Definition
Whole degrees are read where the index arm marker falls on the arc. The micrometer drum, geared to the arm, reads minutes of arc from 0 to 60, and a vernier scale alongside it subdivides to 0.2 or 0.1 minutes. Older instruments use a vernier directly against the arc without a drum. A reading of 42 degrees on the arc, 17 on the drum and 4 on the vernier is recorded as 42 degrees 17.4 minutes.
Want to apply this on the water?
Ask Saily out loud for an example, a scenario or a simpler explanation.
Talk to Saily