The only other charm our secret club afforded was the wearing of a mysterious club pin. It was a silver beetle, with the letter G engraved on the head and the letter B on the body, while down the center of the back was the letter I (see Fig. 187). In public we called ourselves the G. I. B.'s, but it was only the initiated members who knew that these letters were to be read backward, and, with the beetle on which they were engraved, signified the "Big Bugs." Of course, we had some secret signs and signals, a secret hand grasp, a peculiar whistle as a warning to run, another meaning "lie still," and a third signifying "all is well."
[Illustration: Fig. 188 The Notched Washers.]
[Illustration: Fig. 189. Washers Fastened on Spools.]
[Illustration: Fig. 190. The Combination Lock.]
We found it necessary to close the entrance of our cave with a door fastened with a padlock, so as to keep meddlers out. The entire school had watched us build the cave house, and, of course, knew just where our entrance lay. Then, in addition to the outer door, we put in another one, half-way down the dark passageway. On this Bill rigged up a simple combination lock which would baffle any one who managed to pick the padlock. This inner door opened outward. It was hinged to the floor of the passageway, and swung up against a frame set in the passageway. At the top was a board whose lower edge lay flush with the edge of the door when it was closed. For the combination lock we used a couple of spools, each with one head cut off and the central hole plugged up with a stick of wood. In the floor and the top board of the frame, holes were drilled just large enough for the shanks of the spools to fit snugly in them. Next we made a trip to a hardware store for a file and a couple of large copper washers, about 1-1/4 inches in diameter. The washers were fastened to the inner ends of the spools after they had been pushed through the hole. The washer on the door came just to the edge of the door, while the other extended below the door frame and lapped under the door washer. Then in the edge of the washer on the frame a notch was filed, while in the other washer two notches were filed, so as to leave a tooth which fitted snugly into the notch of the first washer (see Figs. 188, 189). The door was locked by turning both the washers until the notch and tooth came in line with each other, then pushing the tooth through the notch, and turning the washers so that the frame washer hooked over the door washer. Then the door could be opened only when the tooth and notch were brought in line.