Russell is a big dog in a small body. If you compare his origin with the origin of today's Fox Terriers, Jack turns out to be closer to their age-old ancestors created for hunting and working in the hole, which had an iron will and need persistent training.
It gave the qualities of today's Jacks, their mind, attitude, physique, fantastic character, incomparable athleticism and agility. All this makes him a great house pet and companion.
He is always alert and ready for the next adventure or discovery. He looks at you with inquisitive clever eyes as he asks, "What is my master wants?" He loves his master and by all his behavior he is trying to show it. Loves to kiss, sit on their hands, loves caress and tenderness. He is capable to make rapid decision, self-confident, never timid, shy or hesitant. Here's a mix of the most diverse and sometimes incompatible qualities.
"Flying Dog" is one of the epithets that the nation awarded to Jacks. Why is "flying"?
Look at him, he's never all four paws on the ground, he always jumps, literally soars above the ground, as aerialist, in some fascinating dance. He is rarely nervous or aggressive, almost always friendly and active. He is small, dressed in white coat with a small red or black spots.
Dog recommends brushing the teeth, but not necessarily, talk about this later. They as well as people, constantly eat, between teeth also get stuck particles of food. In addition, very often dogs pick up on the street various garbage. Some dogs don't properly care the teeth become sick.