AS I look back through the years of my association with John Thorndyke, I am able to recall a wealth of adventures and strange experiences such as falls to the lot of very few men who pass their lives within hearing of Big Ben. Many of these experiences I have already placed on record; but it now occurs to me that I have hitherto left unrecorded one that is, perhaps, the most astonishing and incredible of the whole series; an adventure, too, that has for me the added interest that it inaugurated my permanent association with my learned and talented friend, and marked the close of a rather unhappy and unprosperous period of my life.Memory, retracing the journey through the passing years to the starting-point of those strange events, lands me in a shabby little ground-floor room in a house near the Walworth end of Lower Kennington Lane. A couple of framed diplomas on the wall, a card of Snellen's test-types and a stethoscope lying on the writing-table, proclaim it a doctor's consulting-room; and my own position in the round-backed chair at the said table, proclaims me the practitioner in charge.