This volume contains articles on the history of ophthalmology.

The 1973 - postgraduate courses in ophthalmology held under the auspices of the Netherlands Ophthalmological Society, mark the 25th anniversary of the rebuilt Rotterdam Eye Clinic. The themes set for these courses: 'Ophthalmic Photography', 'Electro- ophthalmology' and 'Echo-ophthalmology', have been chosen from a multitude of rapid developments in ophthalmology during this period. The aim was to provide the clinician with a lead in a bewildering field of apparatus and techniques and to help him in selecting methods that provide useful results without too much specialised knowledge. However,...

When the eyeball is indented in total darkness, within less than 200 mil liseconds an oval or quarter-moon shaped spot of light is perceived in the part of the visual field corresponding to the indented region of the retina. In the seconds following, this phosphene extends across the whole visual field and alters in structure during further eyeball indentation. It is then seen as irregular large bright spots of light, finely structured moving light grains ('light nebula') and stationary bright stars. Regular geometrical patterns appear only when both eyes are indented simultaneously 1]. When...