I'm trying to create a small compilation of maps that may have been collected or made by an adventurer or pirate as a story hook for a new campaign. I love researching new things so I've been reading about the history on maritime mapmaking and such to find how the compass rose came to be and the purpose behind rhumb lines. The questions To which I cannot seem to find answers are:

1) how are they used practically by sailors to predict travel time and distance?

2) how was the location of the compass rose determined on a given map?