train whistle in the rain

From Alice B. Johnson’s “Where Children Live” (my great-grandmother’s book of poetry)

Why must I sleep so lightly when the rain
Beats dismally against my window pane,
Through dark and endless hours of the night
That fill themselves with loneliness and fright?
Why must I lay awake and sometimes hear,
Not only rain — but suddenly and clear,
The whistle of a speeding troop-filled train?
Such lonely sounds at night —
Train whistle —
Rain.