"I am afraid," he replied, "that we can't take any active measures. You have put us on our guard and we shall keep our eyes open. But I think that is all we can do, unless we hear something further."
"But," I exclaimed, "don't you think that it is a very suspicious affair?"
"I do," he replied. "A very fishy business indeed, and you were quite right to come and tell us about it."
"It seems a pity not to take some measures," I said. "While you are waiting to hear something further, they may give the poor wretch a fresh dose and kill him."
"In which case we should hear something further, unless some fool of a doctor were to give a death certificate."
"But that is very unsatisfactory. The man ought not to be allowed to die."
"I quite agree with you, sir. But we've no evidence that he is going to die. His friends sent for you, and you treated him skilfully and left him in a fair way to recovery. That's all that we really know about it. Yes, I know," the officer continued as I made signs of disagreement, "you think that a crime is possibly going to be committed and that we ought to prevent it. But you overrate our powers. We can only act on evidence that a crime has actually been committed or is actually being attempted. Now we have no such evidence. Look at your statement, and tell me what you can swear to."
"I think I could swear that Mr. Graves had taken a poisonous dose of morphine."
"And who gave him that poisonous dose?"
"I very strongly suspect—"