The following day we came to Aden and the mouth of the Red Sea, where the ship would pause for a few hours to take on coal. This would be our last land until Bombay, and Holmes and I were among the few walking wounded of the night before who waited to go ashore. The hills around the town seemed covered with tiny windmills, spinning in the hot wind, and the instant the ship dropped anchor, the sea around us filled with small canoe-type boats paddled by young boys, calling for the passengers to drop coins for them to dive after. From where I stood at the rail, the water looked so murky, thanks to the steamer’s huge screws, that I couldn’t imagine the boys seeing anything smaller than a gold guinea flashing past, but clearly the exercise was worth their while, or they wouldn’t have risked the sharks.

Heat settled over us as the launch approached the town, making me glad for once of the topee’s shade. We passed through the canoes and the dhows to tie up at the pier and be ceremoniously handed off; the solid ground felt oddly unforgiving beneath my feet, which in the eight days since leaving Marseilles had grown accustomed to the rise and fall of the decking. The air smelt intense, marvellously complex with the odours of dust and spice and animals, and only occasional whiffs of burnt fuel.

Our first stop was the post office, where we retrieved a handful of letters, including one from Mrs Hudson and two from my solicitors in London. A quick glance through them showed that there was nothing of any great urgency, although I did send off a telegram to the legal people to say that I’d got their letters and would write at leisure. We then slid the post into our pockets and turned into the bazaar.

Aden rides the border between several worlds, all of them represented in her marketplace. Skin tones from ebony to ivory, a thousand shapes of head covering, dialects to keep a linguist in ecstasy for a lifetime. Three dusty Bedu slipped down the streets behind a pair of British soldiers; a dark-skinned Jew displayed his copper pots to an African Moslem headed home from Mecca; four British tars with their distinctive rolling gait haggled with a Christian shopkeeper over the price of a small carpet; a pair of Parsee women, wrapped in loveliness and followed by a pair of watchful men, fingered lengths of brilliant silk; a British captain strolled with his lady, his eyes on her and not the pick-pocket trailing close behind.

All that in the first fifty feet, before Holmes ducked inside a gap between shops. However, I was ready for it, and made haste to follow him.