He had changed some of the words and she had improved the melody.

The work on the accompaniment was progressing finely now, and Billy was so glad!--when she was absorbed in her music she forgot sometimes that she was ever so unfit an artist's sweetheart as to be--jealous of a portrait.
It was quite early in the month that the usually expected "January thaw" came, and it was on a comparatively mild Friday at this time that a matter of business took Billy into the neighborhood of Symphony Hall at about eleven o'clock in the morning.

Dismissing John and the car upon her arrival, she said that she would later walk to the home of a friend near by, where she would remain until it was time for the Symphony Concert.
This friend was a girl whom Billy had known at school.

She was studying now at the Conservatory of Music; and she had often urged Billy to come and have luncheon with her in her tiny apartment, which she shared with three other girls and a widowed aunt for housekeeper.

On this particular Friday it had occurred to Billy that, owing to her business appointment at eleven and the Symphony Concert at half-past two, the intervening time would give her just the opportunity she had been seeking to enable her to accept her friend's invitation.