I finally discovered the source of the slow leak in the bilge of the sailboat. Actually, Mario figured it out when I found water accumulating in the bow as I retrieved the 110 jib stored there. Mario observed that the Sailboat Shop, who installed the depth sounder, failed to apply adequate sealant to the through hull fitting, using only a mechanical connection. Mario found an underwater epoxy and sealed it both above and below the waterline. When we pulled the boat from the water it was a thick, solid looking seal. After Mario made this repair, I had a completely dry sailboat again for the rest of the week plus the boat was on the water.