Copper sulfate method for measuring specific gravities of whole blood and plasma, with line charts for calculating plasma proteins, hemoglobin, and hematocrit from plasma and whole blood gravities [with list of references]; by Robert A. Phillips, Donald D. Van Slyke, Vincent P. Dole, Kendall Emerson, jr., Paul B. Hamilton, and Reginald M. Archibald, with technical assistance of Emily G. Stanley and John Plazin.