Harriet had been playing tricks on them.

She wondered where Harriet was.

Jane would have given the signal, but dared not do so.

In the first place she was not sure that she could imitate a crow so as to deceive a person, and in the second place the boys were too close to her to run any chances.
"They are here, all right, boys," cried George.

"I was certain of it all the time." "It may be spooks," answered Larry Goheen.
"Well, just let them come out.