There were several models of these, some were numbered and one, which I have, was called the "Abbey." It is not the same as the later New Haven "Abbey" model that is much more common. Willcock's patent for the gongs was August 28, 1894, and Gunther's patent for the resonator was March 27, 1896. The clocks appear in New Haven catalogs in 1900 and 1911. Chime Clock No. 1 is dated 1895, but I believe that has a single movement. My clock does not have the iron mounting bracket for the movements. It could be missing, though there is no evidence it was ever there. The Abbey case style looks a little older to me than the numbered models. My guess is that these clocks with the Willcock patent were made from the late 1890s to not much past 1911.