of lens, 239 
 of vitreous, 240 
 
 sympathetic inflammation, 240 
 Wry-neck, due to paralysis of ocular 
 muscles, 70 
 
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