He hooked the reins over an iron peg and let Thomas stroke the mare’s neck and then followed the doctor into the house.

The doctor was a youngish man, new to the district after the previous physician’s retirement, and he was already kneeling by Ellen’s side with his left hand against Mary’s forehead and the other fumbling to open a small black box.

‘Can I help you, sir?’ Harry put Thomas down.

‘No, thank you.’ The doctor removed his hand from Mary to open the box, which contained a glass thermometer wrapped in a piece of flannel that smelled strongly of antiseptic. ‘It’s rather precious. I wouldn’t like to drop it.’ He shook the instrument vigorously and asked Ellen to lift Mary’s dress, then placed the thermometer beneath the child’s armpit and waited.

‘Is that a thermometer, doctor?’ Harry asked. ‘I’ve never seen one so small.’

The doctor nodded, and after a few moments removed the instrument and looked at it steadily. ‘Medium fever,’ he murmured, and then sat back on his haunches. ‘Has she complained of a sore throat, or earache?’ he asked Ellen.

‘A sore throat, yes, but not earache.’ Ellen found she was trembling. ‘Though she was rubbing the back of her neck. And she didn’t want to eat or drink anything.’

The doctor looked down Mary’s throat. ‘She perhaps found it painful to swallow,’ he said. ‘Her throat is inflamed.’ He patted the little girl’s arm and looked up at Harry. ‘Yes, it is a thermometer. A much smaller and more convenient one than we’ve had previously.’ He wrapped the instrument in the piece of flannel and put it back in the box. ‘It tells me that your little girl does not have a high fever, so I don’t think she has measles, but if she comes out in spots’ – he turned to Ellen – ‘you must send for me immediately, and keep the other children away from her as it’s very contagious.’

He thought for a moment before going on, ‘At worst it might be quinsy. At best, tonsillitis. If she has difficulty swallowing, don’t worry about her not eating, but give her sips of cool boiled water. Just continue what you’ve been doing.’ He glanced at the bowl of water. ‘Bathe her to bring down her temperature, but don’t let her get cold either.’

‘Thank you, doctor,’ Ellen said tearfully. ‘We’re very grateful.’

He nodded. ‘Keep the other children away, if you can. One sick child is enough to deal with.’

When Harry had seen the doctor out, he turned to Ellen. ‘I’ll tek Sarah and Thomas to my ma and ask if she’ll look after them for a day or two, just until Mary’s got over ’fever.’