This divider caliper was used to measure lengths accurately whether that was for engineers or navigators. It shows us the world before digital technology was introduced. People who used maps used to ...

Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at www ...

Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at www ...