AVE6328765: 1920s: Women working on railroad loading train car, push cart on tracks / Bridgeman Images

AVE6328774: United States, 1960s: close up of head lamp / Bridgeman Images

AVE6328804: 1920s: Two women stand side by side / Bridgeman Images

AVE6328807: United States, 1940s: Animated circles on red background / Bridgeman Images

AVE6328810: 1920s: Child in costume stands on top of hot-air balloon, waving / Bridgeman Images

AVE6328340: Russia, 1950s: man controls machine on mountain / Bridgeman Images

AVE6328343: Russia, 1950s: steam and smoke around machine / Bridgeman Images

AVE6328349: 1980s: Students walk in protest / Bridgeman Images

AVE6328361: 1980s: Model aircraft / Bridgeman Images

AVE6328376: 1980s: Astronauts in space suits ride elevator up to enter rocket / Bridgeman Images

AVE6328379: 1980s: Man in suit sits in chair talking / Bridgeman Images

AVE6328388: Russia, 1950s: lady carries churn of milk / Bridgeman Images

AVE6328406: Russia, 1950s: boy rides tractor / Bridgeman Images

AVE6328454: United States, 1960s: police officer drives at night / Bridgeman Images

AVE6328466: United States, 1960s: police officer talks to men after presentation in classroom / Bridgeman Images

AVE6328514: United States, 1960s: woman holds baby in ambulance / Bridgeman Images

AVE6328544: United States, 1960s: Montage of different wall clocks / Bridgeman Images

AVE6328580: United States, 1960s: Hand puts bread in toaster / Bridgeman Images

AVE6328583: United States, 1960s: Toaster with toast, hand puts bread in toaster / Bridgeman Images

AVE6328619: United States, 1960s: Woman scrubs floor with brush / Bridgeman Images

AVE6328628: United States, 1960s: Meat cooking in electric skillet / Bridgeman Images

AVE6326492: 1970s: A boy talks to a mailman on his route / Bridgeman Images

AVE6326495: United States, 1960s: boy with parcel walks towards building / Bridgeman Images

AVE6326498: 1970s: Stylized animation of dog chasing a mailman / Bridgeman Images

AVE6326782: United States, 1960s: Worker taking one of many printing plates and mounts it for printing onto paper. / Bridgeman Images

AVE6328936: United States, 1970s: car lights in rain at night / Bridgeman Images

AVE6328942: United States, 1970s: side view as man drives car at night / Bridgeman Images

AVE6328951: United States, 1970s: Clouds over planet Earth / Bridgeman Images

AVE6328957: United States, 1930s-1940s: A helmsman turns a helm to steer a ship / Bridgeman Images

AVE6328963: United States, 1930s-1940s: A plant worker inspects the displays on a steam powered electricity generator / Bridgeman Images

AVE6328975: United States, 1930s-1940s: A close-up of the opening of a smoke stack / Bridgeman Images

AVE6329017: United States, 1960s: Hand sharpens knife on grinder / Bridgeman Images

AVE6329032: United States, 1960s: Medium shot of golfer / Bridgeman Images

AVE6329038: United States, 1930s-1940s: Close up of a tapped furnace pouring molten metal into a large, open container / Bridgeman Images

AVE6329074: United States, 1930s-1940s: A factory worker manufactures a car part using a manually operated machine / Bridgeman Images

AVE6329077: United States, 1930s-1940s: Car parts move along a hanging track in a Henry factory / Bridgeman Images