Elizabeth Karr, The American Horsewoman
“ As she is riding a racking horse and seated on a two-pommeled saddle, she holds the reins firmly in her left hand and by a steady pull on them she balances herself and keeps her horse up to his gait. But this steady pull will soon ruin the tenderness and sensitiveness of any horse's mouth, and this is the reason why racking horses generally have very hard mouths, many of them requiring to be well held up or supported in their rack by the reins. As this pulling upon the reins also gives considerable support to the rider, many ladies prefer a racking horse. ”
