Frank, the "passengers will please refrain" reference is probably to a humoresque song which sometimes syrfaces at railroading special events, usually in the darker corners. As The Black Diamond String Band (Michigan) used to sing it:

PASSENGERS WILL PLEASE REFRAIN
(ANON)

Passengers will please refrain,
From flushing toilets while the train
Is in the station, darling, I love you;
We encourage constipation,
While the train is in the station,
Moonlight always makes me think of you.

If you wish to pass some water,
Simply call the pullman porter,
He'll place a vessel in the vestibule;
If the porter isn't near,
Try the platform in the rear,
The one in front is likely to be cool.

If the women's room be taken,
Never be the least forsaken,
Never show a sign of sad defeat;
Try the men's room 'cross the hall,
And if some man has had the call
He'll courteously relinquish you his seat.

If these efforts prove in vain,
Simply break a window pane;
This novel method used by very few;
And as we go strolling through the park,
Goosing statues in the dark,
If Sherman's horse can take it,why can't you?

Well, now you know!