He raised his eyes languidly from the old black-letter volume which he had opened. “It is cocaine,” he said—“a seven-percent solution. Would you care to try it?”
“No, indeed,” I answered, brusquely. “My constitution has not got over the Afghan campaign yet. I cannot afford to throw any extra strain upon it.”
He smiled at my vehemence. “Perhaps you are right, Watson,” he said. “I suppose that its influence is physically a bad one. I find it, however, so transcendently stimulating and clarifying to the mind that its secondary action is a matter of small moment.”
“But consider!” I said, earnestly. “Count the cost! Your brain may, as you say, be roused and excited, but it is a pathological and morbid process, which involves increased tissue-change and may at last leave a permanent weakness. You know, too, what a black reaction comes upon you. Surely the game is hardly worth the candle. Why should you, for a mere passing pleasure, risk the loss of those great powers with which you have been endowed? Remember that I speak not only as one comrade to another, but as a medical man to one for whose constitution he is to some extent answerable.”
He did not seem offended. On the contrary, he put his fingertips together and leaned his elbows on the arms of his chair, like one who has a relish for conversation.
“My mind,” he said, “rebels at stagnation. Give me problems, give me work, give me the most abstruse cryptogram or the most intricate analysis, and I am in my own proper atmosphere. I can dispense then with artificial stimulants. But I abhor the dull routine of existence. I crave for mental exaltation. That is why I have chosen my own particular profession—or rather created it, for I am the only one in the world.”
“The only unofficial detective?” I said, raising my eyebrows.