And now the curate's thoughts wandered back to the mystery of the bishop's purse. Who could have taken it? There were two women in the railway carriage and two musicians. Horatio much preferred crimes with a woman at the bottom and he disliked musicians, so he decided that one of these fair travelers—of course, they were fair—had turned the trick. He loved the crisp vulgarity of that expression—turned the trick. And, forthwith, he loosed his fancy over the paths of fearless adventure that he loved to tread. Now he was a great detective, on the track of a desperate criminal, and his gentle soul thrilled in the conflict of plot and counter-plot. In all literature and theology there was nothing that stirred Horatio Merle like these imaginings.
Half an hour later, Harriet, listening at the study door, heard a faint scratching sound and smiled in satisfaction.
"He's writing," she said to herself and stole swiftly away. She had an errand in the village and could leave now with a clear conscience.
The scratching sound continued. It came, however, not from the writing table, but from the window casement, which presently swung open, apparently of its own accord. Whereupon Horatio came back, with a start, from his heroic wanderings, back to the world of drab reality and looked blinkingly about him. There, on the window ledge, sharply silhouetted against the wistaria leaves, stood Martin Luther. His tail swayed swiftly from side to side like the ebony baton of a chef d'orchestre. His staring eyes were like two circular holes through which you saw the green of the leafy background. He held his head proudly, he was carrying something. Horatio shut his eyes quickly. There were moments when he hated Martin Luther.
When he looked again the cat was standing by his chair purring noisily to attract attention to something that lay on the floor. It was a field mouse, just such a one as he had watched in the cornfield the day before and had scolded Martin Luther for frightening. Perhaps it was the same field mouse.
"You little murderer!" cried Merle. "It would serve you right if I had left you to drown in the canal!"
He pushed the cat away roughly and picked up the unconscious little creature. The field mouse stirred in his hand. Merle examined it tenderly and was surprised to find it apparently quite uninjured. He stroked it gently with his finger. Suddenly the mouse sat up and began preening itself with an incredibly rapid whirring movement of its tiny hands. Then just as suddenly the movements stopped, the little head drooped, and the eyes closed.
"Poor little thing!" said Horatio. "The shock was too much for it."
He had scarcely uttered these words when the mouse opened its eyes again and went on preening itself as if nothing had happened.
"You're sleepy, that's what's the matter with you," decided Merle, after watching several repetitions of this performance. "I'm going to take you home and put you to bed. As for you, Martin Luther," he turned severely to the cat, "you are a disgrace to the family and deserve to be excommunicated."