Description
Brass Maritime Three-Range Ship Clinometer
Item Overview
This brass maritime clinometer is a shipboard instrument used to measure a vessel’s angle of heel. It features three curved, liquid-filled glass tubes mounted to a graduated brass panel and set within a wooden display frame. Its wide measuring range made this style useful aboard naval, commercial, and support vessels.
Identification and Features
The upper scale reads from 0 to 20 degrees on either side of center. The middle scale reads from 0 to 45 degrees, while the lower scale reaches 60 degrees in both directions. The different ranges let a crew observe small changes as well as severe angles. Brass clips and screws secure the tubes to the panel. The rear has fiberboard backing and two sawtooth wall hangers. No maker name, serial number, military ownership mark, or date is visible in the supplied photographs.
How It Works
Each curved tube contains fluid and an air bubble. When the vessel remains level, the bubble rests near zero. As the ship heels to one side, gravity moves the bubble along the matching degree scale. The sensitive 20-degree tube shows small changes clearly, while the 45- and 60-degree tubes continue measuring during heavier rolling or a serious list.
Documented Shipboard Application
This arrangement closely matches the U.S. ship clinometer board pattern listed under MIL-C-20061 and NSN 6605-00-391-4234. That pattern used a brass board with 20-, 45-, and 60-degree bubble-tube scales. However, the absence of a data plate means this example cannot be confirmed as a U.S. Navy contract item. It should be identified as a maritime clinometer of the military-specification pattern.
Instrument History
Mariners have long used clinometers to measure roll, pitch, heel, and list. Bubble-tube versions offered simple operation without electricity or complex moving parts. The U.S. military standardized this general design through MIL-C-20061 during the twentieth century. A later commercial item description, A-A-59308, continued to cover bubble-in-tube ship clinometers used for measuring heel and trim.
Shipboard Stability and Damage-Control History
A clinometer helped officers judge how cargo loading, fuel use, sharp turns, wind, flooding, or battle damage affected a ship. A lasting reading to one side warned of a permanent list, while repeated movement showed the ship’s roll. Damage-control teams could compare readings while pumping compartments, shifting weight, counter-flooding, or conducting salvage work.
History of Naval Use
This instrument is not part of one specific weapons system. On a warship, it belonged to the larger stability, navigation, and damage-control system that helped keep the vessel and its weapons operating safely. Wartime records describe clinometers being used to report lists aboard damaged ships. Clinometers and trim indicators were also used during the difficult work of righting and refloating the capsized battleship USS Oklahoma after the attack on Pearl Harbor.
Condition
This used clinometer shows age-related patina, oxidation, spotting, scratches, finish wear, and handling marks across the brass panel and hardware. The three glass tubes appear intact, retain colored fluid, and show visible bubbles. The wooden frame and rear backing display wear consistent with storage and display. Calibration is not certified. This instrument is non-ordnance and contains no explosive components. All ordnance is inert.
Ideal For
This multi-range ship clinometer is well suited for maritime collections, naval displays, warship restorations, museums, nautical décor, educational exhibits, and collectors of historic shipboard instruments.
Approx length 20", Approx width 14", Approx height 1.5", Approx weight 8.2lbs.
Pictures are stock images of our inventory. Unless otherwise noted, you will not be receiving the exact item shown in the pictures. The pictures are representative of the item’s general condition. The item you receive might be slightly better, or worse, condition than was shown in the pictures.
Please visit our page about order lead times here: Order Lead Times.