The effects of various head-gears on horses.

The functions of the most common head-gears for horses are analysed from a biomechanical point of view. With the exception of the stable halter are al l of them designed to enlarge the tensile forces transmitted through the re ins or the longe, and to concentrate the enlarged forces on sensitive parts of the horse's head: the nose, or the lips, mandible and tongue. Since the direction, duration and size of these tensile forces are the essential fac tors to modulate signals for controling the horse, a device has been develo ped to measure, or at least roughly quantify these forces. The mechanical c haracteristics of bosal, cavecon, serreta, kappzaum and hackamore are demon strated and compared with those of the two major types of bits: those with and without levers.