THE RECENT introduction of my preset lens into the United States by lectures of Lindner,1 as well as the fact that this lens is now being manufactured in the United States under the name the "Hruby diagnostic lens" gives me an opportunity of publishing a short paper on my technic of examination.
Only thirty years have passed since the slit lamp was used for the first time for examination of the posterior section of the eyeball through the efforts of Koeppe.2 He was the first to recognize that the deeper parts of the eye can be made visible only if, in general, two conditions are complied with. These are, on the one hand, the smallest possible angle between the optical axis of observation and that of illumination, and, on the other, such an intense dispersion of the rays coming from the depth of the eye and leaving it