A new geophysical technique for the remote measurement of the electromagnetic properties of natural surfaces was investigated. Theoretical and laboratory work has produced evidence for the validity of the use of ultra-high frequency radio reflection spectrometry for remote sensing of salinity of brackish water. A preliminary study of the electromagnetic properties of aqueous sodium chloride, computer-generated frequency dispersion curves of the dielectric coefficients, power reflectance, brightness temperature, and skin depth of water as a function of eight different normalities of sodium chloride, corresponding to a salinity range from pure to ocean water and as a function of five different temperatures from 0C to 40C to the radio frequency range from 10 to the 6th to 3 x 10 to the 10th power Hertz were constructed. A laboratory prototype radio reflection spectrometer was designed and assembled from commercially available swept-frequency UHF-microwave test equipment, a single horn antenna, and a hand-made coaxial sample cell. (Modified author abstract)