Testing Gravity in carboy

Attached one end of rubber band to hydrometer and the other to a bamboo skewer. Sanitized the hydrometer. Attempted to take a measurement with this contraption. The skewer slipped and fell partially into the beer. The hydrometer was pushed into the beer by the rigid rubber band or if the rubber band were shaken to give slack, the hydrometer would be pulled down by the slack rubber band or even pushed up by the rigid band. No measurement could be made.