"If I can have the coöperation of you girls," said Miss Romaine, with her grave smile, "I think I can manage everything satisfactorily. We will be partners in a kindly conspiracy that will do no harm to any one and may do some one a great deal of good."
The girls agreed eagerly, glad to have mercy upon Kate and Lottie if by so doing they could benefit the poor girl whose odd association with Kate Speed was now made clear to them.
But there were still the mysterious robberies at the school to be explained. The morale of the students was seriously affected by the repeated alarms. They were nervous and jumpy, predicting direful mishaps in the near future, and several went over to the side of the timid girl who wanted to go home.
Miss Romaine, desperate at the inertia of the local police, was talking of hiring city detectives.
Things were at this pass when Nan met Frank Gibbs one day and the young fellow asked her to make up a party for one last outing on the lake. The boys had already met Miss Romaine, and she rather encouraged the friendship between them and the three girl chums.
"Isn't it pretty cold?" protested Nan, who, with the other girls, had resorted to sweaters and sport coats. "We are apt to freeze to death."
"Not if we make the kind of fire I'm thinking about," the boy retorted, with a grin. "Come on, be a good sport. We'll roast potatoes and have a real party."
When Nan passed the invitation on to Sadie and Jo they assented more readily than she had expected.
"We need something to take our minds off robbers and mysteries and things," Sadie added. "I've reached the point where every little shadow holds a villain all its own."
"And I've found out I have nerves," Jo added gloomily. "That's an entirely new discovery for me. Sure! Let's go and roast potatoes. It will do us good."