No ordinary milling machine, here is a special one, by the high-class watchmaker Breguet Frères & Cie,  dedicated to milling out the cases of pocket watches. The case body was first machined as a ring with the correct inside and outside diameters and shape - this being work being done on an ordinary lathe using form tools or on a special pantograph lathe called "Dubail". Once turned to shape, the ring was then ready for milling and was secured over a collet that expanded over a holder that could be slid along the front of the machine. By turning a handwheel at the right-hand end of the machine, an operator could move the job to pass, in turn, beneath the various spindles and their cutters. Unfortunately, on the machine below, the table is not original and the essential case-holding block is missing. The two spindles at the right-hand end cut the special-shaped grove on the underside of the ring for the hinge mounting on its front face, while the next three spindles did the same work for the cover on the back face -  high-quality pocket watches had covers on both faces and, sometimes, even a third 'glass ring' cover beneath the cover on the back face. When all the groves had been cut, two holes were drilled in the opposite side of the ring for the pendant - and more if they were needed for special knobs, etc. The position of the holes was managed using a hand-lever and an index plate, an upper lever bringing the drilling spindle forwards. Finally, the case body was ready for soldering with little tubes let in the form hinges and the pendant held in position by two pins.
The function of the last of the milling spindles, the one that can be swivelled on its horizontal axis, is unknown. One poor photograph below shows such a machine in use in a Geneva factory in 1908. Once set up and adjusted, it may be presumed that an unskilled worker could have operated the machine with little difficulty.