NavList:

Using an artificial horizon in harbor from a floating dock is best done with a shielded tray of water* so that the slight dock motions are quickly compensated for. A thin tray with a thin scrub pad in the bottom will further help recovery of surface disturbances. When indoors looking from a window sill any liquid will do. What ever is at hand ( coffee, tea, dish soap, syrup ). Randall's leveled first surface mirror horizon is best for those going for the outdoor full round of stars on terrafirma. 

*Fogging of water artificial horizons can be reduced by removing the glass wind shield between observations.

Greg Rudzinski