An early 20th-century Belgian mechanical pigeon-racing clock and recorder, or “constateur”, provisionally dated circa 1920–1930. The glass bears the inscription Plasschaert Frères, Wachtebeke, Belgique, while the dial is marked “Constateur A. Plasschaert – Breveté S.G.D.G.” Housed in a wooden carrying case with a leather carrying handle, the apparatus incorporates a brass rotating carousel with positions numbered 1–20, a paper-printing mechanism and a clock dial visible through a circular glazed aperture in the underside, with separate indications for hours, minutes and seconds. These instruments were designed to register the arrival of racing pigeons by securing their removable race rings in successive compartments and recording arrival times on paper. Original French and Dutch operating instructions survive inside the lid, and the case carries the stencilled number 2887. The wood retains its attractive aged colour and surface wear; the metalwork shows tarnishing and oxidation, the dial has spotting and discolouration, and the leather carrying handle shows substantial cracking and wear. One of the handles is detached. The apparatus is mechanically complete but untested, and no guarantee of working order is given. A wonderful display object, combining intricate mechanical engineering with the character and history of Belgian pigeon racing. Please examine all photographs carefully as part of the description.