In 1932, we estimated that fatalities from automobile accidents increased by 24 percent in just a year. Between 1929 and 1931, the number of Americans killed by cars exceeded the number killed in the trenches during World War I. To help readers stay safe, we explored some of the different factors in accidents. In most cases, the drivers, not the machines, were at fault. The three most common causes of accidents were as follows: driving off the roadway, exceeding the speed limit, and driving ahead without having the right of way. Driving on the wrong side of the road, skidding, signaling improperly, and runaway vehicles without drivers also made roads a more dangerous place for pedestrians. Weekends also made for reckless driving, as 20 percent of all automobile fatalities occurred on a Sunday. The next most dangerous day to drive was Saturday, and after that, Thursday.