six o'clock
All afternoon , just before the night of the fancy dress ball , the four girls took turns watching at the front windows of the Preston house for the belated boys . In spite of Tom 's telegram , plainly stating the day of their arrival , the motor launch boys had not put in an appearance . Soon after luncheon David went down to the river bank to watch for them . At six o'clock he came back to say that he had waited as long as possible and had seen no sign of the `` Sea Gull . '' It looked as though the boys had been delayed . The girls were in despair . Here they had planned a wonderful surprise party for the boys , and their guests of honor were not going to be present .