1913 and 1918 catalogues; popular model. ‘Panthenon’ is not a separate model: it was a spelling misprint on an early label run (per Jim Connell, Charlton Standard Catalogue of Canadian Clocks); the wrong labels were used up, then corrected, so early examples exist with either spelling. A hybrid example is recorded: a Pantheon case with round columns but a ‘Pantheon B’ label (the Pantheon B normally has flat columns), with tuned rods.