A new method of viscosity measurement of dilute aqueous biological solutions employing a vertically oscillating spherical buoy is combined with an earlier magnetic densimeter method. It shows promise of rapid, truly independent and simultaneous measurement of the two quantities. A prototype instrument, accurate in viscosity to 2 or 3 x 10 to the -3 will be redesigned and further developed in the proposed research. The main thrust will be: a) improved stability and precision to 2 or 3 x 10 to the -4 in viscosity while retaining 10 to the -6 precision in density, b) use of commonly available commercial instruments almost entirely so that the device can be easily duplicated elsewhere, c) use of the instrument with a wide range of solutions to give confidence in its range of applicability, to develop an ease with measurement technique and tiny corrections, if any, and d) finally to install less proven but specially sensitive, low-noise sensors so the instrument can be used for small amplitudes, less than 100 angstroms, in a search for new effects when translatory motion is comparable to molecular dimensions.
