“The greatest and perhaps the wealthiest. I am aware, Mr. Holmes, that you take a very high line in professional matters, and that you are prepared to work for the work’s sake. I may tell you, however, that his Grace has already intimated that a check for five thousand pounds will be handed over to the person who can tell him where his son is, and another thousand to him who can name the man or men who have taken him.”

“It is a princely offer,” said Holmes. “Watson, I think that we shall accompany Dr. Huxtable back to the north of England. And now, Dr. Huxtable, when you have consumed that milk, you will kindly tell me what has happened, when it happened, how it happened, and, finally, what Dr. Thorneycroft Huxtable, of the Priory School, near Mackleton, has to do with the matter, and why he comes three days after an event - the state of your chin gives the date - to ask for my humble services.”

Our visitor had consumed his milk and biscuits. The light had come back to his eyes and the colour to his cheeks, as he set himself with great vigour and lucidity to explain the situation.

“I must inform you, gentlemen, that the Priory is a preparatory school, of which I am the founder and principal. Huxtable’s Sidelights on Horace may possibly recall my name to your memories. The Priory is, without exception, the best and most select preparatory school in England. Lord Leverstoke, the Earl of Blackwater, Sir Cathcart Soames - they all have intrusted their sons to me. But I felt that my school had reached its zenith when, three weeks ago, the Duke of Holdernesse sent Mr. James Wilder, his secretary, with the intimation that young Lord Saltire, ten years old, his only son and heir, was about to be committed to my charge. Little did I think that this would be the prelude to the most crushing misfortune of my life.

“On May 1st the boy arrived, that being the beginning of the summer term. He was a charming youth, and he soon fell into our ways. I may tell you - I trust that I am not indiscreet, but half-confidences are absurd in such a case - that he was not entirely happy at home. It is an open secret that the Duke’s married life had not been a peaceful one, and the matter had ended in a separation by mutual consent, the Duchess taking up her residence in the south of France. This had occurred very shortly before, and the boy’s sympathies are known to have been strongly with his mother. He moped after her departure from Holdernesse Hall, and it was for this reason that the Duke desired to send him to my establishment. In a fortnight the boy was quite at home with us and was apparently absolutely happy.

“He was last seen on the night of May 13th - that is, the night of last Monday. His room was on the second floor and was approached through another larger room, in which two boys were sleeping. These boys saw and heard nothing, so that it is certain that young Saltire did not pass out that way. His window was open, and there is a stout ivy plant leading to the ground. We could trace no footmarks below, but it is sure that this is the only possible exit.

“His absence was discovered at seven o’clock on Tuesday morning. His bed had been slept in. He had dressed himself fully, before going off, in his usual school suit of black Eton jacket and dark gray trousers. There were no signs that anyone had entered the room, and it is quite certain that anything in the nature of cries or a struggle would have been heard, since Caunter, the elder boy in the inner room, is a very light sleeper.