The purpose of this study was to discover whether blood plasma has any "gluing" effect when placed between the neuro-epithelial and the pigment layer of an experimentally detached retina, as claimed by Strampelli.1The method first employed to obtain detachment was a simple one, in which a spatula was used to separate the neuro-epithelial layer under observation through a hand ophthalmoscope. The difficulty of working on the fundus while watching the spatula through the ophthalmoscope, as well as the gossamer fragility of the tissue involved, made this method impracticable. The final technic, and one which proved to be easy and satisfactory, was to bleb off the neuro-epithelial layer with physiologic solution of sodium chloride under direct observation through a hydrophthalmoscope.2The hydrophthalmoscope developed for working on the fundus consists of a brass chamber,A, with a small plano observation glass,B, set at an angle of