The note tells the truth.

It was written by a Frenchwoman who probably came from Ottawa.
She is in love with Storri, and jealous of Miss Harley, whom she thinks Storri aims to marry.

You said nothing about Storri seeing Miss Harley, but he does.

Miss Marklin was afraid to tell you and Miss Harley was afraid to write you that feature of the situation, fearing you would pitch in rough.

It shows they have sense." This was the first time Richard had heard how Storri enjoyed the privilege of Dorothy's society while he was warned from the door.