Source Text:
The captain intended to say still more, but at that moment a sound like the vibrations of a long minor chord of a far-off orchestra of wind instruments resounded through the ship.

With an apology the captain rose to leave, explaining as he did so that he must be needed on very important business, since everybody knew that he was with his Right Reverence and would not venture to trouble the ears of his Right Reverence for anything trifling.

Dissect the Syntax
Sentence Structure Breakdown
 

Main idea: The captain is interrupted mid-speech by a musical signal heard throughout the ship.

Second idea: He apologizes and departs, explaining the interruption must be of serious importance.

Phrase-by-Phrase Paraphrase
 
“a sound like the vibrations of a long minor chord of a far-off orchestra of wind instruments”
A distant, melancholic musical tone resembling wind instruments reverberates through the ship
“resounded through the ship”
The sound carried across all areas of the vessel
“With an apology the captain rose to leave”
He excused himself courteously and got up to depart
“he must be needed on very important business”
The signal implied his immediate presence was required for something serious
“would not venture to trouble the ears of his Right Reverence for anything trifling”
No one would dare interrupt his time with Beelzebub unless the matter were truly significant
Semantic Summary
 

He is stating that:

The captain is suddenly summoned by a reverberating musical signal—its tonal description evoking both beauty and urgency. He apologizes to Beelzebub and leaves, suggesting that the matter must be important, as protocol forbids disturbing his audience with Beelzebub for anything trivial.

Why This Is So Strange (and Worthwhile)
 

  • He begins with a musical interruption — the sound itself is described with lyrical, almost sacred imagery, suggesting a harmonious but serious cosmic order.

  • Hierarchy and reverence are strictly upheld — even summoning a captain requires grave necessity when he is in the presence of a “Right Reverence.”

  • The narrative uses subtle theater — breaking the technical discussion with an almost liturgical moment, underscoring tone and theme.

Summary
Just as the captain was about to elaborate further, a distant, musical signal—likened to a minor chord from far-off wind instruments—echoes through the ship. Recognizing the sound as a summons, he excuses himself respectfully, affirming that it must be a matter of real significance; no one would dare interrupt while he was with Beelzebub unless it were urgent.