Electrophoretic determination of protein values in normal aqueous humor offers considerable difficulties, owing to the following two factors: Proteins are present only in minute quantities, whereas there are considerable quantities of salts as against the low protein concentration. I. The Minute Protein Quantities The aqueous humor normally contains 10 to 40 mg. of total protein per 100 ml., i. e., 10μg. to 40μg/100μ1. (microliters), according to Amsler, Verrey, and Huber (1955). Paper electrophoretic examination of blood serum under favorable conditions generally requires 10μ1. (600 to 800μg. of protein). Quantities of less than 5μ1. yield no reliable results, as shown by the investigations of Klatskin, Reinmuth, and Barnes (1956), who made a critical analysis of quantitative-fractional paper electrophoresis of blood proteins, and by our personal observations. If the protein solution is deposited on the paper at one localized point rather than in a line, then the serum quantity required can be