The church service on that hot Sunday had been especially memorable, with two students from The Pierre Monteux School providing cello and violin duets that mesmerized the congregation, many of whom fanned themselves with hymnbooks or bulletins as their heads rhythmically swayed to the glorious music.

At another point in the service, the pianist played the introduction to the communion song, then began singing in Spanish to the wonderment of several rows of young campers who had been fidgeting before being brought to attention. “Tu has venido a la orilla, no has buscado, ni a ricos, ni a sabios.” The youngsters knew the hymn, “Pescador De Hombres,” and joined in the verses and refrain, nodding at each other and smiling.

The lilt of the tune was as gentle as rocking waves: “Lord, you have come to the seashore, neither searching for the rich nor the wise, desiring only that I should follow.” In Spanish, the words were caressing like a lullaby whispered to an infant.

Later came the rousing recessional by cellist and violinist. And later still, on the long ride home, came the unexpected sound of the trumpet. Long, drawn-out honks, followed by shorter sequences, then another two-minute blast.

Every time the steering column turned, the truck horn blared. Every time the horn blew, another motorist glared. Several cars braked, their drivers anticipating a parade perhaps, or mistaking our honking as some sort of warning. A rattled RV driver inched to the nearest turnoff, got out and checked to see if two bicycles were still attached to the rear rack. We honked on.

After rounding the corners of a country lane, we finally stopped the obnoxious vehicle only to discover the horn continued a life of its own, with or without ignition.

A look under the hood produced no clues, nor did the manual, which simply stated the obvious: The truck was equipped with a horn. There were no schematics, no instructions about disconnecting wires, no fuses to stop the beastly bugling.

Frazzled, we slammed down the hood and darted for home, trying to ignore the commotion we were causing along the highway as one after another motorist pulled over for a truck bellowing more loudly than the Egg Rock foghorn.

Mortified, we watched a station wagon topped with two kayaks edge itself onto a skimpy road shoulder so we in the big V-8 with the offensive big horn could pass, hiding our red faces as best we could behind the visors.

Even after we parked on the back road near the house – the woods, we hoped, might muffle the sounds – the erratic horn honked and honked, prompting a neighbor to wander over with his concerns.

Forty-five minutes later, when the cellist and violinist and the Spanish-singing campers were all a pleasant memory, silence returned after a long Sunday drive.

Finally, the mysterious fist-sized gadgets under the hood were yanked free of the wires leading to them. This time, the windshield wipers didn’t stop, nor did the blinker lights go on.

Captain Hornblower had figured it out.