Breed of dog developed in 19th-century England from the bulldog and the now-extinct white English terrier. The Spanish pointer was later bred into the line to increase its size. The bull terrier was developed as a courageous fighting dog but not an aggressive fight provoker, and it is generally friendly. A muscular dog, it is considered, for its weight, the strongest of all dogs. It has a short coat, tapering tail, erect ears, and deep-set eyes. It stands 19–22 in. (48–56 cm) high and weighs 50–60 lbs (23–27 kg). There are two varieties, coloured and white.