The technique of smal1-angle soattering (SAS) is now about sixty years o1d. Soon after the first observations of, a continuous, intense X-ray scattering near the primary beam from samp1es such as canbo: tt, bla: cks, it was recognized that this scattering arose from e1ectron density heterogeneities on a scale of severa tens to severa hundred times the wave1ength of the radiation used. By the time the classic monograph of Guinier and Foumet appeared in 1955, much of the basic theory and instrumentation had been developed, and applications to colloidal suspensions, macromolecular solutions...