[1] It was characterized by widespread observation of previously unnoticed windshield holes, pits and dings, leading residents to believe that a common causative agent was at work.
It was originally thought to be the work of vandals, but the rate of pitting was so great that residents began to attribute it to everything from sand flea eggs to nuclear bomb testing.
Several hypotheses for the widespread damage were postulated: By April 15, close to 3,000 windshields had been reported as affected, which prompted mayor Allan Pomeroy to ask for help from Washington Governor Arthur B. Langlie and President Dwight D.
[3] The following week, hundreds of windshield pitting incidents were also reported in British Columbia, Alberta, and Ontario.
[4][5] The "Seattle Windshield Pitting Epidemic" as it is called has become a textbook case of collective delusion (not "mass hysteria" as reported).