Crime scene: 162 mystery solving puzzles to find out who the murderer is

Chapter 122 Gunshots from the Deck
The "Intrepid" small motorboat swayed in the middle of the storm, bumping forward.As the storm subsided, a gunshot sounded from deck one.The criminologist Professor Fordney dropped the detective novel that he had not been able to read, and rushed up the escalator in a few strides.At the bend at the end of the escalator he saw Stuart Myerson leaning over the body of the instant kill.

At this moment, the dome of the sky burst open, lightning flashed with thunder, as if the sky was grinning like a ghoul.The deceased had gunpowder burns on his head.Captain Larsen and the criminologist immediately launched an investigation to ascertain the location of every passenger on board at the time of the incident.The investigation began with the passengers closest to where the body was found.

The first to be questioned was Nathan Cohen, who said he was in the cabin finishing a letter when he heard the gunshots.

"May I have a look?" asked the captain.

Fordney looked over the captain's shoulder and saw the small, legible print all over the boat's letterhead.Apparently the letter was addressed to a lady.

The passenger in the next cabin was Miss Magnet Mills Wayne.She replied that, frightened by the great storm, she had taken refuge in the cabin of her fiancé James Montgomery opposite, about a quarter of an hour before the shooting.The latter corroborated her statement, explaining that they had not rushed down the aisle out of fear that their reputations might be damaged if they appeared together so late.Fordney noticed a dark red stain on Montgomery's pajamas.Miss Millsway appeared emotional and nervous when asked what she was doing at the time of the incident.After investigation, the location of the remaining passengers and crew is unassailable.

Excuse me, who is the captain's suspicion?Why?
[Answer] Nathan Cohen, because on such a bumpy boat, how could it be possible to write such neat words?

(End of this chapter)