function make_nav_box(a){nav_box_start();make_opt("Introduction",".",a);make_opt("Day 1","day1.html",a);make_opt("Day 2","day2.html",a);make_opt("Day 3","../../endurance/running/boston2008.html",a);make_opt("Day 4/5","day4-5.html",a);make_opt("Day 6","day6.html",a);make_opt("Day 7","day7.html",a);make_opt("Day 8","day8.html",a);make_opt("Day 9","day9.html",a);nav_box_end()};