ive seen civics with 2 clutch cylinders, whats the purpose of that?

 

um like the slave & and the master?

the master cylinder holds clutch (brake fluid dot 3) and when you push on the clutch pedal it pushes through the clutch lines to the slave cylinder which i used to engage/disengage the clutch. its a simple hydraulic system and works much like a hydraulic brake set up.

hope this helps.