Rob led the way, and after him came the fat chum, with Merritt bringing up the rear. There was a method in this arrangement, for, while the pilot could test each girder, so as to pronounce it secure, the rear guard was able to keep an eye on luckless Tubby, and even give him an occasional word of advice.
Now that the morning had arrived they could see better with each passing minute; and Rob soon declared there was no necessity for any further delay.
It was always a principle with him to grapple with a difficulty, and carry out his plans, without letting anything like dismay seize hold of his heart.
Accordingly Rob now made a start.
"Why, this is dead easy," was the way he sung out, after he had passed along the swaying girder for a little distance. "All you have to make sure of is that your grip is sound. Then keep hunching along, foot by foot. And don't look down any more than you can help, because it might make you dizzy."
Tubby shut his teeth hard, and began to follow after the pilot. He made good progress until he had about reached the middle of the rocking span. Then Rob was really alarmed to hear a sudden loud cry, and feel his slender hold shaken violently.
Something had certainly happened to unfortunate Tubby!