"Perhaps Mr. Boyne is some person who has sought retirement in a similar manner," Marigold suggested.
"No. If I'm not mistaken, Mr. Boyne is playing a very deep and rather dangerous game--how dangerous I cannot yet discover."
"But you could discover nothing when you watched--just as I failed to find out any fact," she said. "I had no idea you were on the watch."
"I saw you on Tuesday night," he laughed. "You arrived at the house about half-past eight, and had a great trouble getting in."
"Were you there?" she cried eagerly. "I never dreamed that you were in the vicinity. Yes, you are right. I rang and banged on the door half a dozen times before I could attract auntie's attention. She generally leaves the door unlocked in case anyone should call."
"Boyne returned about twenty minutes after you had left, but though I watched till midnight, he did not come out again."
"Couldn't you take a day off one day and follow him when he goes out in the morning?" the girl suggested. "I would do it, but I fear that he'd recognise me."
"I might. But I think I may be more successful at night. It is very difficult to keep observation upon a person in broad daylight. In the darkness it is much easier."
"Why not try again to-night?" suggested Marigold. "I'll go with you."
"Sunday night is a bad night. We know his habits on week-days, but he may have gone out all day to-day," he replied. "No; to-morrow would be more likely."
"Then let's both go there to-morrow night, and if he comes out of the house we'll watch where he goes."
With this suggestion Gerald agreed, and after she had smoked the cigarette he handed to her from his case, they resumed their punting up-stream in the afternoon sunshine.
Next night they met by appointment at Hammersmith Broadway station at half-past eight, and after a consultation, it was arranged that Marigold should call on her aunt on some pretext, and having ascertained if Boyne had returned, she would rejoin Gerald at a spot in King Street.
Hence he lounged about the busy thoroughfare for a quarter of an hour until she returned with the news that Boyne had been home since six o'clock, he having returned unusually early.
"Ah! That's a good sign," said Gerald. "He'll certainly go out again to-night!"