Opisometer

An opisometer is a tool used for measuring distances on a map. It's like a little wheel with a handle that you can roll along the lines on a map to figure out how far you need to go. Say you want to know how far it is from your house to the park. You can use an opisometer to measure the distance between your house and the park on a map. You just roll the little wheel along the line that represents your route and the opisometer will show you how far you need to travel. It's a very helpful tool for people who need to plan routes or figure out how far they'll have to travel to get from one place to another.