The earlier twentieth century was, of course, overshadowed by two World Wars, during both of which the work of the cathedral became increasingly important and provided much-needed support to a mainly Christian public. Despite losing some lay clerks to the forces, the choir continued to sing for services, and its work was particularly important during the Great War of 1914-18. Music was well-chosen, with innovations such as the introduction of plainsong, and services heartened those who attended, providing comfort during a time of great anxiety and the loss of men serving in the trenches. With orchestras silenced, and before the arrival of broadcasts and recordings, concerts were also welcomed, and the cathedral was filled to capacity. Between the wars there were new ventures: a carol service, early attempts at outreach education for schoolchildren, a rebuilt organ and improved schooling of the choristers. The Second World War brought different challenges, particularly the need for precautions against air raids. The evening nave Evensong was affected by the blackout rules, and vulnerable stonework, glass, books, and valuables needed to be moved to safety where possible. Happily, though, the city escaped the worst bombing.