Mr. Sabin took up the card and studied it.

“Lord Robert Foulkes.”

“Do I know this gentleman, Duson?” Mr. Sabin asked.

“Not to my knowledge, sir,” the man answered.

“You must show him in,” Mr. Sabin said, with a sigh.  “In this country one must never be rude to a lord.”

Duson obeyed.  Lord Robert Foulkes was a small young man, very carefully groomed, nondescript in appearance.  He smiled pleasantly at Mr. Sabin and drew off his gloves.

“How do you do, Mr. Sabin?” he said.  “Don’t remember me, I daresay.  Met you once or twice last time you were in London.  I wish I could say that I was glad to see you here again.”

Mr. Sabin’s forehead lost its wrinkle.  He knew where he was now.

“Sit down, Lord Robert,” he begged.  “I do not remember you, it is true, but I am getting an old man.  My memory sometimes plays me strange tricks.”

The young man looked at Mr. Sabin and laughed softly.  Indeed, Mr. Sabin had very little the appearance of an old man.  He was leaning with both hands clasped upon his stick, his face alert, his eyes bright and searching.

“You carry your years well, Mr. Sabin.  Yet while we are on the subject, do you know that London is the unhealthiest city in the world?”

“I am always remarkably well here,” Mr. Sabin said drily.

“London has changed since your last visit,” Lord Robert said, with a gentle smile.  “Believe me if I say—­as your sincere well-wisher —­that there is something in the air at present positively unwholesome to you.  I am not sure that unwholesome is not too weak a word.”

“Is this official?” Mr. Sabin asked quietly.

The young man fingered the gold chain which disappeared in his trousers pocket.

“Need I introduce myself?” he asked.

“Quite unnecessary,” Mr. Sabin assured him.  “Permit me to reflect for a few minutes.  Your visit comes upon me as a surprise.  Will you smoke?  There are cigarettes at your elbow.”

“I am entirely at your service,” Lord Robert answered.  “Thanks, I will try one of your cigarettes.  You were always famous for your tobacco.”

There was a short silence.  Mr. Sabin had seldom found it more difficult to see the way before him.

“I imagined,” he said at last, “from several little incidents which occurred previous to my leaving New York that my presence here was regarded as superfluous.  Do you know, I believe that I could convince you to the contrary.”

Lord Robert raised his eyebrows.

“Mr. dear Mr. Sabin,” he said, “pray reflect.  I am a messenger.  No more!  A hired commissionaire!”

Mr. Sabin bowed.

“You are an ambassador!” he said.

The young man shook his head.

“You magnify my position,” he declared.  “My errand is done when I remind you that it is many years since you visited Paris, that Vienna is as fascinating a city as ever, and Pesth a few hours journey beyond.  But London—­no, London is not possible for you.  After the seventh day from this London would be worse than impossible.”