Friar Bartolomeo turned to his desk again and shuffled the papers, looking for something. He handed Luna a book. ‘Take this. At least your visit will not have been in vain. I believe you will enjoy it, though the mathematics might be difficult for a girl.’

Luna took the book and frowned. She didn’t like to be criticised, but her expression turned to one of delight when she realised he’d given her the textbook every young student of astronomy began their studies with: the astronomer Sacrobosco’s Tractatus de Sphaera. ‘How did you know this was exactly the book I wanted? Thank you!’ She opened the thick cover and scanned the title page. It was a marvellously detailed wood cutting of the author and another man sitting beneath an astrolabe.

‘Take it home with you,’ Friar Bartolomeo said, and Luna realised he was hovering over her. She closed the book and tucked it under her arm.

‘Thank you so very much for this,’ she said again.

Friar Bartolomeo went to open the door. He muttered something that she did not hear but she watched him looking left and right.

‘Are you expecting someone?’

‘What? No, no.’ He seemed flustered, though he didn’t move from where he stood.

Perhaps, as she’d feared, his mind had begun to go soft. ‘Are you well?’

The look he gave her was one of surprise. Then he clasped his hands together and sighed heavily, and there was her friend once more, his eyes crinkling. ‘You are my kindest student, dear girl. I thank you for your concern.’

‘I don’t know what I’d do without your guidance. You cannot get sick, for I would be lost.’ She squeezed his shoulder gently.

‘Now, no fussing please.’ He patted her head as he ushered her through the door and Luna found herself unexpectedly dismissed.

After walking back across the piazza, her leg throbbed. She’d expected to be sitting down for the next hours, not walking again so soon, so she took some rest on one of the stone seats. The sun’s warmth encouraged her to linger. She was glad the sessions with the painter had finished but she had to admire his dedication to his craft. Even though she’d tried his patience with her reading and fidgeting, he’d stayed focused. Luna watched a country woman gathering her baskets and the remaining herbs she hadn’t sold that morning. Other traders were closing up their market stalls. A final few customers wandered amongst them. A gush of dirty water spread across the dry stone as a serving girl from the tavern emptied her cleaning bucket. The smell wafted all the way across to where Luna sat but it wasn’t enough to make her move. Rather, she let herself dwell on the drop of her shoulders and the heaviness in her chest.