This paper describes the construction of and behavior of a large spherical transducer formed as a mosaic of ceramic elements with no inactive material Formulas are shown that describe the several elements which form the building block of the assembly. The developed techniques indicate spheres up to 30 in. in diameter can be easily constructed and a modification of the basic element will permit much larger spheres to be built. Complete evaluation of a 10-in.-diam sphere is shown with efficiencies approaching 100%. Correlation between its evaluation and the theoretical report of S. Hanish at NRL is shown. Behavior in water indicates a good acoustic loading and wide-band operation.