1996 merc 150 xl cooling ( ?) system help

[bestcoast]

Just bought it and im going over a few things , this pipe must be attached to something right ? having a heck of a time finding any info on it
https://drive.google.com/file/d/0B0dKFjXK33FROHpNWm8tMUptT0V1S04zRE9jU1p6SjdjaXNJ/view?usp=sharing

 

[Faztbullet]

That the speedo tube...