Mutagen vs Carcinogen Mutagen and carcinogen are two terms that have a lot in common. There is a potential that a single substance could be both of them at the same time and be only one of the two, as well.
A curb bit is a type of bit used for riding horses that uses lever action. It includes the pelham bit and the Weymouth curb along with the traditional curb bit used mainly by Western riders. Kimblewicks or Kimberwickes are modified curb bits, and a curb bit is used in a double bridle along with a bradoon.
The curb chain applies pressure to the curb groove under a horse's chin when the curb rein of the bit is used. When the curb rein is pulled, the shank of the bit rotates back towards the chest of the horse and the cheek (upper shank) of the bit rotates forward (since it is a lever arm).