 communicate in the face of powerful enemy interference, a challenge officially recognized as one of the most impor- tant matters connected with the war" [78, footnote 48]. From the First World War on into World War II, the furtherance of wide- band techniques continued at the Hammond Laboratory, with concentra- tion on frequency-wobbling methods to send secret signals which sounded like " some new kind of man-made static " [78,p.1203]. The anti-jam- ming attribute of spectrum spreading became obvious as the frequency devi- ation of the wobbling increased SO that its " wider swing reduced the amount of time that a given narrow-band disturbance could affect the inter- mediate-frequency circuit of the receiver " [78, p. 1202]. Contributions of this kind, originating in that era from the Hammond group (additionally to [66]), are documented in patents on TR and SR wobbling which were filed, respectively, by Emory L. Chaffee [79] in 1922 and Ellison S. Purington [39] in 1930. The Chaffee patent claims that his invention, involving "rapid and erratic" wobbling, is useful for "secret radio telephony" and for " telegraphic sig- nals or radio-dynamic control." With respect to the Purington patent [39] (which seems somehow to have been overlooked in the chronicles [78] and [80]), that SR invention for obtaining "secrecy in which a rapid variation rate is necessary for the wobbling was a sequel to Hammond/Navy exper- iments of 1921-1922 which established points of interest regarding information theory when the interference greatly exceeds the signal" [78, p. 1202]. Also, circa 1920, the Hammond company had contracts from the U.S. Army to show that "noninterferable characteristics" could be secured for the radio control of aircraft [80, p. 1262]. During World War II, the NDRC entered the realm of guided missiles with a variety of projects [81] including the radio control in azimuth only (AZON) of conventionally dropped bombs (VB's) which trailed flares for visibility, radar-controlled glide bombs (GB's) such as the Pelican a