The Old English bulldog was a breed

Dog breed

Dog breeds are groups of closely related and visibly similar domestic dogs, which are all of the subspecies Canis lupus familiaris, having characteristic traits that are selected and maintained by humans, bred from a known foundation stock....

 of dog

Dog

The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...

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The Old English bulldog was compact, broad and muscular, as reflected in the well-known depiction Crib and Rosa

Crib and Rosa

Crib and Rosa is an 1817 painting by Samuel Raven, a follower of Abraham Cooper; Christie's attributes the painting to the latter, noting a variant held by the American Kennel Club....

. The average height was approximately 15 inches, and they weighed about 45 pounds. A particular characteristic of the breed was the lower jaw that projected considerably in front of the upper jaw, which made possible a strong, vice-like grip.