Meet the men even duller than a trainspotter, a roundabout enthusiast and a traffic cone collector. Leland Carlson, assistant vice-president of the Dull Men's Club, believes he has found a collection of British men who out-dull even the pin-ups who made the official Dull Men 2015 calendar.Among their number are a golf ball collector, a rail timetable compiler and a man who has kept a diary of every time he has mowed the lawn since 1980.The gentlemen and their eccentric and tedious interests are celebrated in a new book, Dull Men of Great Britain, a follow-up to the calendar released last year.John Potter, 60, from Northamptonshire, has spent the past 16 years putting together the European rail timetable.He was delighted to find that he had made it into the collection."I didn't make the 2015 Dull Men calendar. I wasn't dull enough, apparently," he said.Of his unusual job, Potter said: "I don't find it dull. A lot of people do though. It's all numbers."I think it's just public perceptions that anyone interested in railways is someone stuck at the end of the platform in an anorak, but that's a tiny fraction of what's involved in running the railways."David Grisenthwaite, from Kirkcaldy, Fife, said his wife was "bemused" by his keeping a record of every time he mows the lawn.Grisenthwaite, 87, said: "All I do is I keep a record every time I cut the grass, or the lawn if you want to put it grandly. I have done it since 1980 and I keep it meticulously. Obsessive I suppose is the word."The Dull Men's Club is billed as a place where "dull men - and women who appreciate dull men - share thoughts and experiences about ordinary things".Among their number are a handful of devoted collectors, including Martyn Vallance, from Cornwall, who has amassed more than 70000 golf balls, and James Brown, from Derbyshire, who owns 300 vacuum cleaners.Dr Mark Coulson, a psychologist from Middlesex University, wrote the foreword to the book: "The last 40 years has taught us that people derive happiness from lots of different things. It's about finding what works for you and I think these men have found that," he said. ..