Archimedes came to us with fluorescent overhead lighting. The fixtures are about 12 inches long and built into recesses in the ceiling. Each fixture holds one ten watt tube. Sadly, they don’t produce much light. In fact, a previous owner went so far as to line the insides of the recesses with aluminum foil in the hope that would reflect a bit more light. I don’t think that was terribly effective. The tubes just don’t put out much light.
We have seven of these fixtures. Four in the main salon, one in the aft stateroom, and one in each head.