Edward L. Anderson, Riding and Driving
“ If the bit stands stiffly, the chain is too tight. If the branches of the curb-bit come back in a line with the reins or anywhere near it, the chain is too loose. The chain will be found to be of the right length when, maintaining its place in the chin groove, a slight tension upon the reins gives such a pressure upon the jaw of the horse. If the curb-chain be not brought from one hook to the other on the outside of the snaffle, it will interfere with the action of both bits and will pinch the lips of the horse. ”
