Read "Secret of the River" by Fred M. White online for free on Textopian. Full text with search, annotations, highlights, and AI-powered reading aids.
"I don't quite get it," Blissett said.
"Simple enough," Nevil replied. "A strong coil of steel spring, long enough to cross the road, so that either end can be fastened to one of those stunted trees. If anybody happens to come along the road, then somebody who is in the plot releases the buckle and the whole thing goes back with a snap and shuts up in a space of about eight inches in diameter. If we carefully examine the stems of those trees, we shall see the marks made by the clips. Ah, here you are, it's quite plain."