The Scottish Terrier originated in the highlands of Scotland and is believed to be Scotland's oldest breed of dog. They were farm dogs and were kept to rid the land of vermin. They were selected for their gameness and hunting ability. The Scotsman required his dogs to be fearless enough to go to ground to attach any prey; small enough to fight their way back out; and hardy enough to withstand a rough life and rigorous climate. These were the attributes deemed essential in the early hunting terriers and they are still the attributes we look for today.
Our breed standard states that the Scottish Terrier is a "small, compact, short-legged dog of good bone and substance. His head is long in proportion to his size. He has a hard, wiry, weather resistant coat and a thick-set cobby body which is hung between short, heavy legs. These characteristics, joined with his very special keen, piercing, 'varminty' expression, and his erect ears and tail are salient features of the breed. The Scottish Terrier's bold, confident, dignified aspect exemplities power in a small package."
"The Scottish Terrier should have a thick body and heavy bone. The principal objective must be symmetry and balance without exaggeration."
Generally, a well-balanced Scottish Terrier dog should weigh from 19 to 22 pounds and a bitch from 18 to 21 pounds.
Be sure and check out these sites for additional information on the breed:
Scottish Terrier Club of America
San Francisco Bay Scottish Terrier Club
Scottish Terrier Club of California
American Kennel Club