QUOTES BY E. F. SEIDLER:
On Introducing the Horse to the Double-Bridle

"With the double bridle, we follow the same sequence of exercises, from the very beginning through the perfection of dressage, as with the snaffle, although in a shorter time span. At first walk, trot, straight and without head position. Only when the horse goes confidently into the bit on straight lines, we collect more, demand a head position. Flex the horse, go onto the circle, work in shoulder-in, travers, renvers, canter, and narrower turns. It would be detrimental for the horse's entire training, if the rider immediately wanted to ride everything he used to ride in a snaffle as soon as the horse has been introduced to the curb. For a few days he would go out of habit, but then he would become disobedient and withdraw behind the reins. The first task is to quietly get the horse used to the new bit. We must not start any lateral movements before the horse trustingly approaches the bit on a straight line. Otherwise we would give him a hint how to coil up behind the reins. Forward is the first demand made of a soldier's and utility horse. In the previous work with the snaffle we could convince ourselves that he is capable of performing lateral movements. If they should require further improvement, it cannot be addressed until we have the horse on the bit." (1837; translation: T. Ritter)