“If you’ll tell me what you have done since you left the Crossing, it might help to solve the puzzle,” Foster replied.

Lawrence made a gesture of resignation.  “I suppose it must be told.  I went to California and didn’t get as well as I expected.  There was a good deal of sea-fog on the coast and after a time I went farther south.  That’s one reason I didn’t write; I felt languid and dejected and didn’t want to alarm my folks.  Well, I tried Mexico and got rather worse; besides I found lounging tiresome work.  In consequence, I joined a steamer going north and her doctor told me that dry cold mountain air was the best cure for troubles like mine.  I met Walters on the voyage up the coast.”

“Perhaps you had better describe him,” Lucy suggested.

“Walters looks about my age and is thin and dark; an amusing fellow and remarkably well informed.  In fact, I couldn’t guess his nationality; he seemed to have been everywhere.  He had good manners, but somehow one missed——­”

“Something that good manners must be founded on,” Lucy interposed.

Foster saw that they had argued about the man before, because Lawrence smiled indulgently.

“Then how did he make your acquaintance?” he asked the girl.

“That was not altogether Lawrence’s fault.  Walters was cleverer than he thought.”

“And he mailed one of the letters that did not arrive?”

“The fellow,” Lawrence continued, “was a pleasant companion and when I mentioned why I was traveling agreed that the mountains were best for me.  Told me about some friends of his whom the air had cured.”

“In short, he recommended your trying Banff,” Lucy remarked.

“He did me a good turn there.  We separated at Seattle, but I found him at Victoria, where I stopped some weeks.  It was there I met Lucy, who was going to Banff.  I must explain that she’s a mountaineer.”

The girl blushed.  “I climbed in the Olympians twice with college friends.  They talked about exploring some of the northern glaciers next summer, and as we wanted a change, I persuaded mother to spend a month or two at a mountain resort where I could get some practice on the ice.”  She paused and added in a grave voice:  “I really don’t climb well, Mr. Foster, and doubt if I shall venture on the rocks again.”

“Well,” resumed Lawrence, “we decided to go to Banff together.  I got better rapidly and we made a few easy excursions into the mountains, but the weather was bad and we didn’t like our hotel.  Then Walters turned up again and told us about this place.  In fact, he was rather enthusiastic about it and said we’d find good rock climbs at the door, so we agreed to move.”

“And took Walters?”

“He was an amusing fellow.  He’d a way of finding something interesting for one to do and was always ready when he was wanted; a very useful man to have about.”

Foster imagined his comrade might have found the fellow about when he was not wanted, but Mrs. Stephen’s smile was illuminating.  It seemed to hint that Lawrence had found Walters useful because he took her off his hands.  Foster thought it curious that the man was satisfied with his part, since Lucy was a very attractive girl.  Walters had obviously not attached himself to the party on her account.