II. AN important objection was made to me some years ago by Capt. Evans against the use of quadrantal correctors in the Navy, that they would prevent the taking of bearings by the prismatic azimuth ...

THE subject of this lecture is the gyrostatic compass, often called the gyro-compass. An engineer of my acquaintance was asked if he under-stood what a gyro-compass was, and he replied, “Of course I ...