Country Life, 1937, illus Anne Bullen
Reprinted and extended 1946 as The Young Horsebreakers
Janet and her cousin Felicity learned to ride in Eastbourne, and they think there’s not a lot more they need to learn about riding. Then they go to stay with Aunt Rose on Exmoor, and there are two Exmoors, Brownie and Mayfly, for them to ride on a nearby farm. It does not go well, and the girls realise how little they know. Then Uncle Tom comes to stay, and he helps the girls school the half-broken ponies.