A ship's rudder indicator is used for measuring the angle of slope or pitch of the vessel. The information can be used to adjust the steering of the ship to give safe navigation. The rudder indicator transmitter once contained in this box was battery operated, according to the label inside this box. Box, wooden, used to store a battery operated Siemen's ship's rudder indicator. Made in the United Kingdom. Descriptive leaflet glued inside hinged lid. Lid secured by hooked catch. Brass latch. Metal mounting plate. Hole drilled in back. Dovetail joints. flagstaff hill, warrnambool, shipwrecked-coast, flagstaff-hill, flagstaff-hill-maritime-museum, maritime-museum, shipwreck-coast, flagstaff-hill-maritime-village, siemen's brothers london, siemen's rudder indicator box, nautical instrument for measuring pitch or slope, scientific instrument box, navigational instrument box