“What of this ‘Cooee!’ then?”

“Well, obviously it could not have been meant for the son. The son, as far as he knew, was in Bristol. It was mere chance that he was within earshot. The ‘Cooee!’ was meant to attract the attention of whoever it was that he had the appointment with. But ‘Cooee’ is a distinctly Australian cry, and one which is used between Australians. There is a strong presumption that the person whom McCarthy expected to meet him at Boscombe Pool was someone who had been in Australia.”

“What of the rat, then?”

Sherlock Holmes took a folded paper from his pocket and flattened it out on the table. “This is a map of the Colony of Victoria,” he said. “I wired to Bristol for it last night.” He put his hand over part of the map. “What do you read?”

“ARAT,” I read.

“And now?” He raised his hand.

“BALLARAT. “

“Quite so. That was the word the man uttered, and of which his son only caught the last two syllables. He was trying to utter the name of his murderer. So and so, of Ballarat.”

“It is wonderful!” I exclaimed.

“It is obvious. And now, you see, I had narrowed the field down considerably. The possession of a gray garment was a third point point which, granting the son’s statement to be correct, was a certainty. We have come now out of mere vagueness to the definite conception of an Australian from Ballarat with a gray cloak.”

“Certainly. “

“And one who was at home in the district, for the pool can only be approached by the farm or by the estate, where strangers could hardly wander.”

“Quite so.”

“Then comes our expedition of to-day. By an examination of the ground I gained the trifling details which I gave to that imbecile Lestrade, as to the personality of the criminal.”

“But how did you gain them?”

“You know my method. It is founded upon the observation of trifles.”

“His height I know that you might roughly judge from the length of his stride. His boots, too, might be told from their traces.”

“Yes, they were peculiar boots.”

“But his lameness?”

“The impression of his right foot was always less distinct than his left. He put less weight upon it. Why? Because he limped — he was lame.”

“But his left-handedness.”

“You were yourself struck by the nature of the injury as recorded by the surgeon at-the inquest. The blow was struck from immediately behind, and yet was upon the left side. Now, how can that be unless it were by a left-handed man? He had stood behind that tree during the interview between the father and son. He had even smoked there. I found the ash of a cigar, which my special knowledge of tobacco ashes enables me to pronounce as an Indian cigar. I have, as you know, devoted some attention to this, and written a little monograph on the ashes of 140 different varieties of pipe, cigar, and cigarette tobacco. Having found the ash, I then looked round and discovered the stump among the moss where he had tossed it. It was an Indian cigar, of the variety which are rolled in Rotterdam.”

In Milan he had been advised to go to the Hotel Britannia, because it was not expensive, and English people went there. So he took a carriage, drove round the green space in front of Milan station, and away into the town. The streets were busy, but only half–heartedly so.

It must be confessed that every new move he made was rather an effort. Even he himself wondered why he was struggling with foreign porters and foreign cabmen, being talked at and not understanding a word. But there he was. So he went on with it.

The hotel was small and congenial. The hotel porter answered in English. Aaron was given a little room with a tiny balcony, looking on to a quiet street. So, he had a home of his own once more. He washed, and then counted his money. Thirty–seven pounds he had: and no more. He stood on the balcony and looked at the people going by below. Life seems to be moving so quick, when one looks down on it from above.

Across the road was a large stone house with its green shutters all closed. But from the flagpole under the eaves, over the central window of the uppermost floor—the house was four storeys high—waved the Italian flag in the melancholy damp air. Aaron looked at it—the red, white and green tricolour, with the white cross of Savoy in the centre. It hung damp and still. And there seemed a curious vacancy in the city—something empty and depressing in the great human centre. Not that there was really a lack of people. But the spirit of the town seemed depressed and empty. It was a national holiday. The Italian flag was hanging from almost every housefront.

It was about three o’clock in the afternoon. Aaron sat in the restaurant of the hotel drinking tea, for he was rather tired, and looking through the thin curtains at the little square outside, where people passed: little groups of dark, aimless–seeming men, a little bit poorer looking—perhaps rather shorter in stature—but very much like the people in any other town. Yet the feeling of the city was so different from that of London. There seemed a curious emptiness. The rain had ceased, but the pavements were still wet. There was a tension.

Suddenly there was a noise of two shots, fired in rapid succession. Aaron turned startled to look into the quiet piazza. And to his amazement, the pavements were empty, not a soul was in sight. Two minutes before the place was busy with passers–by, and a newspaper man selling the Corriere, and little carriages rattling through. Now, as if by magic, nobody, nothing. It was as if they had all melted into thin air.

The waiter, too, was peeping behind the curtain. A carriage came trotting into the square—an odd man took his way alone—the traffic began to stir once more, and people reappeared as suddenly as they had disappeared. Then the waiter ran hastily and furtively out and craned his neck, peering round the square. He spoke with two youths—rather loutish youths. Then he returned to his duty in the hotel restaurant.

“What was it? What were the shots?” Aaron asked him.