Collis watched her for a while as her smile came and went, like the shadows on a summer afternoon. Her eyes closed, and as the train covered the remaining few miles into Panama City, she slept. Collis waited until she was breathing deeply, and then he went to the window and leaned out again, so that he could see the Pacific through the trees, and smell the damp cool mist that rose from the sea. He was quite sure now that Hannah had yellow fever; and worse than that, he was convinced that she was going to die.

The first he saw of Panama City was a blur of red rooftops through the flickering grey trunks of the palm trees. Then the train came out in the open, and he saw white crumbling buildings and brown cathedral spires, and a shallow bay of muddy turquoise in which steam tugs and sailing dinghies idly criss-crossed in each other’s wakes.

The city itself was built on a curved spit of land which hooked into the Pacific, crowded and chaotic and hazy. Behind the city, in the grey sea, Collis could make out the misty shapes of several small forested islands, and the spare outline of a large steam vessel, the draught of which was obviously too deep for it to approach the shoreline. Up above, the sky was heaped with cumulus clouds, but they seemed to be rolling sedately north-west, back towards the mountains.

Within a few minutes, the train was joggling and rattling over switches and junctions and slowing down into the railroad depot. It whistled once, but it was a despondent whistle, without an echo. The afternoon was too dull and flat for the sound to carry. The brake shoes squealed like dismally-slaughtered piglets, and the trans-Panama railroad train came to a queasy, shuddering halt.

Collis opened the compartment door. Hannah was still sleeping, although she had mumbled something, and turned over on the banquette. Beside the train, three nuns were waiting, with white-winged coifs, attended by a Jamaican porter and a wheeled basket chair. Collis stepped down from the train and hailed them, and the nuns rustled towards him, starched and pale, their rosaries swinging at their waists.

Unaccountably, Collis felt embarrassed. The nuns were so young and waxen-faced, and the porter so black and emotionless, and they had actually hurried to help a complete stranger who was sick of the yellow fever. When he thought how heroic he had felt at Culebra, offering to stay with Hannah, he felt ashamed.

The depot was a large, arched building, with murky skylights and flaking white-painted walls. It was in a constant hubbub, but in a minor key; a depressing sound of escaping steam, arguing porters, angry passengers, and clamouring children. Over the noise, Collis said, ‘She’s in there. I believe she has the yellow fever. La fièvre jaune.’