An American drop dial Calendar Clock dating from c.1890, by the William L. Gilbert Clock Company, Winsted, Connecticut.
The clock has a really interesting dial system – the calendar movement was patented by Galusha Maranville on March 5th 1861, and manufactured by the W. L. Gilbert & Co. until 1866. In 1885, Gilbert modified the design such that the date could be advanced at the end of each month using a pin or pencil, instead of the key. This clock is one of these later examples, which was produced for about 18 years. This Office Drop Calendar clock is illustrated and discussed by Tran Day Ly in his book Calendar Clocks.
Housed in an attractive walnut case, the crest has fancy scroll carvings, and leaf, rosette and cornucopia carving below, and a sea shell carving to the base.
The 15-inch dial comprises three paper-covered metal discs;
a front disc which is fixed, contains the chapter ring with black Roman hour numerals and an outer ring with the 31 date calendar signed Wm. L. Gilbert Clock Co. Winsted, Ct., and has cutouts for the second disc;
a middle disc contains the sequential days of the week with Sunday highlighted in red and finally a cutout at the top exposing the months;
a third disc has the months.
The red date indicator moves automatically while the clock is running and the rear dials are manually adjusted at the end of each month. This is easily done by inserting a pencil (or similar) into holes which border the two rear discs. These holes are visible through the top rectangular cutout.
The 8-day clock movement strikes the hours on a coiled gong.
The wood rod pendulum with polished brass bob is visible through the reverse-painted lower door glass.