“But of course I know; how else would I have agreed to await your coming?” the boy retorted, the scorn in his voice perfectly modulated to place us a step below him. He spat a shell on the ground by way of punctuation.

Holmes lowered his hand, his head tipped to one side as he, too, re-evaluated the urchin. “Are we to take delivery of the donkey and cart from you, Young Prince?”

The boy slid down from the wall and sauntered around towards the pens. “Not the same animal you had agreed upon, oah no,” he answered, the last two words an English interjection before returning to the vernacular. “That creature was good only for feeding the vultures, and moreover had the trick of breaking its hobbles on the first or second night out and trotting home to its stable. I succeeded in loosing its rope during the night and exchanging it for its sister, who is an ‘altogether more satisfactory beast.’ ” Again, the final phrase was in ornately accented English, which might have been disquieting except that I had the clear idea that it was merely his way of demonstrating what a man of the world he was.

We followed our unlikely guide past some stinking pens that were full to bursting with horseflesh, to one that was deserted but for one lone donkey, dozing in a corner. The boy climbed up on the gate and gave a little chirrup sound with his teeth, and the creature’s ears flapped, its head coming up and all four feet planting themselves on the ground. It then hesitated, seeing three of us, before sidling around to greet the boy, who reached out and scratched its skull; even in the dim light, I clearly saw the cloud of scurf and dust the motion raised. However, I could also see that the animal appeared well fed and alert.

“And the cart?” Holmes asked.

The boy swung his legs over the gate and dropped into the pen, splashing through the half-liquid and entirely noxious ground to the far corner of the pen, where he stuck his toes into invisible niches and clambered over the wall like a monkey. A minute later he reappeared around the outside of the pen, heaving at a miniature cart that contained a child-sized armload of hay. He stopped in front of us, let the traces drop, and gestured proudly at the light little vehicle. It had probably started life as a cart for the entertainment of small English children, and although its paint was long gone and the high sides had seen rough use, the solid craftsmanship held, and the repairs to its two big wheels and leather straps were neat. The boy stood looking up at Holmes, taking no notice of the muck to his knees; I wondered again about his mental acuity.

Holmes surveyed the object solemnly, and nodded.