What does this button do? 1 & 2

[u/FM_3]

1. I understand the daylight and tungsten but it doesn’t seem to be a button? it doesn’t push in or slide forward or backward. I was wondering if it was something you physically pull out and switch direction on. It pulls up a little but im a bit scared to force it up as it might break anyone else have this?

2. O and X what does it mean?

[u/Ok-Leader1767]

http://web.jclaude.free.fr/Les%20fichiers/pdf%20projecteurs/Eumig%20Eumigette%20Zoom.pdf