“Bitzer,” said Thomas Gradgrind. “Your definition of a horse.”

“Quadruped. Graminivorous. Forty teeth; namely, twenty-four grinders, four eye-teeth, and twelve incisive. Sheds coat in the Spring; in marshy countries, sheds hoofs, too. Hoofs hard, but requiring to be shod with iron. Age known by marks in mouth.” Thus (and much more) Bitzer.