The Seagull ST19 is a manual-wound column-wheel chronograph that is a slightly modified version of the Venus 175. Seagull bought the patent and machinery from Venus in the early 1960s and has produced the ST19 since 1963. The ST19 has 2 more jewels than the Venus 175.
Despite its long history, I have classified this movement under the modern category as it is still being produced.
Full movement
Focus on the balance wheel
Balance wheel removed
Focus on the springs
Intermediate driving wheel spring
Operating lever spring
Focus on the column-wheel mechanism
Intermediate driving wheel removed
Focus on the zero resetting mechanism
Operating lever
Operating lever removed
Hammer
Seconds and minute wheels bridge
Bridge removed
Focus on the seconds and minute wheels
The seconds wheel with its heart cam allowing for the zero reset and its finger that advances the intermediate minute wheel once every minute
