3. Repeaters—operated from the Master Compass, and indicating its
exact reading at any instant.
4. Motor-generator—for converting the ship’s current into current of
proper characteristics for spinning the gyro wheels and operating the
repeaters.
5. Storage Battery—for emergency operation of the equipment in case of
failure of the ship’s supply.
The function of each piece of equipment and its relation to other parts
is shown on pages 22 and 23.