LVI. <i>A</i> table <i>of the beats, on Mr.</i> William Hawkes's <i>patent organs and piano-fortes, calculated by the Rev.</i> C. J. S<scp>myth</scp>; <i>and communicated, with some remarks, by Mr.</i> J<scp>ohn</scp> F<scp>arey</scp>