抄録
For any type of compass card available aboard it must of course be guaranteed the circumstance that the geo-magnetic field in which the ship is situated is virtually negligible. Moreover, the drag of angular restoration the card inevitably shows as the ship turns is also desired to be as small as possible. Though this angle may be minimized by reducing the viscosity of the liquid filling the compass bowl, the card will also be made fidgety thereby showing an enlarged deflection peak and shortened period of swing. In order to solve this dilemma a few types of filament damper were examined of the efficacy of their application. The present paper deals with the effect of such dampers reflected on the behavior of a compass operated in distilled water as a model liquid of low viscosity. The test was carried out for various values of viscosity (0.71-1.31×10^<-2>cm^2/sec) realized by changing the temperature of the distilled water. The result of the test indicates that if the value of d 0.31 of the dampers is about 50 the damping character would be best one in this compass liquid which has above mentioned range of kinematic coefficient.
