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Fine regulation:
Exact adjustment of period of the pendulum by adding small weights on the fine regulation table. Adding weights speeds up the clock. Removing weights slows it down.

Fourth Wheel:
Part of the gear train between the minute wheel and the escapement wheel.

Free Strasser escapement:
The escapement in the clock, consisting of the pallet assembly and escapewheel, is the connecting link between the gear train and the pendulum. The escapement must supply the pendulum with the energy lost due to internal friction in the suspension spring and in moving through the air. Before the free Strasser escapement was invented for pendulum clocks, it was the so-called Graham escapement which served as the connecting link between the pendulum and the gear train. In the case of this escapement the anchor and the pendulum form a rather rigid connection through the pallet fork, the disadvantage being that even the slightest variations in the driving force are transmitted from the gear train to the pendulum. These variations in force result in a change of the amplitude of oscillation of the pendulum and thus influence the time of oscillation to a small extent. By the invention of the »free Strasser escapement« it was now possible to improve the already excellent accuracy of the precision clocks once more. This is primarily achieved by de-coupling the clockwork from the pendulum to a large extent. The pendulum is linked to the pallet arbor just by the two thin strips of spring steel of the suspension spring. In order to supply the pendulum with the energy necessary for maintaining the oscillation, the two pendulum driving springs are twisted by an angle precisely defined angle by the geometry of the escapement. The pendulum is thus supplied with the same power every swing, every second. The escapements in our Secunda Accurata 1958 and 1968 can therefore be described as »constant force« escapements.

Friction:
When designing a movement, avoiding friction is a main goal. Therefore all gear train bearings are equipped with ball bearings. Sometimes friction is necessary, for example, at a friction spring acts as a slipping clutch in the motion work, to make setting hands possible.

Friction bearing:
Bearing where the pivot turns in a drilled hole. Since materials glide on each other, it is necessary to choose different materials and lubricate.