Use and value of there please?

These came with my boat when I bought her but I just found them again and am not sure of their use or value?
The Brunton is a compass but not sure what kind or the use of the extra adjustments underneath and the spirit levels?
And the other is maybe some kind of wind gauge but again how to use on a sailboat?













Any info would be good and are they worth anything? They are both in good condition, no scratches and both come with cases, the Brunton in a very thick leather case.

thanks

Hey mate I thought I recognised the compass- so looked it up - there is a lot of info online about "brunton" brand. Also some on wikipedia, sorry I couldn't post a link. They are good quality.