Picture a lucid, witty, warm and at times crotchety old man nearing his hundredth birthday; mix with a young, energetic traveling salesman; throw in a pair of teen-age daughters, a wife pursuing a mid-life career and place them in America's picturesque Pacific Northwest. Next, require that the salesman spend two years covering at least four thousand miles a month eking out a living selling dairy equipment directly to farmers. PRESTO! You have the...