Many animals can hear through the ground. Elephants, it has been said, can listen through their feet. But seismic vibrations have long been out of reach for the common human.
Until now! For the Shoe Horn Foot-Mounted Stethoscope has arrived. Idle, the Shoe Horn (or Shoe Horns) appear to be nothing more than fashionable toe-mounted trumpets. But when the need arises, or the mood strikes you, nonchalantly tilt a boot forwards and begin the subterranean sonic experience. Sound is carried through a flexible tube (optionally concealed within a trouser leg) all the way up to your earpiece.
Possible benefits of always having your Shoe Horn at the ready include: early warning of approaching tube trains; earthquake detection; cracking floor-mounted safes; locating rodents, elephants or sexually available frogs; surreptitious eavesdropping; impromptu doctoring of fainted peoples without the indignity of kneeling down.
Dual Shoe Horns can be used for a stereo effect. Note that the Shoe Horn is of no assistance if you experience difficulty donning footwear.