John Russell's first dog, "Trump," was bought for looks alone.
Tied to a milkman, and bought on a whim while out walking, "Jack" Russell had no way of knowing if this dog could actually hunt.
The only picture of Trump that exists was drawn more than 50 years after the dog had died. The art (if it can be called that) was commissioned by the Prince of Wales (King George VII) who came to consider the Reverend Russell a friend.
The "14-inches tall" description of Trump that is commonly cited comes from a description of the painting, but in fact there is nothing in the painting that gives any indication of the dog's real height in life.
The putative 14-inch height appears to be a wild guess based on the shoulder height of an adult fox. A fox and a dog are built very differently, however, and a 14-inch tall dog would have chest at least two or three inches larger than a similarly-sized fox.
Going on the size of working dogs in the UK today, a more likely guess is that Trump was somewhere between 12 and 13 inches tall.
In The Real Jack Russell Terrier (1993), Eddie Chapman writes:
As a breeder of Jack Russells, I get a steady string of enquiries for working dogs, especially from hunt terrier men, and I can state categorically that if give the choice, ninety-nine percent of hunt terrier men would buy an under 12" worker, if it was available, over a 14" one.
For the last twenty years I have always has the policy of lending out any surplus working terriers I have to other hunts. The most I had out at any one time was the season 1986/87 when I had no less than twenty-six workers on loan to different hunts up and down the country. At the start of each season I regularly get requests from hunt terrier men for the loan of a worker or two and the same request is always made with the enquiry. 'Any chance of a good small one?' and very often it's only a small one they want.
These small Jack Russells are invaluable for hunt terrier work, and not only in the South, for all hunts gets their quota of Foxes that run into those tiny ungettable places where a really small terrier can make a difference between a quick dig and an all day effort to locate the vulpine."