Occasionally, inexplicable fads break out, such as planking in 2011. In the 1920s, it was pole sitting — a test of endurance that saw people sitting on top of flag poles for extended periods. As these historical photos show, it wasn’t for the faint-hearted. Alvin “Shipwreck” Kelly is credited with starting the craze after sitting on a flagpole in 1924 for 13 hours and 13 minutes. Kelly began taking commissions to sit on poles, and was frequently photographed reading the newspaper or brushing his teeth while standing or sitting high up in the air. After other pole sitters took his record, Kelly sat on a flagpole for 49 days in Atlantic City in 1929. “Shipwreck” Kelly developed a system to allow him to sleep and not fall off. His Wikipedia entry explains that he would put his thumbs in holes in the pole shaft, so if he swayed the pain in his thumbs would force him upright without waking up.…