The frisky dog bounding through the brush at left with ears flapping and tail flying is not just out for a romp. A superbly trained animal named Kansan, he is in the process of proving that he is the number one English springer spaniel in the nation. This is not an honor lightly won, as 41 top dogs discovered last week at the 16th English Springer Spaniel National Championships. The August A. Busch Memorial Wildlife Area at Weldon Spring, Mo., where the three-day trial was run in 70� temperatures, was heavily overgrown and dust-dry, making hunting tough and birds hard to scent. But to the fast-driving, black and white four-year-old owned by R. E. French, this mattered little. Kansan covered the difficult trial course like an eager vacuum cleaner, first flushing his birds for the hunter's gun, then retrieving them in record time. A springer spaniel's job is a complex one. Once he has flushed a bird, he is expected to wait motionless while it is shot. Then he is expected to mark its fall and retrieve it upon command. For a spaniel good enough to compete in championships, all this is second nature. But circumstances at the National, and at any major trial, are somewhat different from an autumn afternoon's hunt. A candidate for the top championship finds himself followed not only by his handler but by one or more official trial guns (who assure uniform shooting to all entrants), by the judges and by a gallery of enthusiastic but distracting spectators, talking, laughing, smoking, clicking their cameras and frequently pushing too close into the cover being hunted. Should a bird flush back across an end of the gallery instead of ahead of it, the dog may even be forced to run through the spectators to make his retrieve. Between the mingled scents of Old Spice, Old Briar and Old Forester, it is hardly surprising that an occasional spaniel goes astray. This was never the case with Kansan. In five tests on land and two in water, he consistently found the shortest distance between a downed bird and his handler, P. L. Scales. At the trial's end, there was little question in the minds of either judges or spectators that he was 1962's top springer.